showed a dramatic increase in SFP from the first two rounds to the final two rounds of the ..... A 2 (Gender) Ã 2 (Group) Ã 5 (SOA) Ã 2 (Response) ANOVA was.
Keynote Speakers and Lecturers Journal of Sport & Exercise Psychology, 2008, 30(Suppl.), S1-S5 © 2008 Human Kinetics, Inc.
Early Career Distinguished Scholar Lectures, 2008 Skilled performance: From action to perception to understanding Sian L. Beilock, University of Chicago What makes a skilled performer different from his or her novice counterpart? At first glance, one might suggest that the answer is simple. It is the quality of overt behavior that separates exceptional performers from those less skilled. We can all point to many real-world examples of such performance differences—just try comparing any professional athlete with his or her recreational counterpart. Although actual performance is one component that differentiates skilled individuals from novices, my research program suggests that these overt performance distinctions are only part of the picture. In this talk I will present a series of studies exploring differences in the attentional substrates and memory structures governing novice and skilled performance as they unfold in real time, as well as the implications that motor experience carries for the representation and understanding of skill-relevant information— even in situations where there is no intention to act. Specifically, I will show that activities as diverse as language comprehension, memory judgments, and preferences for objects/ events in one’s environment are modulated by one’s motor skill expertise. Together, this work highlights differences in the cognitive and neural operations supporting novice and skilled performance on the playing field and beyond. Implications for learning, training, and performance breakdowns under stress will be discussed. Intention–behavior discordance: Personality, social cognitive, and environmental explanations in the physical activity domain Ryan E. Rhodes, University of Victoria Most of the population have positive intentions to engage in physical activity (PA) but fail to act. Therefore, the need to understand action control (i.e., translating an intention into behavior) is warranted in order to focus intervention efforts. In this presentation, I concentrate on the evidence for two proposed mechanisms of intention–behavior discordance: (1) the possibility of incidental PA and the insufficiency of intention as a mediator of PA antecedents and (2) likely moderators of the intention–PA behavior relationship. Several data sets of adult populations collected from my laboratory over the last 6 years are used to evaluate these possible mechanisms. An extended theory of planned behavior framework is used to integrate the findings, but several proximal (intention strength, initiation automaticity, decisiveness, self-regulation processes), central (affective attitude, perceived control, social commitment, sedentary behavior identification), and distal (perceived environment, personality) constructs are evaluated as antecedents of action control. The results suggest that intention, as currently measured, is a necessary but potentially insufficient antecedent for understanding physical activity. Proximal, central, and distal antecedents contribute to intention–behavior discordance in PA. Understanding profiles of intention–behavior relationships by past behavioral experience may be helpful in focusing targeted interventions. Reconceptualization of the intention construct and interactive models of person–environment–behavior relations are also explored. S1
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Early Career Distinguished Scholar Lecture, 2007 Visual information: When we use it influences how we use it Matthew Heath, University of Western Ontario An issue of continued debate in the visuomotor neurosciences concerns the nature of the visual information serving motor output. On the one hand, Goodale and Milner’s (1992: Trends Neurosci) influential perception/action model asserts that visually guided actions are served via dedicated visuomotor networks of the dorsal visual pathway. Notably, this visual pathway is thought to process absolute (i.e., Euclidean) visual information in a strict egocentric frame of visual reference. On the other hand, converging work from my laboratory as well as others’ has shown this assumption not to be so straightforward; that is, reaching and grasping can be supported by interacting egocentric and allocentric (i.e., scene-based) frames of visual reference (e.g., Heath et al., 2006: Exp Brain Res). In my talk, I will provide a theoretical basis for understanding when and why multiple frames of visual reference influence motor output. First, I will outline the important control differences surrounding visually and memory-guided reaching movements (e.g., Heath, 2005: Motor Control) and demonstrate that the aforementioned actions are differentially reliant on central planning versus response-produced feedback mechanisms. Second, I will extend the just-mentioned findings to work involving pictorial illusions and show that the degree to which actions are specified by central planning versus online control mechanisms impacts whether unitary or multiple reference frames serve motor output (e.g., Heath et al., 2006: Exp Brain Res). Last, I will highlight work showing that specific awareness of the need to correct an ongoing reaching trajectory influences the nature of the visual information supporting visually guided action (e.g., Krigolson & Heath, 2006: Exp Brain Res).
Senior Lecturers Motor Development Two limbs, four limbs and a brain: Lessons learned across the lifespan Jill Whitall, University of Maryland Understanding how our limbs are coordinated and controlled together has been a career-long quest. Initially I was interested in how interlimb coordination develops in infant walking and other locomotor skills. In this endeavor I was heavily influenced by the dynamic systems perspective on motor development. Subsequently, I investigated four limb and finger coordination in adults, in typically developing children, and in children with developmental coordination disorder. More recently I have been interested in how to restore upper extremity limb coordination and control in older individuals who have suffered a stroke. Across this body of work, the role of the brain has become increasingly salient to me. Indeed, noninvasive methods of measuring brain activation and excitability have provided clues to brain–behavior relationships. In this lecture, I will highlight a few key studies and describe the lessons I have learned along the way. By lessons I mean not only my understanding of the development and recovery of limb coordination across the lifespan but also my self-discovery of factors that have influenced the direction and insights for my own academic lifespan.
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Motor Learning and Control Neural plasticity and stroke recovery: Motor learning applications James H. Cauraugh, University of Florida Since the 1996 seminal papers by Nudo and colleagues, stroke research on the functional and structural plasticity in the cerebral cortex of adult mammals has proliferated. Even though the evidence favoring movement-dependent recovery is sound, 65% of stroke survivors continue to struggle with motor dysfunctions. During the past 8 years, we investigated neural plasticity and chronic motor dysfunctions while manipulating motor learning and control variables. Indeed, a unique set of studies evolved: (a) active neuromuscular stimulation on the impaired arm, (b) coupled bilateral movement training (i.e., active stimulation on the impaired arm and simultaneous movements in the unimpaired arm), (c) blocked and random practice schedules, (d) long-term movement training, and (e) increased mass on the unimpaired arm. Summarizing these studies and conducting a meta-analysis determines progress toward improving stroke motor recovery.
Sport and Exercise Psychology Why the study of motivation (in the physical domain) is still so motivating Joan L. Duda, University of Birmingham Pulling from research conducted in sport, physical education, and exercise-related activities, the aim of this presentation is to provide some observations regarding the study of motivation in these settings. Specifically, I will argue for (1) the importance of distinguishing between the quantity and quality of motivation, (2) the motivational significance of perceptions of competence and how that competence is construed, (3) going beyond variations in perceived competence in understanding motivation-related patterns, (4) the implications that motivational differences hold for health, (5) the need to integrate across theories of motivation, and (6) the relevance of motivational theories to the development and testing of interventions in the physical domain. It will be suggested that although progress has been made regarding this important and complicated topic, work in the area of motivation continues to provide intrigue and challenge!
Keynote Speaker, Human Kinetics Lecture Feeling the beat: The origins of music in rhythmic movement Laurel J. Trainor, McMaster University Music is perceived largely in the auditory modality. However, it is well known that rhythmic music makes us want to move in time to the beat, and it appears that music and dance evolved together. In this talk I will explore the idea that music evolved in part from rhythmic movement. The ability to make rhythmic movements is evolutionarily older than the ability to hear rhythm, and common neural mechanisms can be seen in some primitive species for the movements involved in communicative sound production and for the perception of
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those sounds. In humans, we have shown that there are bidirectional connections between auditory and movement systems by demonstrating that how we move affects how we interpret an auditory rhythm pattern. We played an ambiguous, repeating six-beat rhythm pattern for infants, while we bounced half of them on every second beat (as in a march) and half on every third beat (as in a waltz). Following this familiarization, infants who were bounced on every second beat chose as familiar (listened longer to) an auditory version of the rhythm pattern with accents on every second beat whereas those bounced on every third beat chose as familiar an auditory version with accents on every third beat. Similar results were obtained when infants were blindfolded, indicating that visual input is not necessary. We have also shown that movement influences how adults perceive rhythm. Furthermore, in adults, we have shown that galvanic stimulation of the vestibular nerve alone can bias the interpretation of an ambiguous auditory rhythm. This is particularly interesting because the vestibular system develops early in both ontogeny and phylogeny, suggesting that it might play a primal role in the development of human rhythm perception. Finally, we have found that enriched early experience linking rhythm and movement, as in kindermusik classes for infants, appears to speed the development of the Western bias for preferring rhythms based on groups of two over rhythms based on groups of three.
Keynote Speaker, Motor Development Getting a grip on handedness: The origin problem Brian Hopkins, Lancaster University The origin and change problems go to the heart of attempts to understand ontogenetic development. As for handedness, many studies have been published about the changes it undergoes during early and later childhood. The same cannot be said for how a hand preference originates. Nevertheless, there are a number of testable models that address the origin problem with regard to handedness. One will be emphasized because its core feature is the claim that physical activity of the mother during the last trimester of pregnancy can exert a lateralizing influence on the fetal brain, and thereby on prenatal asymmetries in posture and movement. These motor asymmetries are then assumed to exert a bias on the postnatal acquisition of a hand preference. Evidence in support of the model is considered with the aid of data from studies concerned with the prenatal and early postnatal development of posture and movement.
Keynote Speaker, Motor Learning and Control Object representations used in action: A gripping and moving story of control and manipulation Randy Flanagan, Queen’s University, Kingston The remarkable manipulative skills of the human hand are neither the result of rapid sensorimotor processes nor of fast or powerful effector mechanisms. Rather, the secret lies in the
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way manual tasks are organized and controlled by the nervous system. Successful manipulation requires the selection of motor commands tailored to the task at hand and the relevant physical properties of the manipulated objects. Because of long time delays associated with sensorimotor loops, feedback control cannot support the swift and skilled coordination of fingertip forces observed in most manipulation tasks. Instead, the brain relies on feedforward control mechanisms that take advantage of the stable and predictable physical properties of these objects. In this talk, I will provide evidence that the brain learns and makes use of internal models of object dynamics (in addition to limb dynamics) both to estimate the motor commands required to achieve desired sensory outputs and to predict the sensory consequences of motor commands. I will also discuss experiments examining the coordinate frame(s) in which the dynamics of familiar and novel objects are represented. Finally, I will describe results from recent experiments suggesting that predictions about object weight, used when lifting, result from the interaction between two sources of knowledge: slowly adapting statistical knowledge about the relationship between size and weight for families of objects and rapidly adapting knowledge about the weights of specific objects.
Keynote Speaker, Sport and Exercise Psychology Role of affective attitudes in determining health behaviors Mark Conner, University of Leeds Social cognition models such as the theory of planned behavior (TPB) are used to explain, predict, and change health behaviors, including physical activity and exercise. This presentation overviews the use of such models and examines recent extensions to such work, particularly drawing on our work at Leeds. Two main areas will be considered in relation to such models: intention stability as a moderator and affective attitudes as an additional variable. Work on moderators in models such as the TPB has focused on the intention–behavior relationship. Temporal stability of intentions has emerged as a key moderator of this relationship, with more stable intentions being better predictors of behavior. Primary studies and meta-analyses demonstrating this effect will presented along with evidence that intention stability can mediate the effects of other moderators. Work on additional variables within models such as the TPB has identified a number of variables that add to their predictive power. Affective attitudes emerge as one key additional variable. Recent revisions of the TPB (i.e., the twofactor TPB) have acknowledged the important role that affective attitudes might play. The current presentation draws on distinctions between anticipatory/hedonic and anticipated/ self-conscious affect to explore the importance of these two types of affect in determining various health behaviors. Data from meta-analytic and primary research studies will be used to demonstrate the power of anticipatory/hedonic affect over and above cognitive factors in predicting health behaviors within the context of traditional social cognition models. Similar data are presented in relation to anticipated/self-conscious affect. In addition, examples of how anticipatory/hedonic affect and anticipated/self-conscious affect can be manipulated and the impact on health behavior change will be presented. These findings highlight the importance of intention stability and affective attitudes as determinants of health behaviors and suggest useful directions for research in this area.
Symposia Journal of Sport & Exercise Psychology, 2008, 30(Suppl.), S1-S27 © 2008 Human Kinetics, Inc.
Preconference Symposium Title: Five Decades of Impact in Sport and Exercise Psychology: A Legacy of Mentorship McCullagh, Penny, California State University–East Bay; Bob Christina, University of North Carolina; Dan Gould, Michigan State University; Larry Brawley, University of Saskatchewan; Deborah Feltz, Michigan State University; Brad Hatfield, University of Maryland; Deb Crews, Arizona State University; Jenny Etnier, University of North Carolina Greensboro; and Shawn Arent, Rudgers University Daniel M. Landers completed his Ph.D. at the University of Illinois in 1968 under the mentorship of Gunther Lueschen. He then moved on to teach at SUNY Brockport where he mentored numerous undergraduate students, getting them involved in research. From there, he went on to the University of Washington, Pennsylvania State University, and finally Arizona State University, from where he will retire in June of 2008. He has mentored over 50 master’s students and 20 doctoral students. In this seminar, some of his former students will share their ideas and reflections about their careers and research as it grew from their interactions with him.
Motor Learning and Control Title: Transcranial magnetic stimulation in motor control and learning research. Organizer: Tim Welsh, University of Calgary Transcranial magnetic stimulation in motor control and learning research: Introduction Welsh, Timothy N.; University of Calgary Transcranial magnetic stimulation (TMS) is a noninvasive neuroscientific technique that is growing in popularity as method for gaining insight into the role of different cortical areas in cognitive and motor processes. This symposium has been organized to provide an overview of the technical and methodological aspects of TMS research in the area of motor control and learning. The symposium will open with a review of the mechanisms and uses of TMS (Welsh). This introductory information will be followed a series of specific talks aimed at providing reviews of different lines of TMS-based research. These topics include: online vs. offline learning (Robertson), smooth pursuit eye movements (van Donkelaar), action observation (Théoret), and movement disorders (Chen). Transcranial magnetic stimulation: Mechanisms, uses, and limitations Welsh, Timothy N.; University of Calgary
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In transcranial magnetic stimulation (TMS), a transient magnetic field generated outside the skull is used to induce a brief electric current in the electroconductive extra- and intracellular medium inside of the skull. The induced electric currents subsequently activate action potentials in local neurons. Because of the architecture of the cerebral cortex and the depth and orientation of the induced electric currents, cortical interneurons are activated to a much greater degree than projection neurons. The relatively selective activation of cortical interneurons has important implications for the manner in which TMS can be used to study the neurological basis of human behavior. The introductory talk of this symposium will review these important technical and anatomical issues before addressing the main uses and limitations of TMS in the study of motor control and learning. Using TMS to determine the organization of motor skill consolidation Robertson, Edwin M.; Harvard Medical School and Beth Israel Deaconess Medical Center Our first floundering attempts at a sport are transformed into the smooth, graceful, and powerful performance of an athlete through practice. Long after practice, our motor skills continue to be processed “off-line” during consolidation. The brain areas critical to motor consolidation are poorly understood. The same brain areas may support consolidation over wake and sleep, indicating a time, rather than brain-state dependent organization. Alternatively, off-line processing may have a brain-state dependent organization, with different brain areas supporting consolidation over wake and sleep. One brain area associated with the processing of motor skills is the primary motor cortex. Here we used transcranial magnetic stimulation to determine the functional contribution of the primary motor cortex to motor consolidation over wake and sleep. Disruption of the primary motor cortex with repetitive transcranial magnetic stimulation blocked the development of off-line improvements over wake. In contrast, disrupting the primary motor cortex did not block the development of off-line improvements over sleep. Thus, the primary motor cortex makes a critical contribution to motor skill consolidation over wake but not over sleep. This provides insight into the organization of off-line processing by showing that distinct mechanisms may support consolidation over wake and sleep. The contribution of the human FEF and SEF to smooth pursuit initiation Van Donkelaar, Paul; University of Oregon Smooth pursuit eye movements function to keep moving targets foveated. Behavioral studies have shown that pursuit is particularly effective for predictable target motion. There is evidence that both the frontal and supplementary eye fields (FEF and SEF, also known as the dorsomedial frontal cortex) contribute to pursuit control. The goal of the current experiment was to determine whether these two areas made different contributions to the initiation of pursuit in response to predictable compared to unpredictable target motion. Transcranial magnetic stimulation (TMS) was used to temporarily disrupt each area around the time of target motion onset. TMS over the FEF delayed contraversive pursuit markedly more than ipsiversive pursuit and this direction-dependent difference was more deeply modulated during pursuit of unpredictable than predictable target motion. By contrast, TMS over the SEF resulted in a much more muted modulation of pursuit latency that was similar across both predictable and unpredictable conditions. Taken together, we conclude that the human
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FEF, but not the SEF, makes a significant contribution to the processing required during the preparation of contraversive pursuit responses to unpredictable target motion and this contribution is less vital during pursuit to predictable target motion. Shared representations of action in human primary motor cortex Théoret, Hugo; Université de Montréal It has been suggested that a direct-matching mechanism operates in the human brain in much the same way to what has been described in monkeys with mirror neurons. Evidence for the existence of a human mirror neuron system (hMNS) comes in part from transcranial magnetic stimulation (TMS) studies where an increase in the amplitude TMS-induced motor evoked potentials (MEPs) during action observation is thought to reflect modulation of the MNS. Here, we describe a series of studies that aim at better understanding the properties of this direct-matching mechanism and investigate its possible role in specific pathological conditions. First, we will describe the basic design that is used to probe MN function in human primary motor cortex. Then, we will show that even in the absence of conscious awareness, a symbolic value can be ascribed to an otherwise neutral stimulus and modulate motor cortical outputs revealing the influence of top-down inputs on the MNS. Finally, we will address the controversial claim that a MNS dysfunction underlies specific aspects of autism spectrum disorder symptomatology and present preliminary data suggesting a role for abnormal shared motor representations in psychopathy. Magnetic stimulation studies in movement disorders Chen, Robert; University of Toronto and Toronto Western Research Institute Transcranial magnetic stimulation (TMS) is a noninvasive way to study and modulate brain excitability and plasticity. TMS studies demonstrated that cortical activation and deactivation associated with voluntary movement is slower in Parkinson’s disease (PD) and this may be a correlate of bradykinesia. Several different cortical inhibitory circuits can be tested by paired TMS. They can be used to investigate the pathophysiology of PD and the effects of treatment. Short-interval intracortical inhibition (SICI) is normalized by deep brain stimulation (DBS) of the subthalamic nucleus, whereas DBS of the internal globus pallidus normalize a different type of inhibition, the silent period. Reduction short latency afferent inhibition (SAI) may reflect side effects of dopaminergic medications, and reduced long latency afferent inhibition (LAI) may reflect nondopaminergic features of PD. Both SAI and LAI are improved by STN DBS. PD patients also demonstrate deficient long-term potentiation (LTP) like plasticity, especially in those with levodopa-induced dyskinesia. Presynaptic inhibition is also deficient in PD. Abnormal cortical and spinal inhibition was also demonstrated in patients with psychogenic dystonia, suggesting these changes may be a consequence of abnormal movement or an endophenotypic trait. High-frequency repetitive TMS (rTMS) is a potential treatment for PD motor symptoms and low-frequency rTMS might be a potential treatment for levodopa-induced dyskinesia.
Title: On the origins of 1/f noise in human motor behavior. Organizer: Didier Delignieres, University of Sport Sciences-Montpellier On the origins of 1/f noise in human motor behavior: Introduction
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Delignieres, Didier; University of Sport Sciences, Montpellier; Kjerstin Torre, University Montpellier I; Christopher T. Kello, Georges Mason University; David L. Gilden, University of Texas at Austin 1/f fluctuations have been discovered in a number of time series collected in psychological and behavioral experiments (e.g., Beltz & Kello, 2006, Gilden, 2001; Torre, Lemoine & Delignières, 2007). This ubiquity is per se an intriguing phenomenon, and the origin of such fluctuations remains in question. One considers that this very specific kind of fluctuation plays an essential role in the stability of behavior, and in the adaptability and flexibility of organisms. A number of hypotheses have been proposed for accounting for this phenomenon. Currently, two categories of explanations can be discerned: A first category of hypotheses seeks a general explanation for the existence of 1/f noise. For example, Kello, Beltz, Van Orden, and Turvey (2007) consider 1/f fluctuations as the natural outcome of self-organization processes in complex systems. Cognitive functions are conceived as metastable patterns of neural and behavioral activity, and this metastability generates intrinsic fluctuations that universally exhibit the 1/f fluctuations. According to this point of view, 1/f noise is supposed to manifest in all aspects of behavior, so long as the same behavior is repeated consistently with minimal perturbation (Beltz & Kello, 2006). A second line of reasoning seeks domainspecific explanations. 1/f noise is supposed to emerge from specific underlying processes within the system, and consequently local models could be proposed that take into account the serial properties of behavior, and their alteration under various experimental conditions (Delignières, Torre & Lemoine, in press, West & Scaffeta, 2003). This symposium will confront proponents of the two hypotheses, and will oppose epistemological approaches, modeling perspectives and experimental strategies. The link between coordination and pervasive 1/f scaling Kello, Christopher T.; Georges Mason University It is readily apparent that physical activities are acts of coordination among bodily components and, by extension, component neural systems involved in the control of bodily movements. Sometimes coordination is simple in its regularity of movement as in the phase locking of musical activities set to a metronome. But more often, coordination is complex and irregular, as in a runner’s gait over uneven terrain or an assisted play in basketball. These “rough and ready” coordinations appear to be as robust as they are ubiquitous: Neural and bodily components organize themselves temporarily to suit current intentions and conditions, but may quickly reorganize as intentions and conditions change. In this communication, I propose that such coordinations have a common dynamical basis derived from three distinct but related bodies of work. Most directly related to physical activity, von Holst (1939) proposed relative coordination as a functional basis of movement coordination in biological models. Its functionality stems from a balance between independence versus interdependence among component activities, e.g., fin and leg oscillations, respectively. More generally, Ising (1925) proposed a model of ferromagnetism that has since been broadened to study how patterns organize and reorganize among many kinds of system components, e.g., electron spins. Recently, Kelso (1995) proposed metastability as a key property of human neural and behavioral systems that requires a balance of independence versus interdependence among components. These perspectives on coordination and pattern formation are reviewed and synthesized to formulate a novel prediction. In particular, 1/f scaling is predicted to be a pervasive property of intrinsic fluctuations produced in the balance of independence versus
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interdependence of component activities of many kinds. Evidence of pervasive 1/f scaling in human neural and behavioral activity is presented, and metastability is contrasted with alternate explanations that are specific to each domain in which 1/f scaling is observed. Uncoordinated action and the breakdown of 1/f scaling Gilden, David L.; University of Texas at Austin In the typical timing study that produces 1/f noise (Gilden, Thornton, & Mallon, 1995; Lemoine, Torre, & Delignières, 2006), a person taps out a continuous rhythmic beat without the aid of a synchronizing signal. In this paradigm the 1/f noise arises as a byproduct of the coordinated movement produced by the feeling of rhythm. Although it is not clear how the 1/f noise is itself generated or even what the feeling of rhythm is, the two phenomena are patently associated. In this communication I show how this association can be used to map out the temporal span of rhythmic feeling. Quite a bit is known about the limits to rhythmic feel, and what is known is built into the design of metronomes. Metronomes typically do not have settings that go below 40 beats per minute. From a practical point of view there is no reason to build a metronome that beats much slower, because music at slower cadence could not be conducted or counted by the musicians. The metronome limit of 40 bpm suggests that the implicit working memory system that underlies rhythmic feel has a decay half-life in the neighborhood of 1.5 seconds. In this communication I discuss timing behavior at very slow tempi, where the target beat-to-beat intervals extend beyond 1.5 s. The fluctuation spectra in these very slow regimes are not 1/f. The time series of beat-tobeat intervals shows a pronounced tendency to randomly walk when the interval exceeds 1.5 s. The random walk appears to arise as an explicit recency effect where past estimates serve as the basis for future estimates. As a practical use of this observation I show that adults with diagnosed attention-deficit hyperactivity disorder (ADHD) have a shortened temporal span in the memory system that is used in making rhythm. This work shows how timing dynamics can be used to estimate what Fraisse termed the subjective present, and it suggests that the underlying core deficit in ADHD is related to perceptual mechanisms that create the present moment. Nomothetic and mechanistic perspectives on 1/f noise Torre, Kjerstin; University Montpellier I; Eric-Jan Wagenmakers, University of Amsterdam 1/f noise or serial long-range correlation have been shown to be the typical statistical property of the outcome of many complex systems, including human motor behavior. Despite this ubiquity—or perhaps because of it—the impact of the 1/f phenomenon on human movement research has remained rather modest and unclear, and, so far, current models of motor behavior have not been designed for accounting for long-range correlation. In this communication we propose that the contribution of 1/f noise on human movement science depends to a large extent on the way one conceives this phenomenon. Especially, we contrast two current perspectives on 1/f noise. The nomothetic perspective gives general accounts of 1/f noise and refers to concepts such as complex systems, metastability, and self-organized criticality. The mechanistic perspective seeks domain-specific explanations for 1/f noise, by identifying concrete models of the underlying processes that are likely to be responsible for the correlation in the behavioral outcome. Thus, one may wonder whether the aim of serial correlation studies is to account for the prevalence of 1/f noise, or to account
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for the sensorimotor behavior under study, by taking the 1/f phenomenon into account. We argue for the usefulness of domain-specific mechanistic models of 1/f noise for theories on sensorimotor behavior. The fact that 1/f noise in given sensorimotor behaviors is sensitive to particular experimental factors tends to support this claim. Mechanistic models present the advantage to be experimentally testable and thus falsifiable, and to allow establishing links to current models of sensorimotor behavior. We support our claim by outlining a mechanistic model of 1/f noise in the time interval series produced during self-paced tapping; we show how this model can be extended to synchronization and bimanual tapping, providing a unifying account of the specific serial correlation structures evidenced in self-paced, synchronization, and bimanual tapping tasks.
Title: Motor control in older adults. Organizer: Nadja Schott, Liverpool Hope University, and Mathias Hegele, University of Dortmund Motor control in older adults Schott, Nadja; Liverpool Hope University; Mathias Hegele, University of Dortmund Movement is a critical aspect in the daily life of older adults; e.g., it is essential for the ability to maintain postural control, to walk without tripping or slipping. Dramatic changes in the properties of bone, muscle, and tendon affect motor output as individuals get older. Furthermore, there is increasing evidence that suggest that age-related changes occur in the central nervous system, underlying in part the observed changes in the control of motor units and muscles. These changes lead to slow and variable movement outputs. The purpose of this symposium is to discuss motor control issues in the elderly population: Voelcker-Rehage and colleagues present the effect of tactile stimulation on tactile discrimination and motor performance in high precision grasping in order to investigate whether aging modulates the coupling between perceptual and motor domains. Brach et al. compared goal-directed aiming movements of the dominant and the nondominant arm in order to explore potential influences of an age-related reduction in hemispheric specialization for movement control in younger and older adults. Schott et al. observed the lateralization of unimanual and bimanual hand movements in young and older adults. Sosnoff et al. examined the association of motor and cognitive variability in young and older adults on the assumptions of a shared neural resource that is adversely impacted by the aging process. Hegele and Heuer studied the influence of aging on aiming movements with altered visuomotor mappings to determine the locus of age-related deficits in visuomotor adaptation. Does high-frequency tactile stimulation improve manual dexterity in old adults? Voelcker-Rehage, Claudia; Alexander F. Knop, Mikhail Babanin, Ben Godde; Jacobs University Bremen Tactile sensitivity might be an important mechanism responsible for the precise control of grasping forces, particularly in older adults. However, also contradictory results exist and the neural control mechanisms responsible for precise manipulation of grasping forces are largely unknown. We examined the link between motor and tactile domains by applying a protocol of high-frequency tactile stimulation (tHFS) that has been shown to profoundly improve tactile acuity. Younger (18–28 years) and older (65–75 years) right-handed participants were randomly assigned to an experimental and a control group. They performed
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a pretest, 30 min of tHFS (mean frequency of 20 Hz) on the tips of their left index finger and thumb, and a posttest. Control group received no stimulation. In pre- and posttest, participants performed two motor tasks (unimanual isometric precision grip task, Purdue pegboard test) and two tactile tasks (spatial pattern discrimination, vibrotactile frequency discrimination) with their stimulated fingers. tHFS significantly improved tactile frequency discrimination, whereas motor performance as assessed with the pegboard test was impaired. Effect sizes were similar for both age groups even though absolute levels of performance in all tasks were lower for older as compared to younger adults. Additionally, older adults improved precision grip performance due to stimulation. Results show that passive tactile stimulation not only promotes sensory performance but also significantly affects fine motor control of the respective fingers. Moreover, our findings confirm the remaining plastic capacity of the older brain. Currently, we conduct a follow-up study using EEG and the test protocol mentioned above to examine the role of somatosensory cortical reorganization in the described behavioral effects. Brain laterality and motor function in the elderly Poston, Brach; Arend W.A. Van Gemmert, George E. Stelmach; Arizona State University Elderly adults often exhibit deficits in movement control and altered movement substructure during goal-directed movements of the dominant arm compared with young adults. Recent studies involving hemispheric lateralization have provided strong evidence that the dominant and nondominant hemisphere–arm systems are specialized for different aspects of movement control and that this hemispheric specialization may be reduced during normal aging. The purpose was to examine age-related differences in the movement substructure for the dominant (right) and nondominant (left) arms during goal-directed movements. Young and elderly adults performed 72 aiming movements as fast and as accurately as possible to visual targets with the two arms. A choice reaction time paradigm was used and subjects were required to move to one of two targets presented. The targets were located 13.4 cm from the start position and at angles of 5, 45, and 85 degrees to either the left or right of the subject’s midline. Online visual feedback of the movement trajectory was provided during each trial. Relative primary submovement length, relative primary submovement duration, reaction time, movement time, and normalized jerk were greater for the elderly adults, but were similar for the two arms. These findings suggest that previous work involving movement substructure and the dominant arm can be generalized to the nondominant arm. Human brain areas involved in unimanual and bimanual coordination in older adults Schott, Nadja; Liverpool Hope University The successful control of upper limb movements is an essential skill of the human motor system. Functional imaging studies have revealed recruitment of ipsilateral motor areas during the production of unimanual hand movements. This phenomenon is more prominent in the left hemisphere during left-hand movements than in the right hemisphere during righthand movements. Yet, the neural organization of bimanual actions in older adults remains an issue of debate. We used functional magnetic resonance imaging (fMRI) to investigate which brain structures might be involved in bimanual coordination, as compared to unilateral manipulation in young and older adults. A total of 43 right-handed adults participated in this study. They were split into two different groups according to age. Thus, one group
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comprised 26 older adults (12 men and 14 women) aged between 60 and 78 years (68.08 ± 5.08 years). The second group was made up of 13 university students, seven men and six women (19.54 ± 1.76 years). In the present study, subjects performed bimanual and unimanual tasks requiring cyclical flexion-extension movements of the right wrist or of both hands. Subjects exhibited activation of a typical motor network for the unimanual task in both age groups (primary sensorimotor cortices (M1/S1), lateral and medial premotor cortices [PMC, SMA], cingulate motor area [CMA], and cerebellum [ipsilateral, CB]), but several additional brain areas were involved in the elderly (ipsilateral M1, parietal cortex). For bimanual movements, young adults demonstrated bilateral activations in M1, SMA, and CB, whereas older adults showed only significant activation for M1, and frontal areas. Interestingly, we found stronger activations for unimanual as compared to bimanual coordination in older adults. It seemed to be less demanding for the motor system to control the hands bimanually compared to the unimanual performance in older adults. Coupling between cognitive and motor variability in young and old adults Sosnoff, Jacob J.; S. J. Voudrie, J. M. Samson; University of Illinois It is well known that with advanced age there is an increase in cognitive and motor variability. However, the association between cognitive and motor variability has not been established. The purpose of this investigation was to examine the association between cognitive and motor variability in young (18–30 years old, n = 36) and older adults (65–80 years old, n = 36). Subjects completed a single cognitive task and two motor tasks. The cognitive task was a modified flanker task in which subjects indicated the direction of a central cue as quickly as possible. Subjects also performed a visually guided continuous isometric force production task and a postural control task. In the force task subjects were required to produce 15% of their maximum voluntary contraction for 20 s. In the postural control task, subjects were required to stand with their feet shoulder width apart. In half of the postural trials, subjects completed a cognitive task (i.e., serial sevens). Variability of the respective performance (standard deviation of reaction time, coefficient of variation of force output and postural sway) was calculated in each task. As expected, older adults demonstrated greater reaction time variability, force variability, and postural sway compared to their younger counter parts. Cognitive variability was found to be positively correlated with force variability as well as with postural sway in the dual-task condition. When age was controlled for the correlations between cognitive and motor tasks were minimized. The novel contribution of this investigation is the discovery of an association between cognitive and motor variability, which seems to be mediated by chronological age. It is postulated that a shared neural resource that is adversely impacted by the aging process underlies the association between performance in the cognitive and motor tasks. A “strategy hypothesis” of visuomotor adaptation in older adults Hegele, Mathias; University of Dortmund; Herbert Heuer, University of Dortmund Adaptation to a visuomotor rotation is known to be impaired at older adult age. The present study examined whether these impairments are already present at preretirement age and whether they are associated with deficits in specific processes of motor control that subserve visuomotor adaptation. Therefore, three mechanisms of motor control were distinguished, which can be modulated in the service of visuomotor adjustments: closed-loop control via the online use of visual feedback, open-loop control employing an internal model of the
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visuomotor transformation, and strategic corrections based on explicit knowledge. Based on previous studies, it was hypothesized that the age-related impairment pertains primarily to strategic corrections which they are based but not to the acquisition of an (implicit) internal model of the novel visuomotor transformation. Subjects controlled a cursor on a computer screen and had to perform aiming movements to peripheral targets from a central start location as fast and as accurately as possible. Continuously available visual feedback of the cursor was experimentally manipulated introducing a visuomotor rotation of 75° CCW of cursor relative to hand movement direction. Results show an age-related deficit of adaptation and explicit knowledge already at preretirement age but no differences in adaptation aftereffects when subjects were informed that the altered visuomotor relation had been switched off. Furthermore, individual differences of the quality of explicit knowledge were associated with respective differences of adaptation, but not of after-effects. Consequently, when age groups were matched by explicit knowledge, age-related impairments of adaptation largely disappeared. This supports a view according to which age-related deficits are predominantly localized within the more cognitive aspects of visuomotor adaptation, namely in conscious, strategic processes that are responsible for the selection of appropriate action goals. Implicit adaptive adjustments seem to function independently of age.
Interdisciplinary Title: Relative age effects: Cross cultural evidence, mechanisms and future directions. Organizer: Stephen Cobley, Leeds Metropolitan University Relative Age Effects: Cross cultural evidence, mechanisms and future directions— Introduction Cobley, Stephen P.; Leeds Metropolitan University; Joseph Baker, York University; Jorg Schorer, University of Munster; Nick Wattie, Kevin Till; Leeds Metropolitan University Relative age effects (RAEs; Barnsley, Thompson & Barnsley, 1985) refer to unequal birthdate distributions of sport participants and reflect a socially created inequality that constrains participation and attainment. RAEs appear consistently, regardless of skill level, in culturally popular sports with intensive developmental infrastructures. Here, relatively younger members of annual age-group cohorts are consistently disadvantaged and less likely to maintain sport participation. Within this symposium several researchers present new data as part of an international collaboration examining RAEs. Alongside annual-age grouping, they identify and explain the mechanisms hypothesized as being responsible for RAE prevalence. The symposium also summarizes current understanding of the RAE phenomenon, addresses methodological issues and provides future directions in this field of growing interest. Maturation—the usual suspect!: RAE prevalence in the performance pathway of UK Junior Rugby League Till, Kevin; John O’Hara, Carlton Cooke, Leeds Metropolitan University; Chris Chapman, Rugby Football League, UK. Relative age effects (RAEs)—observed inequalities in participation and attainment as a result of annual age-grouping policies in youth sport—are a common problem in many sports (e.g., soccer; see Musch & Grondin, 2001). Maturational and selection mechanisms appear
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to account for these birth-date discrepancies; however understanding how they manifest and operate—even in physically dependent sports (e.g., Rugby League)—is not clear. The purpose of this study was to examine birth date distribution, physical maturity, height, and body mass in regionally and nationally selected UK junior Rugby League players. Between 2005 and 2007, birth date, height, sitting height, and body mass were collected and age at peak height velocity (PHV) calculated (Mirwald et al., 2002) in 12- to 16-year-old players involved in the UK’s Rugby Football League National (n = 208) and Regional (n = 473) performance pathways. Chi-square analyses identified significant uneven birth date distributions, with 54% of National (χ2 = 107.2, p < 0.0001) and 47% of Regional players (χ2 = 140.9, p < 0.0001) born in the first quartile (i.e., Sept to Nov) alone. Related to height, 95% of National and 92% of Regional players were taller than the age-matched 50th percentile of UK reference values. And similarly, 97% of National and 96% of Regional players were above the UK’s age-matched 50th percentile for body mass. National (13.52 ± 0.58) and Regional (13.62 ± 0.6) players’ age at PHV also occurred significantly (p < 0.0001) earlier than UK reference values (Billewicz et al., 1981) of 14.1 ± 1.0 years. Although recognizing the physical demands of Rugby league, findings suggest that talent selection is overwhelmingly biased toward the relatively older, taller, heavier, and earlier maturing youngster within an annual cohort. Thus, younger and later maturing junior rugby league players are disadvantaged in selection to the performance pathway due to a lack of physical development. Are other player characteristics influential?: Evidence from an in-depth examination of elite German handball Schorer, Jörg; University of Münster; Steve Cobley, Leeds Metropolitan University; Helge Bräutigam, University of Münster; Dirk Büsch, Institute for Applied Training Science– Leipzig; Joseph Baker, York University Previous research has suggested that the magnitude of RAEs may relate to physically demanding contexts and playing positions (e.g., Grondin & Trudeau, 1991). In European handball backcourt positions benefit from physical characteristics (e.g., height) suggesting stronger RAEs may occur. Additionally, there are tactical advantages for left-handers to play on the right side of court. However, as only 10–13% of the population is left-handed (Raymond et al., 1996), it can be hypothesized that RAEs may be smaller or not apparent for these positions. In testing these hypotheses, birth-date, playing position, handedness, and nationality of 1,289 players from the first German handball league for the seasons 2004/05 and 2007/08 were collected from internet sources. Results revealed that playing position affected the distribution of players across the birth quartiles. The backcourt positions generally showed an over-representation in the first two quarters; however, other positions (e.g., circle players or goalkeepers) showed an opposite trend, at a descriptive level. Additionally, differences in the distributions for players from the left-side (i.e., right-handers) and the right-side (i.e., left-handers) of the court were demonstrated. Distributions for international and national players differed as well in some cases. These results provide consistent evidence that playing position and laterality affect the strength of RAEs in handball. Were RAEs a problem in the past?: Evidence from a historical analysis of elite German soccer Cobley, Stephen P.; Leeds Metropolitan University; Jörg Schorer, University of Münster; Joseph Baker, York University
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Previous studies have suggested that RAEs are only a relatively recent phenomenon (Daniel & Janssen, 1987; Wattie et al., 2007). The present study tested this notion by tracking the existence of RAEs across the history of elite German soccer. An additional objective was to consider the social-cultural mechanisms possibly related to RAE presence. All Germanborn players (n = 4,650), head coaches (n = 263) and referees (n = 272) who represented professional soccer clubs or officiated in the Bundesliga from 1963-4 to 2006-7 were examined. Also, soccer participation patterns across Germany for the period 1950 to 1990 were obtained from the German Soccer Association. Chi-square analyses generally showed that when players were distributed into half decade groups (e.g., players born between 1941 and 1945, n = 361), RAEs were present across the history of the Bundesliga, irrespective of dates used for annual age grouping in junior/youth soccer (χ² ranged between 8.93 to 23.76 all p < .05). RAEs were also apparent for head coaches (χ² = 9.44, p = .02, w = 0.19, 1-? = 0.73). With many coaches being former players, inequalities associated with annual age-grouping appear to extend beyond a playing career. Officiating was not affected (χ² = 1.52, p = .68), with referees suggested to emerge from an alternative development pathway. Participation data indicated consistent and progressive growth from 1950 to 1990 (e.g., number of registered teams in 1950 = 54,053; 1990 = 121,912), suggesting that increased popularity of soccer may have propagated RAEs over time, through intensification of competition and selection mechanisms in youth soccer structures. To conclude, RAEs have influenced the likelihood of attaining elite player and coaching status since the origins of the Bundesliga. Social structures and social cultural mechanisms are likely to be responsible. The past, present, and future of relative age research in sport Wattie, Nick; Leeds Metropolitan University; Joseph Baker, York University; Stephen P. Cobley, Leeds Metropolitan University Typical relative age research has focused solely on the immediate and long-term consequences of annual age-grouping policies in youth sport across cultures and contexts. Studies consistently highlight that relatively older athletes within annual cohorts are more likely to participate and be selected for representative youth sport, resulting in an increased likelihood of reaching the elite sporting echelons. More recently, research has begun to broaden its focus by examining other outcomes, including differences in injury risk, playing time, draft rank for professional leagues, and player salary. Further, later research has progressed our understanding of the mechanisms initiating, perpetuating, and moderating the risk of relative age effects. A review of research in this area indicates that consistent problems exist relating to operational definitions and terminology used in this area of research and that our understanding of this phenomenon is far from complete. For example, there is a dearth of relative age research examining women’s sports contexts. Further, there is little evidence of collaboration between practitioners and policy makers in an effort to eliminate relative age effects. Based on recent findings, a greater understanding of relative age can also be obtained by comparing different sociocultural, and sport, contexts as important constraints of relative age effect characteristics, and progression throughout sport involvement. Perhaps more surprising is the emerging hypothesis that current annual-age grouping policies and early talent identification systems, initially advantageous for relatively older athletes, may actually be detrimental to long-term skill development and sporting attainment. An examination of this hypothesis would be particularly beneficial. An overview of methodological limitations in prior research and a summary of avenues for future research will be outlined in the presentation.
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Title: Models of expertise development in sport: Supporting evidence. Organizer: Paul Ford Models of expertise development in sport: supporting evidence: Introduction. Ford, Paul R.; Liverpool John Moores University A number of models have attempted to map out the ideal pathway for skill development in sport from early childhood to adulthood. Sports governing bodies around the world have been quick to apply these models. Many of these organizations have done so without a clear understanding of the strengths and weaknesses of the models proposed. In this symposium we present evidence for various models of skill development in sport. Bruner and colleagues will present a citation network analysis review of the evidence for these models. This review shows that the model with the greatest amount of supporting evidence is Côté’s 1999 developmental model of sport participation; i.e., between 6 and 18 years old, expert athletes progress from participating in play activity in a number of sports to practice activity in their primary sport. Next, Ford and Williams examine this model in European soccer and report sport and cultural specific revisions to the model; e.g., expert soccer players progress from soccer-specific play activity within the sport, rather than between sports, to practice activity in soccer. The model contains the further prediction that expert adult athletes participate in large amounts of sport-specific practice in their primary sport. Hodges and colleagues present a number of studies involving triathlon where they have shown that changes in performance times can be reliably predicted from hours accumulated in sport-specific deliberate practice activities and that commitment is the driving force behind engagement in this practice activity. Finally, even if a sport organization implements an evidence-based model of skill development, a number of secondary factors that influence athlete development must be considered. Baker will present a number of studies in which the secondary influences of relative age and population of birthplace are examined. Models of expertise development in soccer: A special case? Ford, Paul R.; A. Mark Williams; Liverpool John Moores University Models of expertise development require supporting evidence from various sports, cultures, and countries before being implemented. Two main evidence-based models of participant development exist, both emanating from North America. The model evidenced by Côté (1999) contains predictions that athletes who attain expert status engage in playful activities across a number of sports between 6 and 12 years of age, before specializing in their primary sport and engaging in equal amounts of play and practice between the ages of 13 and 15 years. In contrast, the model of expertise development proposed by Ericsson et al. (1993) predicts that performers who attain expert status should specialize in a domain at an early age and engage only in large amounts of domain-specific, deliberate practice. We present a number of recent studies in which the predictions of these two models have been tested in European professional soccer. Our findings demonstrate that the participation histories of expert soccer players do not directly follow the predictions of either of these models. We have shown that between the ages of 6 and 12 years elite European youth soccer players participate in large amounts of soccer-specific playful activity and, depending on the culture, in varying amounts of soccer-specific team practice. These expert soccer players engage in relatively few or no playful activities across other sports between 6 and 12 years of age. They participate in greater amounts of soccer-specific team practice compared to soccer-specific play between
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the ages of 13 and 15 years. European expert soccer players progress from soccer-specific play activity within the sport, rather than between sports, during the early years, to practice activity within the primary sport later in development. Our findings suggest that further research is required across sports, cultures, and countries to test the predictions of current participant development models. Supporting evidence: Commitment and deliberate practice among triathletes Hodges, Nicola J.; Lina Augaitis, Christopher Edwards, Peter Crocker; University of British Columbia In previous work Hodges and colleagues have shown that performance times in triathlons and long distance swim events can be reliably predicted from hours in sport-specific deliberate practice activities, but not fitness or other general sport activities. In the current study we examined whether commitment to the sport could be a possible mediator of practice and subsequently performance. Recreational triathletes (n = 142) were surveyed about their current practice habits as well as ratings for current levels of commitment based on Scanlan et al.’s 1993 sport commitment model. Practice hours in the past year based on seasonal variations in practice; i.e., pre-race, race, off-season estimates showed a moderate sized correlation with commitment, r(134) = .42. Average number of hours/week training yielded a correlation of r(141) = .34. Commitment and accumulated practice showed a correlation of r(141) = .30. Although cause and effect statements are difficult to make from this type of research, it is tempting to speculate that these markers of commitment predict practice behaviors and hence performance which will be examined. However, because commitment levels were most highly correlated with weekly and yearly practice, as opposed to practice across the athlete’s career, there might be reason to suspect that commitment is only a transient measure of current levels of performance investment. In future research it will be important to track practice behaviors and sport commitment or other motivation-related variables concurrently to try to ascertain the direction of the relationship and whether commitment to the sport is the driving force behind engagement in practice. Secondary influences on sport skill acquisition Baker, Joseph; York University Researchers examining the development of elite athletes have identified a range of environmental and genetic constraints, which can generally be divided into those having a direct influence on performance primary factors and those having an indirect effect secondary factors (Baker & Horton, 2004). Although a great deal of research has established the significance of primary factors such as training and genes, secondary factors are often overlooked. Nonetheless, research suggests these factors are important constraints on athlete development. This presentation will review a series of studies examining two of these factors: relative age and size of birthplace. Relative age effects refer to chronological age discrepancies between individuals within an annually age-grouped cohort. Since their identification in sport in the early 1980s, relative age effects have been consistently noted as influences on development, most likely by providing greater opportunity to the relatively older while disadvantaging the relatively younger. However, these effects are moderated by several factors, including age, depth of competition, and cultural importance. Similarly, characteristics associated with the size of an athlete’s early developmental environment
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also seem to play a role in predisposing them to greater levels of skill development. Several studies have suggested an optimal environment size for nurturing athletic talent; however, recent research indicates that this relationship may also be moderated by social and cultural factors. Even though the existing research suggests that these effects are very robust under specific conditions, a great deal of research remains to be done in order to fully understand the subtlety of these effects and the mechanisms by which they occur. An appraisal of lifespan developmental models in sport through citation network analysis Bruner, Mark; Jean Côté, Karl Erickson, Brian Wilson, Queen’s University A number of models have been proposed to depict a participant’s development in sport across the lifespan. However, minimal research has attempted to examine the models collectively. The purpose of this study was to evaluate the existing models of lifespan development in sport through the use of citation network analysis. Unlike previous review strategies, citation network analysis evaluates the cognitive structure of a field of study such as the prominence of specific articles and scholars (Moore, Shiell, Hawe, & Haines, 2005). Based upon five criteria, seven articles representing seven distinct models of lifespan development in sport were selected as the base of the article population. A list of all peer-reviewed journal articles that cite at least one of these seven model articles was compiled, resulting in a total population of 73 articles including the seven model articles. Each article was then classified by type using APA guidelines (e.g., empirical, review) and checked to determine the citation of any other articles in the total article population. Based on this citation practice data, a citation network of the article population was generated using UCINET network analysis software. Results revealed that Côté’s developmental model of sport participation (DMSP; 1999) was the most central article, with a centrality score of 50, more than three times higher than the next most cited article. The 50 articles citing Côté’s 1999 model included 18 quantitative, 17 qualitative, 8 review, 4 theoretical, 2 methodological, and 1 commentary article. In comparison to the other six models, the DMSP also received the most empirical support from other articles, with 16 articles empirically testing the model. These findings highlight the need for further empirical research of the DMSP and the other models in moving towards the creation of an integrated theory in lifespan development in sport.
Title: Posture and perceptual performance in typical and atypical populations. Organizer: Mike Wade Posture and perceptual performance in typical and atypical populations: Introduction Wade, Mike; Thomas A. Stoffregen, University of Minnesota Research and theorizing about visual performance has focused primarily on both the cognitive and neural processes involved. James Gibson (1966) proposed a revised and expanded definition of the visual system that was directly coupled to a more encompassing perceptionaction system. Postural control has typically been portrayed as an autonomous system. This interdisciplinary symposium presents three papers with different groups of participants that include developmental, clinical, and social foci that empirically support the idea that vision and posture are dynamically linked within an integrated perception-action system.
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Postural support for personal performance and interpersonal coordination Giveans, M. Russell; Christie Pelzer, Allison Smith, University of Minnesota; Kevin Shockley, University of Cincinnati; Thomas A Stoffregen, University of Minnesota When two standing people converse with each other there is an increase in their shared postural activity, relative to conversation with different partners (e.g., Shockley et al., 2003). Why does this happen? We evaluated the hypothesis that interpersonal postural coordination has a functional component. To do this, we contrasted dyadic suprapostural tasks with variations in the size of visual targets that are used in the conversation task. Subjects were run in pairs. Each member of a pair looked at one target, a cartoon-like drawing. The two drawings differed in subtle ways, e.g., whether or not a man wore a hat. Each individual could see only one drawing, and the task was for the partners to identify and count discrepancies between the two drawings. We varied the size of visual targets. Small targets were approximately 0.25 m2, and large targets were approximately 1.0 m2. In a within-subjects design, we used four conditions: Each subject saw a large target big-big, each subject saw a small target small-small, and members of a pair saw different-sized targets big-small, and small-big. As individuals, subjects moved more when viewing a large target than when viewing a small target. Target size also influenced interpersonal coordination. We found an interaction between an individual’s target size and the size of the partner’s target, on the variability of hip motion in the ML axis. Interpersonal coordination was also assessed using cross-recurrence analysis. Variations in target size influenced four parameters of dyadic head movements: percent recurrence, percent determinism, maxline, and entropy. In contrast to previous studies, there were no effects on dyadic movement of the hips. The results suggest that postural activity was simultaneously and differently influenced by visual constraints target size and interpersonal constraints social interaction. Postural support for visual performance in children at risk for developmental coordination disorder Jordan, Azizah; Michael G. Wade, Ken Yoshida; University of Minnesota We analyzed postural sway in both typically developing children (TDC) and a group at risk for developmental coordination disorder (DCD). Participants engaged a visual performance task requiring them to either look at a blank white board control condition, or count the number of designated alphabet letters on a similar white board containing letters of the alphabet presented in a random sequence. Postural motion was recorded in two planes, anterior/posterior and medial/lateral, during two 60-s trials presented at random in both the control and experimental conditions .The results showed a reliable interaction between participants and the conditions. TDC children reduced their postural motion in the letter counting condition, whereas the DCD children increased their postural motion in the same experimental condition. These data are discussed in the context of the role of posture in attempting to improve visual performance and suggest that one signature of DCD maybe poor perception–action coupling in suprapostural tasks requiring perceptual effort.
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Postural support for visual performance Yoshida, Ken; M. Russell Giveans, University of Minnesota; Benoit G. Bardy, University of Montpellier; Thomas A. Stoffregen, University of Minnesota Stance is not maintained for its own sake, but for the sake of other behaviors that are afforded during stance. Stance typically co-occurs with other, nonpostural activities, such as reading, walking, and so on. To avoid falling, the center of mass must be maintained over the base of support the feet, in stance. This criterion differs qualitatively from the performance criteria for most nonpostural tasks (e.g., reading rate or comprehension, walking speed). It is commonly assumed that postural control and simultaneous suprapostural activities compete for a limited-capacity pool of central processing resources, leading to the prediction that body sway should increase, suprapostural performance should decline, or both, when postural control and suprapostural activities are combined. In several studies, we have shown that sway amplitude decreases as a function of precision demands of suprapostural visual tasks. These studies support the general hypothesis that posture is controlled, in part, to facilitate performance of suprapostural activities.
Motor Development Title: Motor development in atypical populations: “deficit” or “adaptation”? Organizers: Matthieu Lenior, Ghent University, and Frederik Deconinck, Manchester Metropolitan University Motor development in atypical populations: “deficit” or “adaptation”?— Introduction Lenoir, Matthieu E.M., Ghent University; Frederik J.A. Deconinck, Manchester Metropolitan University It is common practice in motor development research in atypical populations to compare the subjects’ behavior with typically developing (TD) peers. Regardless of the specific features of these populations, a central question is whether these differences should be considered as a developmental deviation/retardation, or as an adaptation to their specific condition. Either perspective has different implications with regard to theory and clinical practice (Latash & Anson, 1996). This symposium tackles this issue by focusing on atypical populations with a range of constraints, i.e. “deficits” at the level of morphology, physiology, neurology, information-processing, etc. D’Hondt will focus on gross and fine motor skills in children with overweight and obesity, which is in essence a morphological constraint that primarily should constrain gross motor skills. The information-processing capacities of children with developmental coordination disorder will be addressed in Deconinck’s talk on visuomotor coordination and balance control during an obstacle-crossing task. Savelsbergh’s contribution deals with the question of how children with spastic hemiparetic cerebral palsy extract and
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use dynamic information from the environment for the on-line guidance of goal-directed behavior, and how they take into account the limitations of their specific condition. Finally, Beverly Ulrich will discuss gait characteristics in children with Down syndrome, a condition that affects the person at the neurological, morphological, as well as physiological level. This symposium aims at unifying knowledge from different atypical populations and to investigate to what extent the deficit/adaptation discussion is an issue that crosses the borders between these specific populations. Relationship between motor skill and body mass index in 5- to 10-year old children D’Hondt, Eva M.G.; Benedicte I. Deforche, Ilse M. De Bourdeaudhuij, Matthieu E.M. Lenoir; Ghent University Prevalence levels of childhood overweight and obesity are increasing. In the past decade, numerous studies have established that overweight and obese children systematically show lower test scores on physical fitness items (Deforche et al., 2003). However, motor skill performance and quality of movement coordination have not been extensively documented yet. The focus in these studies is mainly on gross motor skills, and the observed differences are primarily explained from a mechanical point of view (Okely et al., 2004). Therefore, the purpose of this study was to investigate both gross and fine motor skill in overweight and obese children compared to normal-weight peers. In this way, we wanted to verify if group differences in motor skill would also appear if only a limited part of the body mass is involved. A series of tests was used to assess gross motor skill, fine motor skill, as well as the combination of both. Our results revealed that test scores of gross and combined motor skill were significantly better in normal-weight and overweight children as compared to their obese counterparts. But also for fine motor skill a strong tendency towards a weaker performance of obese children was observed. So, the present study demonstrated that childhood obesity—but not overweight—is associated with a lower general motor skill level. This suggests the existence of a certain threshold from which movement difficulties appear. With respect to the strong tendency towards weaker fine motor skill performance of obese children, further research needs to consider whether the lower motor skill level of obese children is caused solely by the excessive mass of body and body segments or could, in addition, be explained from a perceptual-motor point of view. Balance constraints on walking in children with developmental coordination disorder: The case of obstacle crossing Deconinck, Frederik J.A.; Manchester Metropolitan University The basic, unobstructed gait pattern of children with developmental coordination disorder (DCD) has been shown to be atypical, sharing some characteristics with immature gait, e.g., higher cadence, crouched posture, decreased knee extension, flat foot placement (Deconinck et al., 2006). In this study it was examined whether these gait differences could be explained by a dynamic balance problem by studying how children with DCD adapt their basic gait pattern to the presence of an obstacle. Obstacle negotiation and crossing behavior of 12 children with DCD (10 boys, 2 girls, mean age: 7.8 ± 0.5) was compared with 12 matched typically developing TD peers (10 boys, 2 girls, mean age: 7.7 ± 0.6) in three walking conditions: (1) unobstructed walking, (2) stepping over a low cord 5% of leg length, and (3) stepping over a higher cord 30% of leg length. The results showed similar obstacle approach and negotiation behavior in both groups. When the obstacle was present, a slower approach velocity was adopted by DCD and TD-children. Approach distance, i.e., the distance of the last foot
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placement to the obstacle, did not differ between groups irrespective of the obstacle height. Further, both groups were able to adapt the end-point movement of the feet appropriately by scaling lead and trail foot clearance in proportion to the height of the obstacle. During the crossing stride, the relative duration of the swing increased for higher obstacles, however to a lesser extent in children with DCD. Additionally, the crossing stride was associated with more mediolateral sway of the center of mass in this group. These findings indicate that visuomotor coordination of children with DCD was not different from their peers in this obstacle avoidance task. However, the increased constraints on balance provoked by the obstacle did put the body stability of children with DCD at greater risk and resulted in subtle changes to the crossing stride. Information–movement coupling in children with spastic hemiparetic cerebral palsy Van Kampen, Paulien M.; Annick Ledebt, VU University Amsterdam; Geert J.P. Savelsbergh, VU University Amsterdam and Manchester Metropolitan University The goal of the experiment was to determine the presence of adjustments in walking behavior of children with spastic hemiparetic cerebral palsy (SHCP) during the interception of a ball. Second, to examine whether the angle between the ball and the participant is kept constant. This would support the use of the so-called bearing angle BA strategy in interception of the object (Lenoir et al., 2002). Children with left hemisphere damage intercepted a ball from a conveyor belt with their impaired or less-impaired hand. Three different ball approach velocities were used. The participants walked from a distance of 4 m perpendicularly to the belt. The results showed that the walking velocity was adjusted to the ball velocity. When the ball was grasped with the impaired hand, children initially moved faster to the interception point, while they walked significantly slower closer to the belt. The BA showed less variation over the trajectory when the children grasped with their less-impaired hand or when the ball velocity increased (Van Kampen et al., in press). It was concluded that children with SHCP were able to take their impairment into account as indicated by adjustments in walking behavior. However, these adjustments in walking velocity were not sufficient to compensate totally for the limited reaching ability in the impaired hand. As a result of these adjustments, the amount of variation from the constant BA seemed to deviate more from typically developing children when grasping with impaired hand than when grasping with less impaired hand. Gait characteristics in persons with Down syndrome illustrate normal motor behavior processes Ulrich, Beverly D.; University of Michigan In my talk I will use examples from my research involving people with Down syndrome (DS) to address the issues of why particular patterns of motor behavior emerge, from a theoretical as well as mechanistic perspective. I will argue that understanding the behavior from these viewpoints assists in determining whether interventions to change the behavior may be helpful or, perhaps, harmful. Data to support these arguments will focus on gait patterns, in particular. People with DS differ significantly from their peers with typical development (TD) on a host of gait characteristics. Some of these differences disappear when raw data are normalized to individuals body sizes, e.g., stride frequency, stride length. Others are not explained so easily but may be attributed to unique neural or physiological constraints, e.g., flat footedness, wide stance (Black et al., in review; Smith et al., 2007; Ulrich et al., 2004). One important question to be addressed is whether the behavior observed is optimal
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for this system (i.e., persons with DS) or could behavior be enhanced with appropriate intervention. I will expand on these issues by discussing the biomechanical basis for wide stance as a strategy discovered by persons with DS to optimize stability when walking. In this case, intervention to change this is unwarranted (Kubo & Ulrich, 2006). Alternatively, I will outline the rationale for intervening to reduce delayed walking onset in this same population and share empirical evidence of the success of these experiments (Ulrich et al., 2001, 2008; Wu et al., in press).
Sport and Exercise Psychology Title: Acute Exercise and Cognitive Performance: Recent Findings and Future Directions. Organizer: Jennifer Etnier Acute exercise and cognitive performance: Recent findings and future directions— Introduction Etnier, Jennifer; University of North Carolina at Greensboro Nearly 200 studies have been conducted to examine the effect of acute exercise on cognitive performance. These studies have been designed to test a variety of theories including the inverted-U hypothesis, the central fatigue hypothesis, and attention allocation models. The designs of these studies have been remarkably varied and include studies that have looked at potentially important moderators of the effect such as the intensity of the exercise, the cognitive task used, and fitness levels. The commonalities in these studies are that most use young adults as participants, use aerobic forms of exercise, and compare performance at rest with performance at one or more intensities of exercise. In narrative reviews, researchers have typically concluded that acute submaximal exercise has a positive effect on cognitive performance (Brisswalter et al., 2002; McMorris, & Graydon, 2000; Tomporowski, 2003). Thus, it is important to continue to conduct research in this area to further our understanding of the relationship. The purpose of this symposium is to present new findings and to suggest potential future directions for research in the area of acute exercise and cognition. Jennifer Etnier will present findings from a recent meta-analytic review that allows for an understanding of the magnitude of the effect of acute exercise on cognition and allows for an exploration of how particular relevant variables moderate the effect. Jeff Labban will discuss the rationale for acute exercise benefiting long-term memory and will present findings that address this effect and how the timing of the exercise bout relative to the consolidation period moderates the effect. Yu Kai Chang will discuss mechanisms supporting the possibility for resistance exercise to benefit cognitive performance and will present relevant findings from a study with middle-aged adults. Jennifer Gapin will discuss the theory and mechanisms that support the potential for acute exercise to benefit the cognitive performance of children with attention deficit hyperactivity disorder. Effects of acute exercise on long-term memory Labban, Jeffrey D.; Jennifer L. Etnier; University of North Carolina at Greensboro There is a growing body of research examining the relationship between acute exercise and cognition. Most studies have examined tasks such as reaction time, executive functioning, or working memory. However, recent studies by Potter and Keeling (2005) and Ahmadiasl
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et al. (2002) have shown that acute exercise positively impacts aspects of long-term memory. The purposes of this study were to examine the effect of a moderate bout of acute aerobic exercise on long-term memory and to determine if the effect is influenced by the order in which the exercise is introduced relative to the consolidation phase of the memory task. Adults (n = 48) were randomly assigned to one of three conditions: exercise-rest, rest-exercise, or rest-rest. Long-term memory was assessed using the Standard New York University Paragraphs. Participants were read two separate paragraphs (exposure) and then, following a 35-min delay, were asked to recount the paragraphs. Participants in the exercise-rest group exercised prior to exposure and rested quietly during the delay. Participants in the restexercise group rested quietly prior to exposure, and completed the exercise bout during the delay. Participants in the control condition rested quietly prior to exposure and during the delay. The exercise condition consisted of a 30-minute bout on a cycle ergometer: 5-min warm-up, 20 min of moderate exercise (between 13 and 15 on the Borg RPE scale), and a 5-min cool-down. The rest condition consisted of sitting quietly in the laboratory. Results indicated that there were significant differences in delayed recall performance between the groups, F(2, 45) = 4.37, p < .05. Post hoc analyses indicated that the exercise-rest group (M = 15.50, SD = 4.13) performed significantly better (p < .05) than either the control group (M = 11.13, SD = 4.27) or the rest-exercise group (M = 12.19, SD = 4.68), which were not significantly different from one another. These results indicate that long-term memory may be positively influenced by an acute bout of exercise, and may be moderated by the order in which exercise is introduced. Relationship between physical activity, behavioral symptoms, and executive function in ADHD children Gapin, Jennifer I.; Jennifer L. Etnier, University of North Carolina at Greensboro Attention deficit hyperactivity disorder (ADHD) is one of the leading childhood psychiatric disorders and is a costly public health problem. ADHD causes cognitive impairments and while stimulant medications are effective in treating core symptoms of ADHD, there is little known about their long-term effects and they can cause numerous deleterious side effects. Research suggests that acute exercise positively impacts some of the same mechanisms that have been implicated in ADHD suggesting that exercise might serve as an effective adjuvant therapy. One common mechanism is brain derived neurotrophic factor (BDNF). Stimulant medications increase BDNF and there are significant correlations between genetic variations in BDNF and vulnerability to ADHD. In animals, exercise is linked to increased BDNF and is associated with improved performance on cognitive tasks. Recent human studies show significant increases in BDNF following acute bouts of exercise. A second common mechanism is catecholamines. ADHD is associated with decreased levels of catecholamines, specifically dopamine, that impact working memory, arousal, and attention. Exercise is widely known to stimulate the noradrenergic system, which influences catecholamine function. Evidence from animal models shows that acute exercise benefits dopamine release and turnover. An additional commonality is related to executive function. ADHD is characterized by deficits in executive function as compared to control participants. Research with older adults and children without ADHD shows that exercise selectively improves performance on executive function tasks. Despite evidence and rationale supporting the potential for exercise to benefit children with ADHD, there is very little research in this area. Behavioral interventions that augment traditional forms of ADHD treatment are needed, and exercise is a simple, widely available, and well-tolerated intervention for ADHD. Consequently, more research looking at the effects of acute exercise on cognition in ADHD populations is warranted.
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Effects of an acute bout of localized resistance exercise in middle-aged adults on cognitive performance Chang, Yu Kai; Jennifer L. Etnier, University of North Carolina at Greensboro A considerable number of studies have demonstrated a positive relationship between acute exercise and cognition. However, this literature is limited by a focus on young adults and chronically ill older adults and the effects in healthy middle-aged adults have not been examined. In addition, the existing research on the cognitive benefits of acute exercise has only examined aerobic exercise, and research has not yet tested whether or not similar effects can be observed following resistance exercise. It is likely that resistance exercise might benefit cognitive performance in a manner similar to aerobic exercise because both forms of exercise have an effect on arousal and on plasma catecholamines, which are mechanisms proposed to explain the relationship between acute exercise and cognition. The purpose of this study was to use a randomized controlled design to examine the effect of an acute bout of resistance exercise on cognitive performance in healthy middle-aged adults. Forty-one adults (M age = 49.10 years, SD = 8.73) were randomly assigned to either resistance exercise or a control condition. The Stroop Test and the Trail Making Test (TMT) were completed at baseline and immediately following performance of the treatment. Results indicated that resistance exercise significantly benefits speed of processing (Stroop Word and Stroop Color), and that there is a trend towards resistance exercise benefiting performance on an executive function task (Stroop Color-Word) that requires shifting of the habitual response. However, the results for the TMT were not significant, which demonstrates that acute resistance exercise has a limited effect on inhibition. In summary, the present findings extend the literature by indicating that an acute bout of resistance exercise has a positive impact on automatic cognitive processes and on particular types of executive function in middle-aged adults. Further research is recommended to confirm the reliability of these results, to further examine doseresponse issues, and to enhance our understanding of potential mechanisms. A meta-analysis of the literature on acute exercise and cognitive performance Etnier, Jennifer; Yu Kai Chang, Jennifer I. Gapin, Jeffrey D. Labban; University of North Carolina at Greensboro Nearly 200 studies have been conducted to examine the effects of acute exercise on cognitive performance. Narrative reviews have been conducted to further our understanding of this literature (Brisswalter et al., 2002; McMorris, & Graydon, 2000; Tomporowski, 2003). However, because the empirical literature is so disparate, drawing conclusions has been challenging. The purpose of this meta-analytic review is to estimate the magnitude of the effect size (ES) of acute exercise on cognitive performance and to allow for an exploration of potential moderators of the effect. Studies were coded and ESs (corrected for sample size) were calculated for 209 effects from 23 studies randomly selected from the literature. The overall average ES was 0.22 (95% CI = 0.14 to 0.31), suggesting that acute exercise has a significant small positive effect on cognitive performance. ESs differed significantly as a function of the type of cognitive performance task with moderate effects observed for executive function (M = 0.45, 95% CI = 0.24 to 0.66) and crystallized intelligence (M = 0.46, 95% CI = 0.28 to 0.63), small effects for information processing (M = 0.19, 95% CI = 0.06 to 0.32), and negligible effects for reaction time (M = −0.03, 95% CI = −0.20 to 0.13). ESs also differed significantly as a function of the exercise intensity level (categorized using ACSM guidelines) with larger ESs evident for light (M = 0.29, 95% CI = 0.16 to 0.43), moderate
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(M = 0.36, 95% CI = 0.19 to 0.54), and hard (M = 0.36, 95% CI = −0.05 to 0.77) exercise and negligible ESs for very light (M = −0.05, 95% CI = −0.19 to 0.10) and maximal (M = 0.07, 95% CI = −0.15 to 0.29) exercise. Time of test administration relative to the exercise bout also impacted ES with smaller ESs found during exercise (M = 0.13, 95% CI = 0.02 to 0.25) than immediately postexercise (M = 0.31, 95% CI = 0.16 to 0.47) or at other times postexercise (M = 0.44, 95% CI = 0.26 to 0.63). These results suggest that acute exercise benefits cognitive performance and that larger ESs are observed for particular types of cognitive tasks administered following exercise at light, moderate, and hard intensities.
FREE COMMUNICATIONS: VERBAL AND POSTER Journal of Sport & Exercise Psychology, 2008, 30(Suppl.), S28-S37 © 2008 Human Kinetics, Inc.
Interdisciplinary* Performance excellence among first responders: Implications for sport psychology specialists Chung, Yongchul; Regina Avery-Epps, Sherry Springs, Younho Seong; North Carolina Agricultural & Technical State University Developing excellence among first responders (i.e., firefighter, police officer, and EMS personnel) has much in common with developing excellence among athletes. Excellence in first-responding operations, just as in sport, requires tremendous mental and physical strength. Like an athlete in highly competitive events, first responders must decide the best course of action in a high-stress environment. More often than not, first responders must maintain their physical stamina and mental concentration for an extended period of time. Historically, the field of sport psychology has maintained an interest in performance excellence, focusing on optimizing the performance of athletes by implementing mental skills training (Miller & Kerr, 2002). As a result, the field has been saturated with theoretical and practical knowledge with regards to developing mentally tough athletes, as well as the mental skills these athletes used to achieve optimal psychological states (Williams & Krane, 2001). Based on what has been learned about excellence in the sport context, contemporary sport psychology researchers have begun to move into studying excellence in other domains, such as performing arts, police, military training, and surgical training. The present study targeted first responders responsible for providing first-hand aid during the massive disasters. Six veteran first responder trainers participated in the interview study. During the interviews, the participants described what it meant to be a champion in their first responding profession and elaborated on how to develop excellence in other first responders. The results showed some clear similarities, as well as unique differences, between performance excellence in sport and among the first responders. It was concluded that there are extensive opportunities for sport psychology researchers to contribute to the advancement of first responders training. Finally, the practical implications relative to the unique challenges when transferring sport psychology knowledge to other domains will be addressed. The capabilities of young children to collapse a portable crib Fairbrother, Jeffrey T.; University of Tennessee-Knoxville; Christine A. Readdick, Florida State University; John B. Shea, Indiana University This study describes the forensic analysis of a portable crib involved in the death of a 17-month-old child. The primary question addressed was whether a child comparable in age and size to the victim could self-collapse the crib from within. The participants ranged in age from 17 to 24 months. The study was conducted in two phases, one involving the
*The abstracts are alphabetically arranged by the first author’s surname within each of the four sections—Interdisciplinary, Motor Development, Motor Learning and Control, and Sport and Exercise Psychology.
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measurement of torque generation capabilities and one involving observation of children in the crib. During the torque measurement phase, participants engaged in free play on an apparatus designed to match critical features of the crib. Torque measurements were obtained for two male and two female children. All four children were capable of generating enough torque to rotate the railings of the crib. The observation phase included six children, three male and three female. Four of the children had also participated in the torque measurement phase. Observation of the behaviors of the children confined to the crib revealed that the knobs normally used to rotate the railings did not reset to the locked position after slight rotations by the children. This characteristic facilitated the incremental rotation of the railings. Observation also revealed that the children engaged in a systematic exploration of the features of the crib. In addition, it appeared that the children tested various escape strategies to learn how to escape confinement. There were also several episodes of rail hanging and jumping behaviors that were consistent with actions that could plausibly have resulted in the collapse of the crib. These findings suggested that the crib could be collapsed by a child within its confines. Effects of peppermint scent inhalation on diminishing smoking cravings and withdrawal symptoms Felbaum, Daniel; Jarred Bloom, Trevor Cessna, Rosanna Drake, Bryan Raudenbush; Wheeling Jesuit University A variety of pharmacological methods have been proven effective in alleviating the symptoms of smoking cravings and withdrawals. The present study assessed a more natural approach by using peppermint scent as a potential cravings, urges, and withdrawal symptoms inhibitor. In a within-subjects design, participants completed three conditions: peppermint inhalation use in lieu of smoking (PI), control ad-libitum smoking (CS), and abstinence from smoking (AS). While undergoing each of these conditions, participants completed a series of surveys three times each day. The surveys included the Profile of Mood States, Cigarette Craving Survey, Smoking Urges Survey, Cigarette Withdrawal Scale, Peppermint Inhaler Use Tally, and Cigarette Use Tally. Results indicated differences in smoking urges, smoking cravings, and smoking withdrawal symptoms, such that CS < PI < AS. In terms of anxiety, vigor, anger, and confusion, there was no significant difference between PI and CS conditions. There were no significant differences for smoking urges, smoking cravings, and smoking withdrawal symptoms between the PI and CS conditions. There were significantly lower ratings between CS versus AS. This study provides evidence that inhaling peppermint scent can achieve similar results in smoking cravings and withdrawal symptoms when compared to actually smoking, thus serving as a healthy adjunct to smoking cessation and overall health. Skill acquisition and expertise mediates the relative age effect in sport Ford, Paul R.; Andrew Webster, A. Mark Williams; Liverpool John Moores University The relative age effect has been shown at all levels of sport, including the professional levels of soccer (Edgar & O’ Donoghue, 2004; basketball, Côté et al., 2006; hockey, Baker & Logan, 2007; baseball, Thompson et al., 1991; and Australian rules football, Abernethy & Farrow, 2005). However, researchers have recently provided evidence to suggest that relatively younger athletes (i.e., those born later in the selection year) are sometimes able to mediate, and even reverse, this effect. These athletes have been shown to be more likely to receive higher salaries in professional soccer (Ashworth & Heyndels, 2007) and to be chosen in
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the earlier rounds of NHL drafts (Baker & Logan, 2007) compared to their relatively older counterparts. Athletes who receive higher salaries and are early draft picks tend to be the more skilled performers in their sport. We hypothesized that birth dates for the most skilled performers in professional sports would not demonstrate a relative age effect. The birth dates of 180 professional athletes who were voted the most valuable players including rookie and defensive player of the year in their sport across each season between 1987 and 2007 were analyzed. Five sports were examined, namely, FIFA/UEFA soccer, NBA basketball, NHL hockey, MLB baseball, and AFL football. The birth dates were normalized so that they were categorized into birth quartiles based on each sport’s calendar year in the country where the athletes spent their developmental years up to 18 years old. Chi-square tests were conducted on the quartile birth date data using the assumption of even distribution of births across each quarter of the year. There was no bias towards athletes being born in a particular quartile of the year, χ2 = 2.21, p = .53; their birth dates did not differ in distribution across the four quartiles (Q1 = 21%, Q2 = 25%, Q3 = 29%, Q4 = 25%). It appears that athlete expertise and exceptional skill level can mediate the relative age effect. Findings have implications for talent development. The influence of social evaluation on state anxiety, fear, and static and dynamic balance tasks Geh, Carolyn L.M.; Mark G. Carpenter, Karen Slater, Mark R Beauchamp, Peter R.E. Crocker; University of British Columbia This study investigated the influence of social evaluation on emotional states and static and dynamic balance tasks in nineteen young healthy female adults. In a repeated measures design, social anxiety was manipulated through the use of an expert evaluator. In the experimental condition, participants were told that their performance on a series of balance tasks would be carefully evaluated by an expert on balance for clinical purposes. In the control condition, participants performed the balance tasks without an evaluator present. The test protocol consisted of a set of stance-related and dynamic tasks that were modified and adapted from the Berg Balance Scale. During dynamic tasks, trunk angular displacement and velocity was recorded in the roll and pitch planes using angular velocity transducers (Swaystar, BII, Basel). Ground reaction forces and moments were recorded for all stancerelated tasks to calculate changes in the frequency and amplitude of COP displacements in the anterior-posterior and medial-lateral directions. Measures of trait social anxiety and changes in perceived state anxiety and fear were also recorded across both conditions. There was a significant increase in perceived state anxiety, t(18) = 2.67, p < .05, and fear scores, t(18) = 3.33, p < .01, when participants performed the balance tasks in the experimental condition. When an evaluator was present, significantly higher trunk velocity was observed in the pitch direction while retrieving an object from the floor, and in the roll direction when walking over barriers. These results did not reflect changes observed in the frequency and amplitude of COP displacements with previous studies that manipulated height or emotional picture viewing as a source of perceived anxiety. Two possible explanations for the current findings are considered and directions for future research are discussed. The trilogy of talent: Toward an integrated model of expert performance in sport Grevlos, Mike C.; University of Sioux Falls
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It is now well established that years of deliberate practice and other domain-relevant training activities are necessary for the acquisition of expert performance in sport. It is also agreed upon that high levels of motivation are critical for athletes to commit to and engage in requisite amounts of focused training. Furthermore, it is well accepted that various cognitive mechanisms mediate increasingly advanced performance in sport. Currently lacking, however, is a coherent model of sport expertise that integrates the experiential, cognitive, and motivational factors that can account for exceptional levels of skill. In this presentation, a multidisciplinary model of sport expertise is introduced. This model is a hierarchical synthesis of findings from a variety of research perspectives. A major tenet of the model is that motivation and self-regulation form the ultimate foundation of motor learning and sport performance and cannot be functionally separated from cognition and skill acquisition. In addition, it is proposed that domain-relevant experience, motivation, and cognition serve as the trilogy of talent, and it is this trilogy of talent, rather than natural talent, that explains both failure and success in sport and can account for individual differences in learning efficiency and ultimate achievement. The major goal of the presentation is to explicate the ways in which the specific subfactors within the trilogy of talent are related and describe how they interact in complex ways to create skilled performance, physiological/neural adaptations, and increasingly higher levels of talent. Practical implications of the model are also discussed along with recommendations for future research. From novice to expert motor behavior: A process of refinement to achieve a stable goal Haufler, Amy J.; University of Maryland–College Park; Simon R. Goodman, Pennsylvania State University; Jae Shim, Bradley D. Hatfield; University of Maryland Previous work revealed that novice performers exhibited greater complexity (i.e., noisy) in brain activation patterns as compared the experts who revealed relative refinement. The purpose of this study was to extend this work by examining the relationship between cerebral cortical activity and kinematics of motor behavior during a visuomotor aiming task as a function of expertise. The aiming process in novice (n = 14) and expert (n = 14) marksmen was characterized by the distance between the aiming point and target, and the angle between the aiming point velocity and distance, to yield an aiming trajectory over a 4-s period ending with trigger pull. Consistent with expectation, the amplitude of variability of aiming trajectory was greater in the novice group (dependence d(t) with = 0.61 and = 0.72; p < 0.000) implying greater “noise” in the novice motor system. However, contrary to expectation, the pattern of the aiming trajectory was similar in the two groups and characterized by two phases. Accordingly, for both groups the mean distance between the aiming point and the target systematically decreased in Phase 1 (albeit the amplitude of “noise” in novices was greater) whereas Phase 2 was characterized by random movement of the aiming point and triggering. Therefore, the strategies by novice and experts are similar but differentiated by the magnitude of “noise” in both brain and motor effectors. This would imply that, strategically, both groups are trying to execute the same goal but that expertise is characterized by refinement of the common goal. Does body awareness play a role in tasks requiring a high kinesthetic demand? Ives, Jeffrey C.; Nicole C. Englert, Kent Wagoner; Ithaca College
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Body awareness is the type and amount of attention we place on our body and bodily processes, and is thought to influence both health and physical performance. The aim of this study was to examine perceived body awareness and perceived physical competence with actual measures of kinesthetic body awareness and physical performance. Nine males and 21 females were tested over two days following informed consent. Body awareness was assessed by the Body Awareness Questionnaire (BAQ) and the Somatic Symptoms Amplification Scale (SSAS). Perceived physical performance was assessed by the Physical Self-Efficacy Scale (PSES). Actual physical performance was assessed by posture, balance, and jumping performance: standing postural deviation and left/right weight distribution, single leg balance on foam, functional reach, and accuracy in jumping to a criterion target of one-half max jump height. In all tasks except single leg balance, subjects were asked to either predict or interpret their own performance, which required kinesthetic awareness. Thus, actual performance, predicted/perceived performance, and the error between actual and perceived were assessed. The results showed no significant associations between PSES and any of the posture, balance, or jumping measures for either men or women. For the men, a higher body awareness (BAQ) score was strongly correlated with poorer single leg balance and a higher SSAS score was significantly associated with poorer prediction of left-right weight distribution. For the women, a higher SSAS score was significantly correlated with more error in perceived posture, more jumping accuracy error, and more error in predicting functional reach. We conclude that (1) perception of physical competence is not associated with prediction accuracy on novel tasks requiring balance and kinesthetic acuity, (2) body awareness as measured via standard questionnaires is not associated with kinesthetic awareness, and (3) that higher body awareness may be associated with some indicators of poor physical performance or a distorted perception of performance. Verbal persuasion affects balance efficacy in healthy young adults Lamarche, Larkin, University of Toronto; Jennifer L. Huffman, Kinga L. Eliasz, Kimberley L. Gammage, Allan L. Adkin; Brock University This study was designed to manipulate balance efficacy using verbal persuasion in order to investigate its influence on perceived and actual balance in healthy young adults (n = 16). Participants performed a one-leg, eyes-closed balance task for a maximum duration of 60 s and were then randomized to either a high (provided with feedback that performance was within the top 20% for their age and gender) or low (provided with feedback that performance was within the bottom 20% for their age and gender) balance efficacy group, regardless of actual balance. Following the performance feedback, participants completed the same balance task. Participants rated their balance efficacy before each task, and their perceived stability following each task. Stance duration and trunk movements were recorded during each task to provide an estimate of actual balance. The results showed a significant Group × Time interaction for balance efficacy and perceived stability (both p < 0.05). Following the performance feedback, balance efficacy increased for the high group (M = 33.4 SE = 7.5 to M = 55.4 SE = 11.1) but decreased for the low group (M = 33.5 SE = 9.6 to M = 23.3 SE = 7.5), whereas perceived stability increased for the high group (M = 55.6 SE = 7.3 to M = 68.8 SE = 7.1) but decreased for the low group (M = 53.8 SE = 6.8 to M = 41.3 SE = 6.4). The results revealed no significant changes in actual balance. This study suggests that verbal persuasion can be used to successfully manipulate balance efficacy resulting in altered perceptions of stability in healthy young adults. Examining the influence of manipulated
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balance efficacy using verbal persuasion on perceived and actual balance in a research setting may provide novel ways to change balance efficacy in a practical setting. This study was supported by a grant from NSERC and SSHRC. Muscular power synergies during cycling: Activity-related differences and response to intervention in sedentary and active older adults Newstead, Ann H.; Jody L. Jensen, UTA; Thomas Korff, Brunel University This pilot study is designed to more clearly understand the relationship between aging and activity in terms of lower extremity muscle power. Purpose: The purposes were to determine the efficacy of an intervention of muscular power in the sedentary—and lower power producing—older adults after cycling, and the effect of training on timed functional tasks. Methods: A longitudinal, quasi-experimental design was implemented twice per week over an 8-week period. Half of the sedentary group (OASED) performed cycling designed to improve power; active older adults (OAACT) continued with usual activities. Results: Twenty people participated to include OASED (n = 8; age = 68.9 ± 2.8 years) and OAACT (n = 4; age = 66.0 ± 2.2 years); YA (n = 8; mean age = 24.6 ± 3.1 years) were included as a reference group. Demographics were similar for height, weight, and BMI (p > 0.05). Mean peak power were lowest (F = 8.713; p < 0.002; ANOVA) for sedentary older adults (OASED; 6.8 ± 2.7 W/kg), compared with active older adults (OAACT; 9.8 ± 3.6 W/kg) and young adults (YA; 11.8 ± 2.8 W/kg). Similar trends were noted for Timed Functional Tests (e.g., slow to fast: OASED < 0.024). Similar results were found for the Timed tests (10% faster speed overall); Timed Sit to stand (p < 0.017), TUG (p = 0.017); and a trend for TSC (p = 0.065). Conclusion: Our preliminary results suggest that OASED demonstrated improved mean peak power and impact on some power-related timed tests. The oldest participant (74 years) demonstrated the least amount of improvement (3%). Discussion: Intervention programs that impact lower extremity muscular power may directly impact functioning in sedentary older adults. Future studies are planned to quantify activity-related differences in muscular power and muscular synergies or coordination. Funded by: Texas Physical Therapy Research Foundation; APTA, Geriatric Section, Adopt a Doc. Effects of peppermint scent inhalation on appetite control and caloric intake Reed, Alex; Jude Almeida, Ben Wershing, Bryan Raudenbush; Wheeling Jesuit University Previous research indicates that inhalation of certain scents may reduce hunger levels. The present study evaluated hunger levels during peppermint inhalation vs. noninhalation, in addition to actual food consumption and dietary evaluation (e.g., fat intake, caloric intake, vitamin and mineral intake) over a period of 2 weeks. In a within-subjects design, participants completed a peppermint inhalation condition administered every 2 hours and a noninhalation condition. Each condition was performed for 5 days during separate weeks. During the protocol, participant rated their hunger level every 2 hours and completed a food diary listing everything they consumed for the two 5-day periods. Results indicate participants consumed significantly fewer total calories, calories from saturated fat, total fat, and sugar during the peppermint inhalation condition. Participants also rated their hunger level significantly lower during peppermint inhalation. The primary implication of these results is that peppermint scent can be used as an effective adjunct to decrease appetite, decrease hunger cravings, and consume fewer calories, which may lead to weight reduction and greater overall health.
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The self-regulation of feel and its multiple dimensions: Results from a study exploring the performance of medical students and implications for optimal performance in sport Simon, Christopher R.; Natalie Durand-Bush, University of Ottawa A fundamental human capacity is our ability to regulate and control our thoughts and behavior; regulation by the self, not just of the self (Banfield et al., Vohs & Baumeister, cited in Vohs & Baumeister, 2004). Feel is a subjective and dynamic experience comprising multiple components, such as cognitive, physical, emotional, and social (Arcand et al., 2006; Damasio, 1994). The purpose of this multiple-case study was to explore if and how four medical students could reach and maintain optimal performance by learning to become aware of, and regulate, how they feel in their performance environment with respect to its multiple dimensions. Students participated in an individualized, 12-week, feel-based intervention. Results indicate that the students learned to regulate the way they feel in their performance environment, attuning to the emotional, social, cognitive, and physical dimensions of their felt experiences. Each participant reported a positive influence on their medical performance suggesting that medical students may benefit from learning to self-regulate how they feel in their quest for optimal performance as medical professionals. Although research on feel has been conducted within the context of sport (e.g., Callary & Durand-Bush, 2007; Doell et al., 2006; Wolfe & Durand-Bush, 2006), results of this study reveal a possible subjective and dynamic, inter-regulatory connection between the multiple dimensions of feel. This represents an underdeveloped concept in the literature, warranting an empirical return to the context of sport in order to explore further implications for research in self-regulation and optimal sport performance. Action embodiment in perceptual judgments of famous and nonfamous athletes Sinnett, Scott; Nicola J. Hodges, Romeo Chua, Ricky Pak, Alan Kingstone; University of British Columbia If people are shown an image of an action being performed by either the hand or foot (e.g., kicking a soccer ball or hitting a tennis ball), they will perform an action faster if it requires the same effector. Interestingly, this congruency effect was reported to reverse if the action photo involved a famous athlete. Bach and Tipper (2006) suggested that because the observers were comparatively worse than the professional athlete the observers inhibited the congruent response. We tested this idea by looking at hand and foot responses when identifying two famous (David Beckham and Roger Federer) and two nonfamous athletes in soccer and tennis. There were 32 pictures of each athlete; half of which depicted the athlete in action (e.g., kicking), and half out of action (e.g., standing on the field). Sixty participants were randomly allocated to one of four groups where famous or nonfamous athletes were associated with either a foot or hand response. Contrary to Bach and Tipper, there was no evidence that incongruent effector-sport pairings were faster than congruent pairings, irrespective of stimulus skill level or action context. There was a standard positive congruency effect (p = .013), which was particularly strong for foot responses to famous athletes in action scenarios (50 ms congruency effect). Congruency effects were more evident in action than out of action (p = .04). This study demonstrates that action embodiment is a robust finding. There is no evidence for inhibition of a response effector derived from an unfavorable social comparison, suggesting that an embodied facilitatory effect is the general rule.
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Exercise, fitness, and neurocognitive function in older adults: The “selective improvement” and “cardiovascular fitness” hypotheses Smiley-Oyen, Ann L.; Panteleimon Ekkekakis, Kristin A. Lowry, Iowa State University; Sara J. Francois, Washington University in St. Louis; Marian L. Kohut, Iowa State University Although basic research has uncovered biological mechanisms by which exercise could maintain and enhance adult brain health, experimental human studies with older adults have produced equivocal results. Purpose: This randomized clinical trial aimed to investigate the hypotheses that (a) the effects of exercise training on the performance of neurocognitive tasks in older adults is selective, influencing mainly tasks with a substantial executive control component, and (b) that performance in neurocognitive tasks is related to cardiorespiratory fitness. Methods: Fifty-seven older adults (65–79 years) participated in aerobic or strengthand-flexibility exercise training for 10 months. Neurocognitive tasks were selected to reflect a range from little (e.g., simple reaction time) to substantial (i.e., Stroop Word-Color conflict) executive control. Results: Performance in tasks requiring little executive control was unaffected by participating in aerobic exercise. Improvements in Stroop Word-Color task performance were found only for the aerobic exercise group. Cardiorespiratory fitness and changes in fitness were generally unrelated to neurocognitive function. Conclusions: Aerobic exercise in older adults can have a beneficial effect on the performance of speeded tasks that rely heavily on executive control. Improvements in aerobic fitness do not appear to be a prerequisite for this beneficial effect. Body size and efficiency of physical fitness in stunted and nonstunted children 6–11 years old from southern Mexico Tan, Swee Kheng; Republic Polytechnic; Maria E. Pena Reyes, Escuela Nacional de Antropologia e Historia; Robert M. Malina, Tarleton State University Background: Reduced body size of children is generally associated with absolutely lower levels of physical fitness. The poorer performances are generally proportional to the reduced body size, which has been interpreted an adaptation supporting the “small but efficient hypothesis. Purpose: To compare the physical fitness of growth stunted and nonstunted school children from an urban and a rural community with a history of chronic, mild-to-moderate undernutrition in Oaxaca, southern Mexico. Methods: The sample included 572 children: 156 boys and 149 girls 6–8 years, and 118 boys and 149 girls 9–11 years. Stunting was defined as a height z-score below −2.0 using the CDC growth algorithms. The fitness battery included two motor items: 35-yard dash and standing long jump, and four health-related items: distance run, timed sit-ups, sit-and-reach, and sum of right and left grip strength. MANOVA and MANCOVA with age and height as covariates were use for comparisons within sex and age groups. Results: Prevalence of stunting was similar in girls and boys (18% to 25%). As expected, nonstunted children were significantly taller and heavier with a greater BMI than stunted children. Nonstunted children performed better, in general, on all motor fitness components except for the distance run, but only for grip strength were the differences significant. After controlling for age and height, differences in the fitness of stunted and nonstunted children were not significant with two exceptions, sit and reach was better in nonstunted boys 6– years and the distance run was better in stunted girls 9–11 years. Conclusion: Although the physical fitness of growth-stunted children is generally commensurate with their body size, suggesting some degree of efficiency, it should be noted
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that conditions leading to stunted growth, most noticeably marginal nutritional status and high prevalence of parasitic and infectious disease, are themselves unhealthy. Motor fitness is related to cognitive performance in older adults Voelcker-Rehage, Claudia; Ben Godde, Ursula M. Staudinger; Jacobs University Bremen The importance of physical activity for improvement and preservation of cognitive abilities in old age has been repeatedly examined. Less is known, however, about the influence of the overall motor fitness on cognitive performance and its neurophysiological correlates. In this study we analyzed the relationship between older adults’ motor status and their cognitive performance using behavioral tests and functional MRI. Participants (n = 116; 61–79 years) were tested in a modified version of the flanker task with two response conditions (Li et al., 2004; Psychol Sci). Cognitive performance was measured inside and outside a 3T Siemens Headscanner and expressed as a performance index calculated from reaction time and response accuracy. Motor fitness was assessed by using a heterogeneous test battery of 12 motor tests resulting in an overall motor index (cf. Voelcker-Rehage & Willcimzik, 2006; Age Ageing). Results revealed a significant correlation (r = .56) between motor and cognitive performance. Participants with a higher motor index also showed better performance in the flanker task. Particularly, motor balance, fine coordination, and speed showed the highest association with flanker performance. Stepwise multiple regression showed that 35.1% of the total variance in cognitive performance was explained by these factors. In sum, it seems that motor tasks involving the visual system, eye-hand coordination, and speed were related to flanker performance whereas motor tasks involving strength and flexibility were not. For fMRI data analysis, the group was split into participants with low and high motor index, respectively. During the flanker task, low fit subjects with rather good cognitive performance showed wide spread activation patterns indicating compensation processes, whereas high fit older adults had more focused activations. This suggests that a higher motor status might also lead to improved cognitive performance, whereby decision and inhibition processes seem to be more effective. The effects of ACL surgery and rehabilitation on force variability Voudrie, Stefani J.; Kyle T. Ebersole, Jacob J. Sosnoff; University of Illinois at UrbanaChampaign Damage to the anterior cruciate ligament (ACL) is one of the most common knee injuries in sports. The goal of rehabilitation following ACL injury is to return the patient to normal neuromuscular function. Yet, following rehabilitation, a decrease in maximal strength output between involved and uninvolved limbs frequently persists. Although maximal muscular strength is an important clinical marker, most activities of daily living are carried out at submaximal force levels. The actual effects of the ACL surgery and rehabilitation process on force variability are unknown. The purpose of this investigation was to examine differences in submaximal force control between the involved and uninvolved limb following injury, surgery, and rehabilitation. In order to address this research question, four young subjects who were at least 6 months post-op performed submaximal force production with their involved and uninvolved limb. They were seated on the Humac Isokinetic Dynamometer with each leg positioned for leg extension testing according to manufacturer’s guidelines. The subjects performed submaximal force production on both legs at leg flexion angles of 15°, 30°, and 60° below the horizontal plane at 15%, 30%, and 45% of their maximal force
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production. Three 20-s trials were conducted at each joint angle–force combination. The mean, standard deviation, coefficient of variation, and approximate entropy (ApEn) of the force output was calculated. The involved leg was found to be significantly weaker than the uninvolved leg. There was no significant difference in the amount of force variability (i.e., SD and CV between legs). The uninvolved leg had increased structure of force variability (i.e., ApEn). Overall, the findings indicate that there is a difference in submaximal force control following ACL injury and rehabilitation. The actual mechanisms driving the limb differences remain to be elucidated. Constituent year and youth ice hockey injury: A new consideration for models of psychological vulnerability and response to sport injury Wattie, Nick; Stephen P. Cobley, Leeds Metropolitan University; Alison Macpherson, York University; Jim McKenna, Leeds Metropolitan University; William J. Montelpare, Lakehead University; Joseph Baker, York University Although numerous variables have been discussed in sport injury psychology, research has yet to consider the possible influence of athletes’ “constituent year.” Constituent year describes an athletes’ year of participation within multiple-year age bands. For example, in Canadian youth ice hockey children aged 10 participate in the Atom age band for 2 years (i.e., in two different constituent years) before progressing to the next age band at age 12. The purpose of this study was to examine the relationship between constituent year and injury risk in Canadian youth ice hockey. Study 1 was based on data from the Canadian Hospitals Injury Reporting Prevention Program, and compared injury proportions according to constituent year among injured Atom (n = 830), Peewee (12–13 years, n = 1,738), and Bantam (14–15 years, n = 2,168) players. A greater proportion of injured Atom (62.5% vs. 37.5%, χ2 = 52.12, p < .0001) and Peewee (54.9% vs. 45.1%, χ2 = 16.62, p < .0001) players were second-year constituent players. In Study 2, the constituent year of injured Peewee (n = 1996) and Bantam (n = 2963) players were compared using data from Hockey Canada’s Insurance Database, which included competition level as a variable of interest. At the highest levels of competitive play, a greater proportion of injured Peewee (65.4% vs. 34.6%, χ2 = 11.97, p = .001) and Bantam (57.5% vs. 42.5%, χ2 = 11.27, p = .001) players were in Constituent Year 2. First-constituent-year players comprised a greater proportion of injuries in the lowest levels of competitiveness, house leagues (χ2 range = 12.05–18.79, p = .001). These results suggest that injury risk differs based on athletes’ constituent year of participation within an age group, which is moderated by level of competition. Considering these findings through a model of sport injury psychology (Wiese-Bjornstal, 2004), and neuro-developmental sport readiness (Patel, Pratt, & Greydanus, 2002) as a basis, the relevance of these findings are discussed in regard to talent development, coaching practices, and psychosocial vulnerability to sport injury.
Journal of Sport & Exercise Psychology, 2008, 30(Suppl.), S38-S60 © 2008 Human Kinetics, Inc.
Motor Development* Neonatal stepping on a visual treadmill: Reactions to approaching and receding optic flows Anderson, David I., San Francisco State University; Marianne Barbu-Roth, University of Paris, Descartes, and CNRS; Ryan Streeter, Robert C. Schleihauf; San Francisco State University; Joëlle Provasi; EPHE The purpose of the current experiment was to extend our recent discovery that neonatal air stepping can be induced by an approaching optic flow, independent of the tactile stimulation thought necessary to release the upright stepping pattern. The primary question was whether air stepping could be induced by both approaching and receding optic flows. Twetny-four 3-day-old infants were held in an upright position above a table, the surface of which was a solid rear projection screen, and exposed for 1 min to either (1) an optic flow that moved toward the infant (Toward), (2) an optic flow that moved away from the infant (Away), (3) a static pattern (Static), or (4) stepping on a table surface in the absence of optic flow (Tactile). The visual stimuli consisted of a pattern of black circles on a white background (spatial frequency = .33) projected onto the table surface at a linear velocity of .17 m/sec (optical velocity = 23 deg/sec). Data from two video cameras were later reduced and analyzed using custom kinematic analysis software. Planned comparisons indicated significantly more stepping in the Toward condition than in the Static condition, a result that replicated our previous findings. The Away condition was intermediate to the other two air stepping conditions and not significantly different from either one. The Tactile condition led to significantly more stepping than the Static condition, but not the Toward or Away conditions. Preliminary analyses of the kinematic data have revealed a significant reduction in the range of knee joint motion in the Away condition relative to the Toward condition and there is evidence for qualitative differences in the trajectory of the ankle through the step cycles. The latter finding suggests that the ankle tends to move in a clockwise direction in the Toward condition and in a counterclockwise direction in the away condition. The current findings suggest that visually induced neonatal stepping is a robust phenomenon and the kinematic data hint that the coupling between vision and stepping might actually be quite sophisticated. Intention and visual stimulus velocity effects on elderly postural control Barela, Jose A.; Milena Razuk, Alexandre K. Prado, Andrei G. Lopes, University of Sao Paulo State The goal of this study was to verify the effects of intention and visual surrounding manipulation with different velocities in the coupling between visual information and body oscillation in elderly adults. Twenty healthy and active elderly adults were divided in two groups and *The abstracts are alphabetically arranged by the first author’s surname within each of the four sections—Interdisciplinary, Motor Development, Motor Learning and Control, and Sport and Exercise Psychology.
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asked to stand inside a moving room which oscillated at 0.2 Hz. For one group, the moving room oscillated with a 0.5 cm amplitude and 0.6 cm/s peak velocity (low velocity group, LV), whereas for the other group, the moving room oscillated with a 0.9 cm amplitude and 1 cm/s peak velocity (high velocity group, HV). Each group participated in six trials of 60 s with the moving visual room, preceded by a single trial with a stationary visual room. In the first three moving trials, participants were instructed to look straight ahead and they were not aware that the room was moving (normal condition). In the last three trials, participants were informed that the room was moving and were instructed to resist its influence (resist condition). Gain, phase, spectrum frequency sway amplitude (SFSA) and mean sway amplitude (MSA) were calculated. The results showed that body sway was induced by the visual stimulus but it was dependent on intention and stimulus characteristic. Gain was higher in the LV than in the HV group and in the normal than resist condition. SFSA was higher in the normal than in the resist condition but not different between the groups. No temporal difference between the room and body sway was observed. Finally, MSA indicated that when the room oscillated, body sway was larger than when the room was stationary. However, no difference was observed between normal and resist condition. These results indicated that elderly adults can intentionally resist the influence of the visual stimulus even though they still sway more than when there is no manipulation of the visual surroundings. Finally, elderly adults show adaptive changes in sensory influences when the stimulus characteristic is changed. Predicting performance on selected motor skills of females: A multilevel analysis Branta, Crystal; Teri Hepler, Kyle Morrison, Joe Eisenmann, Vern Seefeldt, John Haubenstricker; Michigan State University Growth and maturation impact skill performance. Biological maturity status and adiposity have been documented to affect motor performance, especially during adolescence. The purpose of this study was to determine (a) the influence that body mass index (BMI) and skinfolds have on individual performance and (b) the impact of maturity group (determined by age at peak height velocity; APHV) on performance of the vertical jump (VJ), horizontal jump (HJ), and flexed arm hang (FAH) of females measured longitudinally from ages 6 through 16 years. Participants (n = 141) were measured semiannually on standing height, weight, three skinfolds (SS), VJ, HJ, and FAH. Annual height velocities were calculated and then analyzed using GraphPad Prism software to determine APHV. The APHV was used to sort maturity groups. Early maturers (EM) (n = 26) showed APHV < 11.5 years; average maturers (AM) (n = 68) were designated as 11.5 years. < AHPV < 12.5 years; and late maturers (LM) (n = 47) had APHV > 12.5 years. Mean APHV was 12.1 ± 0.9 years. Statistical analyses were conducted using multilevel modeling. BMI and SS were entered as control variables at Level 1, the within-person analysis; SS was negatively related to performance on all three skills; BMI was negatively related to performance on FAH. In order to test polynomial growth functions, age was centered at age 11. Results of the Level 2 across subjects analyses showed that maturity group did not predict performance at age 11 on any skill; thus it is not the control parameter early in adolescence. However, for FAH, AM had a significantly higher instantaneous rate of change than did LM; i.e., AM were increasing their FAH performance at a greater rate than were the LM group. On VJ, the performance of LM did not decrease as fast as AM at age 11. For the HJ, LM exhibited a significantly greater rate of change than did EM; i.e., LM were increasing their HJ performance more than
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the EM. Maturity influences performance in this sample beyond that of BMI and skinfolds alone; specific effects at various ages are yet to be determined. Does perceived motor ability influence perceived reachability in children? Caçola, Priscila M.; Carl P. Gabbard, Alberto Cordova; Texas A&M University Motor imagery has been cited as an action representation of planned movements. One form of action representation of developmental interest is reach estimation—the perceptual cognitive judgment of whether an object is within or out of reach. A common observation especially among young children is overestimation, which speculatively, has been linked to perceived motor ability (PMA) associated with overconfidence. The idea that level of PMA may be an influencing factor in perceived reachability is not a new idea, even though little information is available on the relation. We have suggested on several occasions that perceived reach might be based in large part on one’s perceived ability and perceived task demands. The present study examined the possible influence of PMA using two age-appropriate versions of the Harter Scales in estimating reachability among 42 children representing age groups 7, 9, and 11 years. Concerning reach, chi-square results indicated no age difference in total error; however, for all groups significantly more error was displayed in extrapersonal out of actual reach compared to peripersonal space within reach. For PMA, ANOVA and post hoc results revealed a significant difference between the three groups; the 7-year-olds’ scores were higher than the two older age groups. Relationship analysis revealed a weak but significant correlation between perceived reachability and PMA, but not for age. In addition, regression analysis identified PMA to be the only variable that significantly predicted perceived reachability. In general, these results support previous findings suggesting that younger children are typically overconfident about their abilities resulting in inflated self-evaluative judgments. Although we do not rule out a possible “confidence effect” (all groups overestimated), it appears that a general assessment of PMA is not a strong predictor of motor behavior among children in the context of the task used here. Walking patterns in infants at moderate risk for neuromotor disabilities with or without treadmill training Chen, Li-Chiou; Julia Looper, Heather Neary, Dale Ulrich, Rosa Angulo-Barroso; University of Michigan Complications during the perinatal period may result in either transient neuromotor disabilities or ultimately a diagnosis of cerebral palsy (CP). Infants at risk for neuromotor disabilities often show abnormal muscle tone and motor development delays during the first 2 years. Previous research showed that treadmill (TM) training is beneficial in improving gait performance in children with CP. The purpose of this study was to investigate gait performance in infants at moderate risk for neuromotor disabilities (mod-risk) with or without early TM training. Twenty mod-risk infants were randomly assigned to either a control (C) or an experimental (TM) group. Infants entered into the study when they were able to take 10 steps on the treadmill in 1 min and thereafter were followed monthly to assess stepping performance on the treadmill until the onset of independent walking. During the intervention period, infants in the TM group received home-based treadmill training for 8 min/day, 5 days/week. Once the child could independently walk for 8–10 continuous steps, his/her gait was examined and reevaluated again 3 and 6 months later. Children’s footprints were recorded via a GaitRite mat to calculate the spatiotemporal gait parameters. The results
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showed that both groups attained independent walking at comparable corrected ages (C: 14.3 ± 2.5; TM: 13.7 ± 2.2 months) with similar spatiotemporal parameters (all p > 0.05). With more walking experience, mod-risk infants increased their step length, velocity, and cadence, and decreased the step width (all p < 0.05). Similar to typically developing infants, mod-risk infants decreased their step length variability but increased step width variability after gaining more walking experience (both p < 0.05). Our results suggest that a relatively short TM training protocol does not seem to provide the same benefits to mod-risk infants as it did to infants with Down syndrome. Infants showing transient neuromotor disorders achieved comparable walking behavior than typically developing peers although a few months later. Does perceived postural constraint affect reach estimation?: A developmental view Cordova, Alberto; Carl P. Gabbard, Sunghan Lee; Texas A&M University Estimation of whether an object is reachable or not from a specific body position constitutes an important aspect in effective motor planning. Studies of estimating reachability via motor imagery with adults consistently report the tendency to overestimate, with some evidence of a postural effect (postural stability hypothesis). This idea suggests that perceived reaching limit depends upon one’s perceived postural constraints. In other words, with greater postural demands, one elects to program a more conservative strategy. We tested this idea among children 7, 9, and 11 years of age by asking them to estimate using motor imagery, whether an object (target) was within or out of reach while seated (Reach1) and in the more demanding posture of standing on one foot and leaning forward (Reach2). Target presentation was given in random order with five trials at each of the seven targets presented in peripersonal (within reach) and extrapersonal space (beyond maximum reach); conditions were counterbalanced between participants. Based on published work with adults, we expected a significant postural effect with the Reach2 condition as evidenced by reduced overestimation. Furthermore, we hypothesized that the postural effect would be greater in younger children. Chi-square analysis for frequency data and ANOVA procedures for mean bias determination indicated no age or condition difference, therefore providing no support for a postural effect. Interestingly, when the data was compared to that reported for adults (using a similar paradigm), a developmental difference emerged. That is, adults recognized the perceived postural constraint of the standing position resulting in under- rather than overestimation as displayed in the seated condition. Possible explanations include overconfidence in the children and developmental differences associated with use of visual information and the ability to map egocentric coordinates. In any case, these preliminary data suggest that adultlike judgments of perceived reachability continue to be refined through adolescence. Aging effect on postural responses following forward platform perturbation de Freitas, Paulo B.; University of Delaware; Jose A. Barela, Sao Paulo State University at Rio Claro The ability to minimize horizontal displacements of the center of mass (CM) after an unexpected perturbation is crucial to prevent falls and depends on how quickly muscles are activated, reach the maximum level of activation, and produce torque. It is known that older adults (60 years old or older) exhibit neuromuscular changes that affect their ability to respond to balance perturbations. However, it is still unknown whether these changes are limited to older adults or occur in earlier ages. The aim of the study was to examine aging effects on
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EMG and kinematic patterns after balance perturbations. Thirty-six volunteers, divided into four groups (young [YA, 20–25 years old], middle age [MA40–45 and MA50–55], and old [OA, 60–65 years old]), stood on a platform that could be either kept stationary or moved back or forward. EMG onset, time to peak, and amplitude (IEMG) of agonist muscles (TA and RF), and maximum CM backward displacement and time to CM reversal were assessed after forward movement of the platform (3.6 cm, 0.4 s). Also, PCA was performed to assess postural synergies used after the perturbation. The results showed that YA activate TA and RF earlier than OA and reach the peak of activation earlier than MA50-55 and OA. However, no differences among groups in IEMG, in maximal CM displacement, and time to CM reversal were observed. These results indicated that changes in temporal pattern of muscle activation are already displayed by persons after 50 years old but they are still able to fully activate their muscles and avoid additional CM displacement as younger adults. In addition, PCA showed the use of similar postural synergy among groups. Taking these results together, we conclude that changes in temporal activation patterns of the muscles involved in responses to perturbations can be seen in individuals younger than 60 years of age. However, such changes have no effect on the CM displacement and time to reversal, which would suggest that temporal aspects of muscle activation could play minor role in controlling CM displacement after moderate postural perturbations. The development of discrete and cyclical actions in children Dean, Noah J.; Wondae Kim, John J. Buchanan, Carl Gabbard; Texas A&M University From a developmental perspective, a fascinating aspect of human motor behavior is the emergence of functional action sequences involving the upper limbs. The intent of the present study was to identify the developmental time course of the motor control processes that affect change in the ability to integrate and switch between discrete and cyclical motor primitives in order to produce task specific functional action sequences. Children representing ages 5, 7, 9, and 11 years performed a series of rapid aiming tasks designed to compare the assembly of functional action sequences from cyclical and discrete motor primitives. Index of difficulty (ID) was manipulated via two targets of varying widths equal and mixed. Data were collected via infrared light-emitting diodes recorded with a 3-D motion analysis system Optotrak 3020 camera. Results indicated that for all age groups with targets of equal width: harmonic motion emerged in the low ID 2.85 condition and inharmonic motion in the high ID 5.85 condition, with MTs longer in the high ID compared to the low ID condition, and with less time accelerating the limb in the high ID compared to the low ID condition. In the mixed width condition, 5-year-old’s movement harmonicity (H) values when moving to the low ID and high ID targets were equal, indicating discrete actions. In the 7- to 11-year-olds, a separation between the values of H for the mixed targets started to emerge, similar to and yet still different from adult data in the same mixed target condition. All the children were better than 90% accurate when moving to the low ID target. When moving to the high ID target in the mixed target width condition, accuracy increased with age. These preliminary data suggest that the processes necessary for integrating discrete and cyclical primitives starts to emerge between 9 and 11 years of age. This finding is consistent with research that supports the emergence of improved planning processes between the ages of 8 and 10 and improved processing capacity that increases significantly from age 7 on.
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Entropy based assessments of developmental delay in infants learning to sit Deffeyes, Joan E.; University of Nebraska at Omaha; Regina T. Harbourne, University of Nebraska Medical Center; Anastatia Kyvelidou, University of Nebraska at Omaha; Wayne A. Stuberg, University of Nebraska Medical Center; Nicholas Stergiou, University of Nebraska at Omaha and University of Nebraska Medical Center Upright sitting is an important early motor milestone in infant development. Analysis of sitting posture gives insight into the developing motor control system of the infant early in development when intervention may be most effective. Entropy measures, which quantify the complexity of the postural sway, are well suited to explore the subtleties of postural sway data, giving insight into pathologic motor control functioning. In this study, developmental delay of motor control function in infants was assessed by analysis of sitting postural sway data acquired from force plate center of pressure measurements. Three entropy measures were used, approximate entropy, symbolic entropy, and a newly developed measure, asymmetric entropy. For each method of analysis, parameters were adjusted to optimize the separation of the results from the infants with delayed development from infants with typical development. The method that gave the widest separation between the populations was the asymmetric entropy method, which we developed by modification of the symbolic entropy algorithm. The approximate entropy algorithm also performed well, using parameters optimized for infant sitting data. The infants with delayed development were found to have less complex patterns of postural sway in the medial-lateral direction, and were found to have different left-right symmetry in their postural sway, as compared to typically developing infants. The asymmetry in infant sitting posture was detected only by the newly developed asymmetric entropy measure. This work was supported by NIH (K25HD047194), NIDRR (H133G040118), and the Nebraska Research Initiative. Is lower motor skill level in obese children just a matter of mass? D’Hondt, Eva M.G.; Benedicte I. Deforche, Ilse M. De Bourdeaudhuij, Matthieu E.M. Lenoir; Ghent University Prevalence levels of overweight and obesity are rapidly increasing. To date, only a limited number of studies has investigated what effects excess body mass has on children’s motor skill performance. The present indications for an inverse relationship between motor skill and body weight are mainly restricted to gross motor skills, like postural balance and gait (McGraw et al., 2000). The observed differences are primarily explained from a mechanical point of view, because excess body mass and the accompanying body geometry might affect motor control and coordination. Since evidence is too limited and detailed information about fine motor skills is lacking, alternative explanations cannot be excluded at this time. In the present study, we wanted to examine if childhood obesity imposes constraints on manual dexterity by means of a peg placing task with varying demands on the postural system. Participants (normal-weight, overweight, and obese children, age 5–12 years) performed the task at study while seated and while standing with both feet on a 4.5-cm-wide balance beam. By challenging fine motor control as well as balance control in the latter condition, one could expect significant group differences because it has been shown that in children a well-controlled postural balance is beneficial for goal-directed movements (Berrigan et
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al., 2006). Observing differences between weight categories in the sitting condition would suggest that an underlying perceptual-motor deficit in obese could also be responsible for their lower fine motor skill level. Our results are thus discussed in order to elucidate the relative contribution of excess body mass and a possible perceptual-motor deficit to the lower motor skill level in obese children. Practice effects on isometric force/torque production in children with developmental coordination disorder Diz, Maria Angelica R.; Universidade Estadual Paulista; Cynthia Y. Hiraga, Universidade de São Paulo; Ana M. Pellegrini, Universidade Estadual Paulista Finger force production is essential for innumerable daily activities. Previous research has shown that children with developmental coordination disorder (DCD) exhibit more difficulties than typically developing (TD) children in manipulative tasks involving isometric force contraction. The present study examined the effect of practice in the performance of an isometric force/torque task in children with DCD and TD children. Twelve children with DCD (mean age 10.1 years, SD ± 0.49 year) and 12 TD (mean age 10.0 years, SD ± 0.55 year) children were asked to practice, with visual feedback, a constant isometric force/torque task (at 25% of the maximum voluntary contraction) with the thumb and index finger. Practice sessions consisted of 15 trials that were administered during five consecutive days. The results revealed that TD children were consistently more accurate to produce the required isometric force/torque contraction than children with DCD over 5 days of practice (p < .05). Children in both groups improved accuracy over practice sessions (p < .001). Specifically, a substantial improvement in accuracy was displayed by children with DCD from the third to the fifth day of practice. With respect to variability measure, the results showed that children with DCD gradually diminished variability of the constant force/torque production over practice days (p < .01), whereas TD children did not show such differences over practice days. The findings of the present study indicated that children with DCD are capable of improving the performance of a task involving a specific demand. Seeing the wrong arm: The effects of a mismatch between visual and proprioceptive information on bimanual coordination in typically developed children Feltham, Max G.; Manchester Metropolitan University; Annick Ledebt, VU University Amsterdam; Martine H.G. Verheul, University of Edinburgh; Geert J.P. Savelsbergh, VU University Amsterdam The aim of our research was to investigate how a mismatch between visual and proprioceptive information affects the stability of arm movements during bimanual coordination in children from different age groups. Participants performed a symmetrical circular bimanual task with visual information available from both arms (transparent glass condition), one arm opaque (screen condition), and one arm and its mirror reflection (mirror condition). The mirror in the latter condition created the illusion of a zero lag symmetrical movement between the upper limbs. Movement of both wrists were measured to quantify the interlimb temporal relation CRP and its variability between the hands SD CRP and to assess the degree of intralimb stability jerk. The results showed that younger children could maintain a similar temporal coupling between the arms but their movements were more variable compared to the older group. Moreover, in the mirror and glass, all participants’ arm movements were significantly less variable compared to the screen condition. Additionally, there were no differences for jerk
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between the groups or divides. The results suggest that the perceived zero lag visual information facilitated the symmetrical circular bimanual movement compared to the opaque screen condition and was equivalent to the glass condition. The possible underlying mechanism for the acute changes in kinematics is the redirection of attention towards the more impaired hand through positive reinforced visual feedback from the mirror reflection. The “mirror box”: Effects on bimanual coordination in typically developed children and children with spastic hemiplegic cerebral palsy Feltham, Max G.; Manchester Metropolitan University; Annick Ledebt, VU University Amsterdam; Simon J. Bennett, Liverpool John Moores University; Martine H.G. Verheul, University of Edinburgh; Geert J.P. Savelsbergh, VU University Amsterdam The mirror box creates a visual illusion, which gives rise to a visual perception of a zero lag symmetric movement between the less and more affected arms. The aim of the experiment is to examine whether the mirror box might help to facilitate the functionality of the more affected hand of children with spastic hemiparetic cerebral palsy (SHCP). Participants (n = 9) between 6–18 years old with SHCP and a typically developed age-matched control group (n = 15) performed a symmetrical circular bimanual task with visual information available from both arms transparent (glass condition), one arm opaque (screen condition) and one arm and its mirror reflection (mirror condition). The mirror in the latter condition created the illusion of a zero lag symmetrical movement between the upper limbs. Movement of both wrists were measured to quantify the interlimb temporal relation CRP and its variability between the arms SD CRP and to assess the degree of intralimb stability jerk. It was found that children with SHCP were able to maintain a similar mean temporal coordination between the arms but their movement was more variable compared to their typically developed peers. In general the variability of the participants’ arm movements was significantly greater in the opaque screen condition compared to the glass and mirror condition, which did not differ from each over. The amount of intralimb stability increased for children with SHCP in both their arms during the mirror condition. The results suggest that the perceived zero lag visual information facilitated a reduction in jerk during the symmetrical circular bimanual movement compared to the opaque screen condition and was equivalent to the glass condition. The possible underlying mechanism for the acute changes in kinematics is the redirection of attention towards the more impaired arm through positive reinforced visual feedback from the mirror reflection. Changes in critical elements of striking a ball as a result of motor intervention in disadvantaged preschoolers Goodway, Jacqueline D.; Irmak Hurmeric, Ohio State University; Leah E. Robinson, Auburn University; Jessica Stevens, Robin Dunn; Ohio State University Striking a ball with a bat is a common fundamental motor skill taught during the early childhood years, but little empirical evidence exists to guide the instructional process. This study examined the effects of striking instruction in young children. Participants (N = 122) consisted of disadvantaged preschool children (M = 54 mo) in a motor instruction (MI, n = 65) and comparison (C, n = 57) group. All participants were evaluated striking a ball off a tee using the striking criteria (0–10 points) from the Test of Gross Motor Development–2 (Ulrich, 2000) before and after the instructional period. The MI group received 12 10-min sessions of striking instruction as part of a 12-week 1,080-min motor skill program. A developmental
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task analysis of striking was developed and used to guide striking instruction. An ANOVA with repeated measures found a significant Group × Time interaction, F(1, 118) = 220.69, p < .001, ES = .65, but no significant Group × Time × Sex interaction (p = .40). Overall, the MI group had better striking skills than the C group from pre- to posttest. In order to examine what critical elements changed over time, chi-square analyses assessed differences between the MI and C groups in the distribution of scores for the striking critical elements. As predicted, at the pretest there were no significant differences in the distribution of scores for the five critical elements of striking between groups. However, at the posttest there were significant differences between the MI and C group for the distribution of scores for 4 of the 5 following critical elements: grip (p ≤ .001), sideways orientation with feet parallel (p ≤ .001), weight transfer to front foot (p ≤ .001), and contacts ball (p ≤ .001). There were little changes in hip and shoulder rotation for both groups. Overall, striking skills improved as a result of 120 min of instruction and the MI group was significantly different from the C group in the distribution of scores for 4 of the 5 poststriking critical elements. These data have implications to teaching striking to young disadvantaged children. The effect of stochastic noise to improve sitting postural control in infants with moderate to severe cerebral palsy Harbourne, Regina T.; University of Nebraska Medical Center; Anastasia Kyvelidou, Joan E. Deffeyes, Nicholas Stergiou; University of Nebraska at Omaha Children with moderate or severe cerebral palsy (CP) have significant difficulty maintaining dynamic sitting postural control. Because postural control is at the root of attention, exploration, and perception during development, dynamic control of sitting is a critical skill for learning. The purpose of this preliminary research work was to determine whether a combination of a perceptual-motor treatment and surface stochastic noise could make short-term changes in sitting postural control. Perceptual-motor treatment has been shown to improve postural control measures in sitting over time. Stochastic noise has been shown to improve postural control measures in standing in adults with postural control deficits. Two 2-year-old children with CP who had emerging sitting skills were measured before and after a 20-min treatment session. One child had a diagnosis of spastic quadriplegia, GMFCS level IV, and the other child had a diagnosis of athetosis, GMFCS level III. Stochastic noise through nonperceptible vibration of the sitting surface was provided during dynamic sitting activities using a perceptual-motor approach. Center of pressure (COP) data was acquired immediately before and after treatment. The COP data were analyzed using measures of the amount of variability, i.e., root mean square, and range for both the anterior/posterior and medial/lateral direction. We also calculated the largest Lyapunov exponent and approximate entropy for both directions, which are nonlinear measures that quantify the complexity of the COP time series. These before and after measures were compared to a typically developing infant at the same stage of sitting (prop sitting). Both children with cerebral palsy showed changes in the COP values toward those of the typical infant, as well as increasing the length of sitting time. These results indicate that the use of stochastic noise at the sitting surface added to perceptual-motor treatment can possibly improve sitting postural control in children with CP in the short term, and should be further investigated for long-term effects. Fundamental motor skills development: The effect of a preschool physical education curriculum and children’s engagement in skill-specific practice Iivonen, Susanna; University of Jyvaskyla
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The present study investigates the effect of a preschool physical education curriculum (PEC) on 4- to 5-year-old Finnish children’s fundamental motor skills (FMS) and observes children’s engagement in skill-specific practice on organized PEC lessons. During 6 months, the experiment group (n = 39, mean age 56 ± 7 months) participated in 48 × 45-min PEC lessons. At the same time, the control group (n = 45, mean age 55 ± 7 months) participated in normal preschool PE, consisting of 24 × 60-min lessons. The APM-Inventory (Numminen 1995), tested to be a reliable method for Finnish children, was used for measuring static balance, dynamic balance, running speed, standing broad jump, and a sum variable of three manipulative skills. Four measurements were made: baseline, after PEC lessons 1–24, after PEC lessons 25–48, and 3 months after. Four children of the experiment group were objectively measured with General Observation Software (2007), which provided a measurement of time in seconds spent practicing eight motor skills and in sedentary behavior. The software summarized the percentage of total time during which the nine categories were observed. To produce reliable observation category scores, 81–100% interobserver agreement of two trained observers was demonstrated. The results showed that the PEC affected the girls static balance (p = 0.03) and standing broad jump (p = 0.05), and the boys running speed (p = 0.02). No effects on dynamic balance or manipulative skills were seen. In the observed children’s mean results, 49.1% of the time on the PEC lessons was spent in sedentary behavior. The skill-specific practice percentages were walking and running (17.7), upper limb manipulation (15.9), jumping activities (6.7), whole body manipulation (4.7), walking on all fours and crawling (3.5), one foot balancing (0.9), lower limb manipulation (0.9) and body rolling (0.6). The PEC had limited positive influence on children’s FMS. Observation results may suggest that there was not enough skill-specific practice in the PEC for the experiment group to outperform the control group in all measured FMS. Relationship between fundamental movement skill and sport skill level of young adults Kearney, Philip; Patrick J. Smyth, Ross Anderson; University of Limerick A lack of skill has been suggested as a contributing factor to non-participation in sport (Clark, 1995). An underlying concept in physical education is that fundamental movement skills may aid in the development of related sport skills (Gallahue & Ozmun, 2002). The purpose of this study was to investigate the throwing ability of a population of young adult university students, and to determine the relationship between this fundamental skill level and performance on a related sport skill. Fifty-four first-year university students (26 female and 28 males, mean age 19.54 years) threw for maximum speed and performed volleyball overhead serves. A radar gun and video camera were used to record outcome and performance. Serve outcome was assessed as the ability to consistently serve into the opposite court. Results indicated that both male (overbar x = 24.9 m/s) and female (overbar x = 15.0 m/s) participants performed at a poor level relative to that reported in the literature (Leme & Shambes, 1978; Ehl et al., 2005). Analysis of form scores classified three participants (male) as proficient, with 13 further participants classified as approaching proficient (12 male). Significant gender differences were revealed for backswing (2, N = 54, χ2 = 16.90, V = 0.559), step (1, N = 54, χ2 = 6.23, V = 0.34), humerus (1, N = 54, χ2 = 4.969, V = 0.303), and forearm (1, N = 54, χ2 = 9.797, V = 0.426). Expected values were too low to calculate χ2 for trunk; however, a gender bias was evident with 9/28 males and 0/26 females demonstrating differentiated rotation. Volleyball serve outcome was found to be significantly related to throwing level (1, N = 53, χ2 = 7.43, V = 0.37), but caution is urged in interpreting this
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finding owing to the lack of females in the advanced throw categories. This population of young adults showed gross deficiencies in throwing ability, particularly for females. Future research will examine the impact of this poor skill level on the initial form and subsequent learning strategies of the volleyball serve, and explore the mechanism by which fundamental skill level may facilitate sport skill acquisition. Multisensory-motor integration in arm movements of typically developing children King, B.R.; M.M. Pangelinan, O.E. Aluko, F.A. Kagerer, J.E. Clark; University of Maryland College Park Previous research has shown that the adult central nervous system can flexibly re-weight visual and proprioceptive information to provide a more accurate estimate of arm position, a prerequisite for the production of accurate and consistent goal-directed arm movements (van Beers, Sittig, & Gon, 1999). The current study sought to investigate if such a flexible, multisensory-motor integration mechanism exists in children. Two groups of children, 7–8 and 9–11 years old (n = 10 each), and a group of adult participants (n = 9) performed a localization task to one of three types of targets: visual, proprioceptive, or simultaneous visual and proprioceptive (baseline conditions). In order to assess multisensory-motor re-weighting, participants also performed the task when the simultaneous visual and proprioceptive stimuli were incongruent. During baseline, the 7- to 8-year-old children demonstrated smaller variable errors to the visual targets, as compared to the proprioceptive targets, whereas the adults demonstrated smaller variable errors to the proprioceptive targets. Interestingly, during the incongruent condition, both the 7- to 8-year-old children and the adults consistently shifted their end-point localization to the sensory estimate with the smaller variable error, providing evidence for the re-weighting of sensory inputs based on the inverse of the variance of the unimodal estimates (i.e., probabilistic multisensory-motor re-weighting). Conversely, despite demonstrating slightly smaller variable errors during the visual baseline condition, the 9- to 11-year-old children shifted their end-point localization toward the proprioceptive target during the incongruent trials, potentially indicating a transition period in multisensorymotor integration marked by increasing precision of proprioceptive acuity. Future research will attempt to fully characterize the developmental trajectory (i.e., 4- to 14-year-olds) of multisensory-motor integration in both typically developing children and children with movement difficulties. Research supported by NIH RO1HD42527 and NIH RO3HD050372. How children learn to play violin: Motor learning by freezing the right degrees of freedom Konczak, Juergen; Heidi Vander Velden, University of Minnesota; Lukas Jaeger, Eidgenoessische Technische Hochschule Zuerich; Kristen Pickett, University of Minnesota Playing a string instrument requires precise patterns of bimanual coordination that are usually acquired over years of practice. This study investigated the motor learning strategies of novice adults and child violinists. Specifically, we analyzed how changes in joint coordination influenced the precision of bow movements and examined whether joint freezing and the successive release of joint degrees of freedom is a universal, age-independent feature of motor skill acquisition. The performance of 11 children (age range: 4–12 years), three beginning- to advanced-level adult players, and two adult concert violinists were evaluated using a piece of music that all violinists had mastered as their very first violin piece. We found that learning was associated with a reduction of shoulder flexion-extension movements
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in both children and adults, while the remaining mechanical degrees of freedom at elbow and shoulder showed patterns of neither freezing nor freeing. The reduction in sagittal shoulder motion flexion/extension correlated positively, r = 0.71, with the precision of the bow placement on the strings as measured by the angle between the bow and string. The amount of accumulated lifetime practice explained 65% of the bow angle variability and 46% of the variability in the range of shoulder flexion/extension movements, but only 8% of the variability elbow angular amplitude. Our findings demonstrate that learning to play the violin was not associated with a release of joint degrees of freedom, but was characterized by an experience-dependent suppression of sagittal shoulder motion. They indicate that the developing and adult nervous systems use similar learning strategies to constrain the mechanical degrees of freedom of the arm during skill learning. The findings imply that the employed neural constraints are not age-dependent, but are rather task specific. The study provides further evidence that optimization of joint coordination patterns of complex motor skills is a prolonged learning process that may continue for years. Recovery of balance function in children with cerebellar tumors after surgery and adjuvant therapy Konczak, Juergen; University of Minnesota; Beate Schoch, Dagmar Timmann; University of Duisburg-Essen Lesions in the cerebellum experienced at a young age are said to have lesser consequences for later functioning than similar lesions occurring at later life stages. However, systematic clinical studies on humans are lacking. This study sought to fill this knowledge gap and explored the link between lesion site, motor development, and the restitution of motor performance. Specifically, we examined the effects of posterior fossa tumor surgery and concomitant irradiation and/or chemotherapy on the long-term recovery of balance function in children and adolescent patients. Methods: 22 patients, treated during childhood for a benign (n = 14) or malignant cerebellar tumor (n = 8), were examined in chronic status mean latency between surgery and testing: 7.7 years, range 3–17 years. Postural impairments were assessed with static and dynamic posturography. All cerebellar lesions were documented by standardized and normalized magnetic resonance imaging data. Healthy age- and gender-matched subjects served as a control group. Results: With vision present, the sway area of all patients was normal. However, when vision was blocked and the ground sway was coupled to body sway (sway referenced), a subgroup of patients showed severe signs of postural dyscontrol. Balance abnormalities were most pronounced when a lesion affected the fastigial nucleus, a deep cerebellar nucleus located close to the midline of the cerebellum. Chemotherapy with its neurological side effect was associated with enhanced postural sway in two children with malignant tumors. Yet, in general, the effect of adjuvant chemotherapy and/or radiotherapy on postural control was not severe. Conclusion: The study results indicate that the sparing of the deep cerebellar nuclei had the greatest impact on the recovery of balance function in pediatric patients treated for benign or malignant cerebellar tumors. Muscular and nonmuscular contributions to maximum power cycling in children and adults: Implications for developmental motor control Korff, Thomas; Brunel University; Elaine L. Hunter, James C. Martin; University of Utah During human movement, muscular forces have to be matched to nonmuscular forces to produce a resultant force that complies with the goal of the task. Nonmuscular forces are directly related to segmental mass and inertia. Since relative and absolute anthropomet-
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ric characteristics change during childhood, observed developmental differences in the application of muscular forces could be functional adjustments to account for changes in anthropometry. Brown and Jensen (2006) demonstrated that during submaximal cycling, the distribution between muscular and nonmuscular forces becomes more adultlike if mass is added to children’s limbs. In related work on development of neuromuscular power, Martin et al. (2000) reported that maximum cycling power in children did not significantly differ from that of adults when power was normalized to lean thigh volume. These results suggest that if the external power output is not prescribed, children choose to construct the task in a way that accounts for their different anthropometric characteristics. The purpose of this study was to examine muscular and nonmuscular power production by children and adults during maximum power cycling. Eleven children ages 8–9 and 13 adults ages 20–40 performed a maximal isokinetic cycling task over 3 s at 115 rpm. Using inverse dynamics, muscular and nonmuscular power contributions were calculated from pedal reaction forces and leg kinematics. Hotelling’s t test revealed no significant differences in normalized maximum and average positive non-muscular power between children and adults (Hotelling’s T 2 = 5.48, p = .21). We conclude that during maximum cycling the distribution between muscular and nonmuscular contributions to external power is similar in children and adults. Therefore, maximum cycling is a developmental “self scaling” task, and age-related differences in muscular force application are not confounded by differences in anthropometry. This information is useful to researchers who wish to employ maximum cycling to study the development of muscular power production. Changes of COP variability across development of sitting posture in typically developing infants Kyvelidou, Anastasia; University of Nebraska at Omaha; Regina T. Harbourne, University of Nebraska Medical Center; Joan E. Deffeyes, University of Nebraska at Omaha; Wayne A. Stuberg, Valerie K. Shostrom; University of Nebraska Medical Center; Nicholas Stergiou, University of Nebraska at Omaha and University of Nebraska Medical Center The purpose of this study was to determine differences in the variability of the center of pressure (COP) as sitting skills improve. Thirty-three typically developing infants participated in the study. All infants scored above –0.5 SD on the Peabody test and were recruited when they were just starting to sit upright. Each came to the lab for two sessions per month, for 4 months. Three trials of sitting COP data for 8.3 s per trial were recorded at each session while infants were sitting unsupported on an AMTI force platform. The COP data were analyzed using measures of the amount of variability present such as root mean square RMS, range, sway path, circle area, and ellipse area for both the anterior/posterior and medial/lateral direction. We also calculated the largest Lyapunov exponent and approximate entropy (ApEn) for both directions, which are nonlinear measures suitable for characterizing structure or complexity of variability. Repeated measures ANOVA with a 2-sided critical value of 0.01 were used for statistical analysis. All nonlinear parameters presented significant differences across stages of infant sitting development, while among the five linear parameters examined only RMS and range presented significant differences across stages. RMS and range presented a statistically significant increasing trend in the AP direction, whereas the opposite was true for the ML direction. All nonlinear parameters presented a statistically significant increasing trend in the AP direction, whereas ApEn in the ML direction presented an increasing trend. In the AP direction, the amount of sway increased, whereas complexity of the sitting pattern was reduced with development. In conclusion, both linear and nonlinear measures
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are sensitive to motor control changes of sitting posture in infants during development, and the use of both types together gives a more complete characterization of development than either can give alone. Results are consistent with the theory of optimal movement variability Stergiou, Harbourne and Cavanaugh, 2006. Sensory, attention, and motor skills (SAM): Developmental complexity of postural control Lazarus, Jo-Anne C.; Julie H. Hunley, University of Wisconsin-Madison; Colin R. Grove, University of Wisconsin Hospital and Clinics Postural control is a complex building block of child development. While the sensory and motor aspects of posture have been extensively researched, the impact of a child’s sensory, attention, and motor skills on postural control have been rarely analyzed together. This study addresses the latter by examining the relationship between sensory, attention, and motor skill (SAM) contributions to postural control in a sample of convenience from a previous study. Thirty children (18 males, 12 females) ranging in age from 6 to 12 years (mean age = 9.6 ± 1.9 years) were assessed on motor skills, attention skills, and sensory organization of postural control using the following tests: the Movement Assessment Battery for Children (M-ABC), the Conners Continuous Performance Test (CPT-II), and the Sensory Organization Test (SOT). Variables of interest were the manual skills, ball skills, and equilibrium subtests of the M-ABC; # of omissions, # of commissions, hit reaction time, and hit reaction time variability from the CPT-II; and the somatosensory, visual, vestibular, and visual preference subscales from the SOT. Linear regression analysis revealed a number of significant relationships between variables. To further delineate individual differences in children across these variables, data on the performance of all children were entered into a k-means cluster analysis using a Euclidian distance measure. Results clustered children into four distinct groups: typically developing (n = 15), motor difficulties (n = 7), visual/postural difficulties (n = 5), and sensory/attention/motor difficulties (n = 3). Discussion centered around the complex interplay of sensory, attention, and motor skills on postural control in the developing child. The results emphasize the high degree of variability across children with “soft neurological signs” of sensory, attention, posture, and/or motor difficulties, and provide relevant information on which to base potential intervention strategies. The development of visually guided reaching during infancy Lee, Mei-Hua; Karl M. Newell; Pennsylvania State University The purpose of this longitudinal study was to evaluate the role of visual feedback of the hand in the development of reaching during infancy. In this study, five infants were observed every other week from 10 weeks to 28 weeks old, which is the time line of the transition of spontaneous arm movements to purposeful reaching movements. Three different sizes of objects were presented to the infants with or without visual feedback of the hand. The visual feedback of the hand was controlled with a cloth texture barrier which blocked the view of the hand but not the view of the object. This design also ensured that the infants could move their arms freely. Data were collected by means of a four-camera ProReflex system (Qualisys Inc., Gothenburg, Sweden) and two video recorders (60 Hz). The kinematic analysis revealed that before onset of purposeful reaching, the infants tended to move their arms more actively when the visual feedback of the hand was available. At the onset of reaching, three out of the five infants showed approximately equal amount number of
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reaching movements when the visual feedback of the hand was available. However, two out of five infants showed more reaching movements when the visual feedback of the hand was available. This manipulation of visual information reveals the distinctive roles that vision plays in the development of prehension in infancy. Effects of contextual interference on children’s performance and learning in pedaling Liu, Ting; Jody L. Jensen; University of Texas at Austin One variable that modifies skill acquisition is contextual interference (CI). Very few studies have examined the effect of CI with children. Further, a review of the developmental literature reveals mixed results regarding the effect of manipulating CI for promoting skill acquisition in children. The purpose of this study was to investigate the optimal practice condition that facilitates skill acquisition for children in different age groups. The key to maximizing the learning effect is to manipulate levels of CI to create an optimal practice environment. Five younger (M = 5.6 years, SD = .53 years) and five older children (M = 8.4 years, SD = .54 years) participated in the study. Participants were randomly assigned to either a blocked or random practice condition. The task was to learn to pedal accurately and consistently at three target speeds (60, 80, and 100 rpm). The baseline test consisted of pedaling at each target speed. In the acquisition phase, children on a blocked practice schedule practiced 20 trials on one target speed (60 or 100 rpm) before moving to practice on the next target speed. Children on a random practice schedule practiced 40 trials in a random order (60 and 100 rpm). The retention test included pedaling at 60 and 100 rpm, and the children were required to pedal at 80 rpm for the transfer test. For older children, blocked practice resulted in better acquisition performance than random practice, but tests of learning, as assessed by retention and transfer tests, were performed better after practice had been conducted in a random order. The younger group assigned to random practice performed better than those given blocked practice on acquisition, retention, and transfer tests. The results of this study suggest that young children are able to gain permanent, learning benefits through random practice without the temporary decrements in performance. A potential explanation for this effect may be the nature of the task—continuous (in this case) versus discrete. Supported by NSF Grant No. 9986221. Physical activity of 3- to 5-year-old children with and without Down syndrome Lloyd, Meghann; Dale A. Ulrich; University of Michigan Physical inactivity and obesity are growing problems among children with intellectual disabilities. There is very little research investigating physical activity in children with Down syndrome (DS) in an objective manner. Motor skill development may also be influenced by a child’s level of physical activity. The purpose of this study was to investigate levels of physical activity in 3- to 5-year old children with DS (n = 42) compared to two groups with typical development (TD)—one group matched for chronological age (CA) (n = 36) and another group matched for mental age (MA) (n = 31). Physical activity was measured by having each child wear an Actical activity monitor secured using a small belt around the waist for 5 days. There were no differences in total time of physical activity measured over the 5 days of monitoring for any group. Analysis revealed a significant main effect for group, F(2, 109) = 4.6, p < .01, on the total activity counts over the monitoring period but no effect of gender; there was also a main effect of group on time spent in moderate-tovigorous physical activity per day (MVPA/day), F(2, 109) = 15.05, p < .01. For sedentary
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and light activity, no differences were found between any groups. The children with DS engaged in less MVPA/day on average than the children matched for CA. When the groups were split by age (3, 4, 5 years) there were no differences between the DS and MA at any age for MVP/day. However, the children with DS spent less time/day in MPVA than the MA group in minutes. There was no effect for gender on any of the activity variables, and age has a positive influence on MVPA. As the children get older, they all spend more time in moderate activity. The evidence from this study suggests that differences in physical activity between children with and without DS are already present at 3–5 years of age. Implications for motor development interventions for children with DS will be discussed. The difference between baseball players and nonbaseball players with movement correction to unexpected velocity change in junior high school students Mori, Shiro; Hiroki Nakamoto; National Institute of Fitness and Sports in Kanoya; Misaki Iteya, Tokyo Gakugei University The purpose of this study was to investigate the difference of skill acquisition between baseball players and nonbaseball players in junior high school students with movement correction in a coincident timing task that included unexpected changes in target velocity. In particular, we focused on the rate of movement timing correction that is applied to counter unexpected change in the velocity of a moving target under given time constrains. The participants comprised baseball players and non-baseball players of junior high school students (n = 20). The task was to manually press a button coinciding with the arrival of a moving target, running on a straight trackway. The target moved from one end of the trackway at a constant velocity, and its velocity was increased or decreased in some trials when it reached the other end of the track with a moving target velocity change (TAVC; time-to-arrival after velocity change; Teixeira et al., 2006) from 100 to 300 ms. Results showed that baseball players of junior high school were more efficient in movement timing correction at acceleration condition. These result indicated that baseball players in junior high school students can correct movement timing more efficiently than nonbaseball students when velocity increases. However, in a previous study of University students (Nakamoto and Mori, 2007), the differences in the rate of movement timing correction between two groups (players vs. nonplayers) were more evident when the velocity decreased than when it increased. This suggests that the mechanism of movement timing correction in response to an unexpected velocity change involves the influence of expertise and motor development. Atypical handedness effects on bimanual motor coordination in adults with Down syndrome Mulvey, Genna M.; University of Michigan; Shannon R. Ringenbach, Arizona State University Previous research with unimanual motor performance has suggested that there may be reduced motor asymmetries between hands in people with Down syndrome (DS). However, research on bimanual motor performance has included only right-handed (RH) people with DS despite a high prevalence of non-right-handed (NRH) people with DS. This study examined handedness and perceptual-motor integration effects on bimanual coordination to determine if adults with DS would lead with the preferred hand and perform more stable movements with the preferred hand found in people with typical development. Participants included 13 NRH adults with DS, 22 RH adults with DS, 16 NRH, and 21 RH adults with typical development as a comparison group for chronological age (CA), and 15 NRH and
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22 RH children with typical development as a comparison group for mental age (MA). Participants performed bimanual drumming with auditory, verbal, and visual instructions with movements recorded by a 3-D Ultratrak system. The interaction between group and handedness on mean relative phase, F(2, 98) = 3.37, p = .04, indicated that CA and MA groups led by the preferred hand whereas the group with DS displayed a trend toward leading with the nonpreferred hand that approached significance. Post hoc analysis of the interaction between group and handedness on standard deviation of relative phase, F(2, 98) = 4.00, p = .02, indicated that RH participants performed more stable coordination patterns than NRH participants within both the MA and CA comparison groups. By contrast, NRH participants performed more stable coordination patterns than RH participants within the group with DS. Although the direction of hand performance in people with DS was not predicted by models of motor coordination or previous literature, results are consistent with the Haken, Kelso, and Bunz (1985) model of motor coordination in those performing closer to the intended movement pattern (e.g., RH participants in the MA and CA groups, NRH participants in the DS group), displayed the more stable coordination patterns. New walkers with Down syndrome cautious but effective strategies for crossing obstacles Mulvey, Genna M.; Beverly D. Ulrich, University of Michigan Down syndrome (DS) affects cognitive abilities and motor skills, contributing to delayed onset of walking in babies with DS compared to peers with typical development (TD). New walkers with DS show more mature walking at onset than new walkers with TD, including reduced medial-lateral sway, and greater use of pendular dynamics (Kubo & Ulrich, 2006). However, little is known about how DS affects new walkers’ strategies for approaching everyday problems like obstacles. Typical strategies cited in the literature include (a) avoidance (e.g., stopping, changing directions), (b) switching to crawling (e.g., continuing to crawl or returning to walking after the obstacle), (c) errors (e.g., falling, hitting the obstacle when trying to walk over), or (d) successful walking (e.g., discontinuous or continuous) while clearing the obstacle (Kingsnorth & Schmuckler, 2000). In this study, we used a Peak Motus motion capture system to record the gait of 10 toddlers with DS and 10 toddlers with TD as they walked on a GAITRite mat with a padded bar (13 cm height) placed midway along the path and perpendicular to the mat. We tested infants twice: after 1 month and after 3 months of walking experience. We behavior-coded using the four strategies cited above. We conducted a 2 (group) × 2 (time) × 4 (strategy) ANOVA with repeated measures, which revealed significant differences across strategy, F(3, 16) = 56.21, p < .001, and a Group × Strategy interaction, F(3, 16) = 4.73, p = .02. Post hoc analysis revealed that toddlers with DS were most likely to crawl over the obstacle (48%), whereas toddlers with TD were most likely to fall or hit the obstacle while walking over it (48%). Toddlers with DS did not use avoidance strategies (0%), whereas toddlers with TD were least likely to use crawling (6%) or avoidance (6%) strategies. Overall, toddlers with DS selected more conservative crawling strategies to cross the obstacle, which may have reduced postural control requirements and, thus, reduced risk of falls. Toddlers with TD were more likely to try to walk over the obstacle. Effects of practice on grip force control in children with DCD: A case study Oliveira, Marcio A.; Davi Mazala, Junfeng Huang, Jae Kun Shim; University of Maryland– College Park; Jill Whitall, University of Maryland–Baltimore; Jane E. Clark, University of Maryland–College Park
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Earlier studies have shown variable grip force responses in children with developmental coordination disorder (DCD). In this study, we examined the effect of practice on grip and load force and their relationship in two boys with DCD (9.3 ± 0.3 years) and two age-matched controls without DCD (9.1 ± 0.4). Children with DCD were diagnosed by a pediatrician and scored below the 5th percentile on the Movement Assessment Battery for Children (MABC). The two typically developing (TD) children scored above the 30th percentile. The children practiced on four consecutive days (30 trials/day), performing an accurate grip force ramp task using a customized gripper, instrumented with three piezoelectric sensors. A computer screen provided visual feedback of the load force applied by pulling the gripper. Two boys (with and without DCD) practiced at a constant force level across the days (constant practice) and the other two boys practiced at three different force levels across the four days (variable practice). Retention and transfer were measured five days after the last day of practice. Grip force magnitude, accuracy and variability of load force, and accuracy of force regulation and force ratio (grip force divided by load force) were evaluated for the steady force output phase of the ramp task. With practice, all children improved the variability and accuracy of their load force control. Across practice conditions, children with DCD showed higher variability and lower accuracy as compared to TD children. Our findings from this case study analysis suggest that children with DCD can use feedback to correct their errors and, with practice (constant or variable), they can improve their ability to “tune” their grip force. These data suggest that constant practice may be a better strategy for children with DCD to improve they ability to calibrate the steady force output, but variable practice may help them to improve the ability of force ratio control. Children with developmental coordination disorder: Gender differences in a sample of Brazilian children Pellegrini, Ana M.; Pâmela Bellan, Marcela C. Ferracioli; Universidade Estadual Paulista; Cynthia Y. Hiraga, Universidade de São Paulo In recent years, a large number of studies have been dedicated to examine issues associated with developmental coordination disorder (DCD). A few of these studies have focused on the environmental and cultural influences on motor abilities. The current study examines in a sample of Brazilian children: (1) gender differences in the performance of motor abilities and (2) score differences between fine motor coordination, balance, and ball skills. Participants were 838 children (396 boys and 442 girls), aged 5 to 10 years, from a public school located in the municipality of Limeira, Sao Paulo State. Motor abilities were assessed using the Movement Assessment Battery for Children (M-ABC). Categorical data were analyzed with the chi-square test and continuous data were analyzed using the Kruskal–Wallis test. Taking into account the standard established by Henderson and Sugden (1992) to diagnose an individual as DCD (i.e., total test score below the 5th percentile), it was found that 7.75% (65) of the total children assessed were diagnosed as DCD, in which 45 were girls and 20 were boys. Furthermore, the proportions of children found with DCD for each age group (5–6, 7–8, and 9–10 years) were 6.18, 6.97, and 10.56%, respectively. In contrast to previous research, the present study found a significant greater proportion of girls (10.18%) diagnosed as DCD than boys (5.05%) (p < 0.05). With respect to mean score, children perform better in all M-ABC tasks (eight tasks in total) as they become older. Of interest were the performances in ball tasks showed by boys aged 7–8 and 9–10 years, which were significantly higher compared with girls of the same age groups (all p < 0.01). Our data suggest that the tasks that comprise ball skills in the M-ABC Test appear to influence girls’
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total score. It is possible that performance differences in ball skills between boys and girls might be associated with environmental and cultural influences. Adaptive postural control in children Polastri, Paula F.; University of Sao Paulo State and Cruzeiro do Sul University; Daniela Godoi, University of Sao Paulo State and Centro Universitario Central Paulista; Matthias Weigelt, Bielefeld University; Tim Kiemel, John J. Jeka, University of Maryland; Jose A. Barela, University of Sao Paulo State The coupling between body sway and sensory stimuli needs to continuously be adjusted in order to achieve stable upright stance control. In this study, we investigated age-related changes of how children’s postural control adapts to abrupt changes in the surrounding visual environment. Thirty children aged 4-, 8-, and 12-year-old and ten adults remained in upright stance inside a “moving room” for eight trials of 60 s apiece. In the first trial, the room was stationary and, in the following trials, oscillated at 0.2 Hz with a velocity of 0.6 cm/s and amplitude of 0.5 cm, with the exception of the fifth trial, in which the room oscillated at a higher velocity and amplitude (3.5 cm/s and 3.2 cm, respectively). The results showed that all groups responded to the 0.2 Hz visual stimulus. Body sway responses of all participants decreased to the visual stimulus when the velocity and amplitude of the room increased, indicating decreased coupling (down-weighting) of the visual stimulus. However, gain values decreased more in 12-year-old children and adults than in 4- and 8-year-old children. Moreover, in trials following the high-velocity trial, gain values were lower than in previous trials with adults and 12-year-old children, showing lower values than 4- and 8-year-old children. Sway variability at frequencies other than the stimulus frequency (residual variability) decreased with age and was largest during the high-velocity trial. These results indicated that even children at age of 4 years have developed the adaptive capability to quickly down-weight sensory stimulus influences due to abrupt changes in the surrounding visual environment. However, the higher gain values and residual variability observed in 4- and 8-year-old children suggest that they have not fully calibrated their response to the level of old children and adults. Such adaptive behavior may be crucial for the development of postural control. The effect of external cueing on the end-state comfort effect in at-risk preschoolers Robinson, Leah E.; Mark G. Fischman, Auburn University The end-state comfort effect refers to an individual’s attempt to minimize awkward hand and arm postures at the end of object manipulation tasks, rather than the beginning (Cohen & Rosenbaum, 2004). The effect has been found in many studies of adults (Cohen & Rosenbaum, 2004; Fischman, Stodden, & Lehman, 2003) but recent research with typically developing preschoolers and kindergartners has failed to show the effect (Adalbjornsson, Fischman, & Rudisill, in press; Manoel & Moreira, 2005). This study examined the effect of external cueing on the end-state comfort effect in preschoolers who are at-risk of educational failure and/or developmental delays. Participants were age-matched and purposely assigned to an external cue (n = 14) or no-external cue (n = 15) group. Each participant was given three trials to use one hand (child’s preference) to turn over a cup and pour water into the cup with a pitcher. For the external cue group, yellow squares were placed on the bottom of the cup and on the tabletop, one to the left and one to the right of the child. Participants were asked to “match the yellow square on the bottom of the cup with one of the yellow squares on the tabletop.” The end-state comfort effect was considered present if the
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awkward initial grip (thumb-down) appeared in at least two of the three trials. Chi-square analysis indicated no significant differences (p > .05) between the number of participants exhibiting the end-state comfort effect (n = 13; 44.8%) and those not exhibiting the effect (n = 16; 55.2%). In terms of the effect of external cueing on end-state comfort, chi-square analysis revealed no significant differences (p > .05) between the use of an external cue and no external cue to encourage the use of an end-state comfort strategy. Overall, six participants (42.9%) from the external cue group and seven (46.7%) from the no external cue group demonstrated end-state comfort. The findings suggest that external cueing might not be an effective means of promoting a mature pattern of hand and arm postures during manipulation tasks in at-risk preschoolers. The effect of motor skill instructional climates on perceived physical competence in at-risk preschoolers Robinson, Leah E.; Mary E. Rudisill, Auburn University; Jacqueline D. Goodway, Erica N. Johnson; Ohio University Researchers suggest that the type of instructional climate adopted by teachers influences the learners’ perceptions of competence, altering their intrinsic desire to learn (Ames, 1992). This study examined the effects of a 9-week low autonomy (LA) and mastery-oriented (MMC) motor skill intervention on perceived physical competence (PPC) in disadvantaged preschoolers. Participants were randomly assigned to a LA (n = 38), MMC (n = 39), or comparison (n = 40; no motor intervention) group. The LA and MMC groups participated in 18 30-min motor skill sessions and the comparison group participated in the same number of unstructured recess sessions. Pretest, posttest, and retention test data were collected using the Pictorial Scale of Perceived Competence and Social Acceptance. A 3 Treatment (LA, MMC, Comparison) × 3 Time (Pre, Post, Retention) ANOVA with repeated measures on time revealed a significant Treatment × Time interaction, F(4, 228) = 45.76, p < .001, η2 = .45). Simple main-effects tests revealed no statistically significant difference (p = .17) in PPC scores among participants at pretest. Statistically significant differences were found in posttest (p < .001) and retention test (p < .001) PPC scores. Post hoc Tukey analysis indicated that MMC participants demonstrated significantly higher PPC scores compared to the LA (p < .001) and comparison (p < .001) groups at the post- and retention test. Further analyses investigating within-group differences revealed that PPC scores significantly improved from pretest to posttest for MMC participants (p < .001), whereas the LA (p = .01) and comparison (p = .01) participants demonstrated no changes over time in PPC scores. From post- to retention test, PPC scores remained the same for MMC (p = .32) and comparison (p = .59) participants, whereas LA participants demonstrated a significant decrease in PPC over time (p < .001). The findings support that MMC leads to positive psychological benefits as it relates to perceived competence and achievement motivation in young children whereas low autonomy climates and unstructured recess result in less desirable outcomes. Bilateral self-selected frequency finger tapping in children with and without developmental coordination disorder and in adults Roche, Renuka; Anna Maria Wilms-Floet, University of Maryland–Baltimore; Jane E Clark, University of Maryland–College Park; Jill Whitall, University of Maryland–Baltimore Children with developmental coordination disorder (DCD) are more variable in timing their fingers to a concurrent or preceding external cue, indicating a problem with auditory-motor coupling. It is not clear whether this variability is fundamental to the neuromotor system of
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those with DCD or a function of their ability to match their finger taps to an external cue. In this study, we investigated the intrinsic coordination properties of self-selected anti-phase finger tapping with and without vision and audition in children with and without DCD and compared their performance to that of the adults. Ten children with DCD (mean age = 7.12 ± 0.3 years), 10 age- and sex-matched typically developing (TD) children, and 10 adults participated in this study. Participants tapped their fingers at a self-selected speed under four different sensory conditions: (1) with vision and audition, (2) with vision but no audition, (3) with audition but no vision, and (4) without vision and audition. The variables of interest were frequency of tapping, variability in frequency of tapping, mean relative phasing (RP) between the fingers, and the variability in RP. Analyses showed no significant differences in tapping performance in the absence of vision and/or audition, across all groups. Across all sensory conditions, children with DCD tapped at a similar mean frequency, but with greater variability than the other groups. TD children were more variable than the adults. Children with DCD also were less coordinated between their fingers and were more variable in this coordination than other groups. Overall, regardless of the sensory condition and external cues, children with DCD are more variable in their tapping frequency and coordination. Development of gait periodicity in new walkers with Down syndrome: A mathematical perspective. Smith, Beth A., University of Michigan; Nick Stergiou, University of Nebraska at Omaha; Beverly D. Ulrich, University of Michigan The first step to applying nonlinear analysis to gait is to show that the data are deterministic and periodic. This is a challenge when working with the data of new walkers with Down syndrome (DS), who demonstrate extremely variable and “noisy” kinematic data. In this study, we investigated the emerging mathematical definition of periodicity of early walking in toddlers with DS using surrogation analysis. We analyzed the gait data of nine toddlers with DS at 3, 4, 6, and 8 months of walking experience. All participants were part of a larger longitudinal study in the University of Michigan Motor Development Lab. As part of the data collection, participants walked on a treadmill with close supervision at 75% of their self-selected over-ground walking speed. We used a 6-camera Peak Motus system to capture joint marker locations. Surrogate data were produced for all knee joint location time series data using Theiler’s algorithm (Theiler et al., 1992), in which the data are simply shuffled to produce a random equivalent with the same descriptive statistics. We calculated Lyupanov exponent (LyE) values to compare the original and surrogate data (Sprott & Rowlands, 1992) using an embedding dimension of 8. As randomly generated equivalents of the original data, the LyE values of the surrogate data should be larger than that of the original data, reflecting the deterministic periodic structure of the original data as toddlers walk with alternating leg movements. Larger LyE values were obtained for vertical direction surrogate data as follows (percentage of all trials): 3 months walking experience (50%), 4 months (86%), 6 months (67%), and 8 months (86%). Our analyses of the movement of knee position in the anterior-posterior and medial-lateral directions almost always failed the surrogation test. Our results indicate that as walking experience increases we get more deterministic periodic data. The mathematical procedure used can assist in the investigation of motor delays and the efficacy of early interventions. On the stability and flexibility of walking patterns in 4-, 6-year old children Snapp-Childs, Winona; Purdue University
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Learning to walk is a protracted process lasting well into childhood. Much research has studied how children control their bodies when walking in unobstructed environments. However, less is known about how children manage to navigate cluttered environments, especially where obstacles are located in the walking path. In this experiment, we aimed to explore the changes in coordination of young children’s walking patterns when confronted with an obstacle along the path. To do so, three distinct barriers (a foam obstacle, a gap, and a single step) were placed in the walking paths (two steps from the starting point) of 4-, 6-year olds and adults and observed their walking patterns as they approached and crossed the obstacles. Continuous relative phase profiles were created for each step for both the thigh-leg and legfoot (intralimb) segment comparisons and changes in coordinative patterns were assessed using cross-correlation (performed within condition and step) and root-mean-square (RMS) difference measures (computed between conditions but within steps). Overall, the adults’ coordinative patterns were the most consistent (highly correlated). There were age-related RMS differences for the thigh-leg comparison only; this was observed in the 2nd step but the effect dissipated by the 4th step (2nd step over obstacle), where age-dependent differences were replaced by condition dependent differences. The gap task yielded the least differences, whereas the foam obstacle task yielded the largest differences. These results indicate that the children’s walking patterns were less stable than adults’, as one would expect, but that children were generally as flexible as the adults in adapting their coordination patterns to meet varying task demands. Comparing the pattern of results for stability and flexibility, it seems that higher instability does not indicate that a system is more flexible as has been suggested by some previous research. To the contrary, the improved functionally effective flexibility of the adult is reflected in the superior stability of the behavior. Are babies with myelomeningocele able to adapt to speed when supported on a motorized treadmill? Teulier, Caroline; Beth Smith, University of Michigan; Vickie Moerchen, University of Wisconsin-Milwaukee; Beverly D. Ulrich, University of Michigan Motor patterns must be adaptive to be functional. Infants with myelomeningocele (MMC) have a spinal cord lesion that compromises the sensorimotor system. In our previous work we showed that infants with MMC produce steps when supported on a treadmill across their first year of life. Here we ask if their system adapts to changing constraints (speed), specifically at the interlimb and intralimb level. We studied 12 infants with MMC and 12 with typical development (TD), longitudinally, at ages 1, 3, 6, 9, 12, and 18 months. We supported them on a treadmill for 10- to 20-s trials (2 at each of 5 speeds) with speed increased incrementally across trials from .068 m/s to .22 m/s. Reflective markers were placed on leg joints and EMG electrodes on leg muscles. Data were captured via a 6-camera Peak Motus system; a digital video camera (60 Hz) was synchronized with the Peak and EMG data. Here, we analyzed behavior-coded step patterns (alternating, single, parallel, double) and temporal characteristics of intra- and interlimb behavior. At the interlimb level , 2 (group) × 5 (speed) ANOVA within months showed a speed effect after 1 month (p < .05), with infants with TD increasing alternating step frequency with speed, and infants with MMC did so only at 9 months. Speed increased phase lags for infants with TD until they stabilized around .5 at 6 months; infants with MMC did not respond to speed, producing varied phase lag at all ages. In contrast, within-limb leg trajectories of infants with MMC seem more similar to those of their peers with TD; both showed a decrease in cycle, swing, and stance durations with speed at each visit. In sum, infants with MMC seem to adapt well their intralimb but not
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interlimb step patterns. Perhaps this is because within the step motion limbs tend to adopt pendular qualities, influenced by gravity and motion-dependent torques, as well as the motion of the treadmill belt. Further analysis will be conducted to see if this difference between the intralimb and interlimb adaptation is supported by more detailed kinematic analyses. Improvement in developmental skill level during striking with the use of teaching cues Thomas, Kathleen S.; Linda M. Gagen, Old Dominion University The purpose of this study is to identify if there is any skill development improvement in children during a striking task when observed before and after administering teaching cues. Participants: Fifteen children (6 boys; 9 girls) aged 8–11 (8.93 ± 1.2) involved in a tennis camp at the local university volunteered to participate in the study. Methods and Materials: Consent was provided by parents and assent was provided by children prior to participation. Each child used a tennis racket provided by the camp to perform a forehand groundstroke before and after teaching cues were provided. All sessions were videotaped for later analysis using 2 (Sony DVR-DCR-HC42) cameras placed at 90º to each other about 30–40 feet from the child to view sagittal and frontal planes to categorize developmental levels. A tennis ball was mounted on a 10-S Supply TA116 Stroke (stationary) trainer with a moveable arm to allow for full contact of the ball. Two conditions were performed. Conditions included (1) contact with ball without teaching cue and (2) contact with ball after administering three targeted teaching cues. Developmental levels were identified for three components of striking. Four parameters were identified for both the racket action and the stepping action. Three parameters of trunk rotation were identified. Data Analysis: Paired samples t tests were conducted. Alpha level was set a priori at p < .05. Results: There was a significant difference in developmental levels in racket action, .73 ±. 46, t(14) = 6.2; trunk rotation, .67 ± .49, t(14) = 5.29; and foot action, 1.47 ± .83, t(14) = 6.81, when teaching cues were given than without teaching cues. Conclusions: Changes in developmental level of a sidearm striking task (such as a forehand groundstroke) can be observed in both boys and girls when teaching cues are administered to the children. These changes occur in all of the main components related to sidearm striking, such as racket action, trunk rotation, and foot action.
Journal of Sport & Exercise Psychology, 2008, 30(Suppl.), S61-S144 © 2008 Human Kinetics, Inc.
Motor Learning and Control* Activation of the brain’s mirror network in anticipatory tasks Abernethy, Bruce; University of Hong Kong; Michael J. Wright, Brunel University; Robin C. Jackson, University of Hong Kong The purpose of the study was to identify brain regions involved in the completion of anticipatory tasks of the type commonly used to examine perceptual expertise in sport. In a block-design fMRI study, 5 novice and 6 skilled badminton players viewed 2-s visual displays of badminton strokes executed by an opposing player. Both full video and point-light display versions were generated, with individual trials occluded either 80 ms before or 80 ms after racquet-shuttle contact. The participants were required to predict the direction of the stroke they were viewing by using a button-press response to indicate in which one of four possible court positions the stroke would land. Relative to moving or stationary control stimuli, completion of both the video and point-light versions of the anticipatory task activated the brain’s mirror network in the parietal lobe, precentral gyrus, and inferior frontal cortex. Activations overlapped strongly for the pre- and postcontact occlusion conditions presented via video display, with the more skilled group showing more widespread activity for the precontact occlusion conditions, whereas the novice group showed more widespread activity for the postcontact occlusion conditions in which shuttle flight was visible. Activations were less widespread overall for the point-light displays than the video displays and within the mirror areas there were many regions of non-overlap. For point-light stimuli, both skill groups showed a greater spread of activation (within mirror areas) for trials occluded postcontact rather than precontact. It is concluded that fMRI has potential to extend existing understanding of expertise in anticipatory tasks derived from behavioral measures and appears useful for differentiating sensitivity to temporal occlusion, to dynamic versus static cues, and to different levels of expertise. Mechanisms underlying visual cue strategies for improving gait in Parkinson’s Almeida, Quincy J.; Joshua Vlasic, Wilfrid Laurier University While the benefits of visual cue strategies to improve walking have been well documented in Parkinson’s disease, the mechanism underlying these improvements is poorly understood. The goal of this study was to explore how visual cues lead to improvement in PD gait, when vision of the moving limbs has been removed. The influence of transverse ground lines and additional external peripheral cues on gait was evaluated in 32 participants. Twenty-two participants with idiopathic PD were tested in their normally medicated state and contrasted to 10 healthy participants. Conditions included a self-paced normally lighted room condition (baseline), self-paced in dark condition (dark), dark with glowing transverse ground lines (optic flow −), and dark with glowing transverse lines plus additional external cues *The abstracts are alphabetically arranged by the first author’s surname within each of the four sections—Interdisciplinary, Motor Development, Motor Learning and Control, and Sport and Exercise Psychology. S61
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providing reference information about the dimensions and locations of the surroundings (optic flow +). All participants performed 5 trials in each of the 4 randomized conditions. Dependent measures included all spatiotemporal aspects of gait and the step-to-step variability (as collected on a GaitRite data-collecting mat). In contrast to baseline light and dark conditions, step length significantly improved with the provision of visual cues, F(3, 90) = 6.71; p < 0.0004; however, velocity, cadence, and step time significantly worsened. The PD group also demonstrated a significant increase in step-to-step variability for both step length and step time. These results suggest that individuals with PD may encounter a timing deficit when vision of the limbs is not available. Results will be discussed in terms of whether this may be indicative of a proprioceptive impairment that contributes to gait deficits in PD. Funded provided by NSERC Effect of visual background and delay on estimates of reachability Ammar, Diala F.; Lebanese American University; Carl P. Gabbard, Texas A&M University This experiment examined the role of visual representation in judgments of perceived reach. More specifically, we examined whether or not visual background information facilitates visually guided and memory-guided estimations of reach. Theoretically, with memory-guided reaching via a delay paradigm, the response can no longer be specified in an egocentric visual frame; therefore, target information is thought to be encoded via allocentric cues— in this case, performance typically declines. One limitation of previous work is that none addressed whether or not a visual background (VB) facilitates or impedes the accuracy of memory-guided actions performed across different delay intervals. Krigolson and Heath (2004) addressed this problem by examining the kinematics and the end-point accuracy in visually guided and memory-guided actual reaching conditions and found that VB cues for target location can be used in conjunction with egocentric limb and visible or stored target information to facilitate online control processes. The work presented here builds on that study by examining the combined use of egocentric and allocentric frames in the context of accuracy in estimation of reachability via motor imagery—is the target within or out of grasp? In essence, can visual frames be integrated to facilitate the accuracy of estimates of goal-directed reaching movements? Right-handed adults were asked to give verbal estimates of reachability in two conditions: a no-visual-background and a visual-background condition. In each condition, four delay segments were used: 0, 1, 2, and 4 s. The key finding was that participants performed better in the VB condition when delay was introduced. These data suggest that in memory-guided conditions, VB improves estimates of reach, which is hypothesized to be a key factor in motor programming. Angular momentum regulation during walking Bennett, Bradford C.; Shawn D. Russell, Mark F. Abel; University of Virginia Research has shown that the angular momentum of the body about its center of mass is highly regulated. This has led researchers to suggest that the primitives of the dimensionless spin angular momenta of the body are invariant with walking speed (Popovic, 2004) and thus may relate to the control of walking. This has been the basis of the development of several control strategies applied to walking robots. However, there is a scarcity of data to support this claim. The present work is a retrospective analysis of 11 adults walking overground
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at 0.7, 1.0, and 1.3 times their comfortable walking speed (CWS). A full body marker set of 38 markers was applied to subjects and gait was measured with an eight-camera Vicon system. A 12-segment model of each subject was created and the angular momentum of each segment about the subject’s CoM was computed. We found that the momenta were highly regulated during walking and the spin momenta, L/(Mass·Height·Speed), remained small throughout the gait cycle ( 0.9. Principal component analysis was performed on the spin angular momentum of matrix composed of the contributions of each body segment. This analysis revealed that the first three angular momentum primitives explain 98% of the walking data for sagittal, transverse, and frontal plane body rotations. In addition, although the magnitudes of the angular momenta were velocity dependent (p < 0.001), analysis showed that the angular momentum primitives were invariant with walking speed. Thus, angular momentum primitives, each relating the angular momenta of the individual segments, may be control parameters of walking, and regulation of angular momenta may be appropriate for the control of forward dynamic walking simulations. Effect of cellular telephone conversation and music volume on braking response time Berg, William P.; David B. Bellinger, Bradley M. Budde, Moe Machida, Gary B. Richardson; Miami University The use of cell phones by drivers may be associated with an increased risk for accidents through distraction of a driver’s attention. Other potential distractions, such as interacting with other vehicle occupants, eating/drinking, and adjusting vehicle controls, are even more frequent than the use of a cell phone in distraction-related crashes. Moreover, potential distractions do not necessarily occur in isolation. For example, music is a ubiquitous contributor to background sounds during vehicular driving and therefore is often present at the same time a driver uses a cell phone. The purpose of this study was to determine the extent to which cell phone conversation interacts with music to influence braking response time in a simulated driving task. The braking response time [the sum of reaction time (RT) and movement time (MT)] of 27 licensed drivers (mean age = 21) was measured in a simulated driving task conducted under six conditions: (a) control, (b) low volume music, (c) moderate volume music, (d) cell phone conversation, (e) low volume music and cell phone conversation, and (f) moderate volume music and cell phone conversation. Cell phone conversation caused braking response time to slow, F(1, 156) = 6.67, p < .05, whereas music had no effect on response time, nor was there an interaction effect. The results for the RT component of response time were similar. As for the MT component, cell phone conversation actually caused braking MT to quicken F(1, 156) = 3.851, p = .05. There was also a nonsignificant trend for music to speed MT, and again, there was no interaction effect. In conclusion, cell phone conversation had a detrimental effect on braking response time, despite the fact that conversation actually caused braking MT to quicken. It is as if participants moved faster in an attempt to compensate for slower RT. As for music, there was little to indicate that low-to-moderate volume music influenced braking response time, nor did music influence the effect of cell phone conversation. Vision for performance in virtual environments: The role of feedback timing Bernardin, Brandon J.; Andrea H. Mason, University of Wisconsin–Madison
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Conventional theory dating back to the days of Woodworth has been that visual feedback during aiming and reach-to-grasp movements is most important during the deceleration phase. Vision is used to update a working action plan via closed-loop control, reducing movement error and variability to ensure accuracy at the target. The current work challenges the conventional thinking of how visual feedback is used during human performance in a virtual environment (VE). The purpose of the current study was to compare kinematic performance during partial feedback conditions in a VE to performance during full vision and no vision conditions. We were interested in how the timing of visual feedback affected action plan formation and execution during a unimanual reach-to-grasp task. Twelve right-handed volunteers performed 80 trials of reach-to-grasp movements at two different target distances: 10 cm and 20 cm. Crude visual feedback about the index finger and thumb position was given under four separate conditions: (1) full vision (FV), (2) vision available up to peak wrist velocity (UPV), (3) vision extinguished upon movement initiation (VEX), and (4) no vision (NV). Results indicated that movement time was similar for both partial feedback conditions and the FV condition, with all three showing a significant improvement over the NV condition. Percent deceleration time was similar for the UPV and FV conditions and significantly smaller than the NV condition. The VEX failed to differ from any other condition. Finger aperture was largest in the NV condition, significantly smaller for VEX and further reduced in both the UPV and FV conditions. The results indicate that vision up to peak velocity is sufficient for optimal performance in a VE. These results suggest that visual information about hand position in virtual environments is used in a primarily feed-forward manner to predict movement outcomes and make corrective movements. These results are discussed within the context of differences between performance in natural versus virtual environments. Sensori-motor gating of tactile input during reaching Binsted, Gordon; University of British Columbia; Gavin Buckingham, University of Aberdeen; Matthew Heath, University of Western Ontario; David Carey, University of Aberdeen Sensory predictions arising from motor commands have been suggested to be used to distinguish the sensory consequences of our own actions by canceling predicted re-afferent flow and thus identifying error and/or external input (e.g., Bays et al., 2006: PLoS Biol). Accordingly, electrophysiological studies have forwarded the idea that cortical responses (i.e., S1/S2) are suppressed in response to task-irrelevant somatosensory stimuli or concurrent M1 activation (e.g., Staines et al. 2000: Neuroreport). In our research, we examined this sensori-motor gating using a bimanual pointing paradigm. A tactile stimulus (50 ms vibration) was presented to either/neither hand during the interval from visual target onset and for increasing epochs of 50 ms up to 400 ms after target onset: 20 trials for each of the 50-ms epochs and 20 catch trials with no tactile stimulus. Participants were asked to detect the presence and location of the stimulus following the completion of the pointing trial. In addition to examining response kinematics, individual participant detection ratios were fit with a standard four-parameter logistic curve relative to time. Overall, manual aiming responses were largely unaffected by the presence of external stimulation, exhibiting normal spatio-temporal bimanual coupling and end-point precision. In a manner temporally consistent with the suppression of evoked potentials, participant’s ability to detect the tactile stimulation was significantly reduced concurrent with the approximate timing of the initial M1 outflow (RT, 50 ms). Further, this tactile attenuation extended into movement execution,
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a phenomena reminiscent of saccadic suppression exhibited by the oculomotor system. While superficially maladaptive to the task, where tactile input might be task relevant (e.g., obstacle contact), such suppression may simply reflect perceptual sparing—the information may be retained and actively utilized by the unconscious action system (e.g., Binsted et al., 2007: PNAS). Research supported by: NSERC (Canada; Binsted, Heath), Royal Society (UK; Binsted/Carey). Age-related changes in postural sway in visual conditions: Instability or adaptation? Bonnet, Cedrick T.; Claudia Carello, Michael T. Turvey; University of Connecticut Fluctuation in the mediolateral (ML) axis has been shown to be the best predictor of falls in older adults, perhaps suggesting a change in the involvement of a specific postural control mechanism. We examined influences on postural fluctuations in the context of the “constraint triangle” model of postural control. The manipulation of the organismic constraint entailed a comparison of younger adults, 20 years old ± 1, and older adults, 74 years old ± 5. Manipulation of the task constraint required participants either to count the number of appearances of a target letter in a page of text or simply to fixate on a blank page. The assessment of the environment constraint involved manipulation of the structure of the surround or the level of illumination. In three experiments, scanning text relative to viewing a blank page resulted in more ML variability in older participants and less AP variability in younger participants. Nonlinear analyses showed that older adults were dynamically stable in the ML axis, whereas younger adults were dynamically stable in the AP axis. In support of the contention that variability and instability need not be equivalent, we argue that magnification of ML fluctuations by older adults may imply active engagement of the ML postural strategy to facilitate suprapostural task performance. Discussion focuses on why older adults adopt ML postural control under these conditions. This research was supported by the Collaboratory for Rehabilitation Research through a grant from the provost’s office at the University of Connecticut. Role of action observation and action on coding and transfer of movement sequences Boutin, Arnaud; University of Poitiers; Udo Fries, Stefan Panzer; University of Leipzig; Yannick Blandin, University of Poitiers; Charles H Shea, Texas A & M University Sequential movements are thought to be coded in visual-spatial and motor coordinates (Hikosaka et al., 1999). Other theoretical perspectives (mirror neurons, mental imagery, intention superiority perspective) proposed that physical practice is not the only way to acquire motor skills and that observational practice can facilitate learning of a wide range of tasks. The purpose of the present experiment was to use a sequence learning task in order to determine if the type of coding acquired through physical practice, observation of the stimulus, or observation of stimulus and action differs. A 16-element dynamic arm movement sequence was used. Participants in the observation condition were permitted to watch only the effects of a model performing the sequence. In the action observation condition, the observers saw the model perform the task. The physical practice group actually performed the sequence and, of course, saw the effects (feedback) from their performance. Assessment of the sequence coding involved using an inter-manual transfer design utilizing a delayed retention test and two delayed effector transfer tests. In one transfer test the visual-spatial coordinates (position of the targets) were keep the same as during acquisition while in the other transfer test the motor coordinates (same pattern of flexion-extension required)
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were reinstated. We hypothesized participants will be able to learn the spatial code of the sequence by observation and that action observation would lead to enhance learning. Thus, we predicted that observation leads to better visual-spatial transfer whereas physical practice leads to a better motor transfer. Participants learned the sequence through action observation and physical practice, leading to better transfer on the visual-spatial transfer test than on the motor transfer test. Indeed, participants in the action observation group outperformed the observation group on the retention and visual-spatial transfer tests. The results are discussed in terms of an action observation priority effect in coding movement sequences. Examining the interaction between perceptual-cognitive and perceptual-motor skill in expert decision making Bruce, Lyndell; Damian Farrow; Australian Institute of Sport; Annette Raynor, Esther May; University of South Australia The current study applied Starkes, Cullen, and MacMahon’s (2004) proposed model of expert perceptual-motor performance to the examination of decision-making skill in expert netball players. The study highlighted the model’s interaction between perceptual-cognitive and perceptual-motor skills, where, for example, decisions are heavily influenced by physical proficiency. Nineteen expert netball players completed both a video-based decision-making task requiring a verbal response and an on-court decision-making task requiring a physical response. The scenarios presented in each condition contained the same patterns of play but in the on-court condition the patterns were physically acted out “live” in front of the participant who was required to make their decision and pass the ball as they would in a game situation. Scenarios were manipulated to force players into making decisions where there were two legitimate options available but they required different pass lengths (short or long). Players also completed a passing skill test over distances equivalent to the short and long passes required in the coupled test condition. Decision making was superior in the on-court test condition (M = 87%) relative to the video-based condition (M = 76%), t(18) = −5.26, p < 0.01. The passing skill test revealed that the participants were significantly more accurate when executing a short shoulder pass than a long shoulder pass, t(20) = 5.761, p < 0.01. Closer inspection of the short versus long decision-making scenarios indicated that the passing skill of the players was influencing their perceptual-cognitive skill in the on-court test condition but not in the video-based condition. These findings will be discussed relative to Starkes et al.’s lifespan model of the acquisition and retention of perceptual-motor skill. A kinematic examination of the movement components of the Annett pegboard Bryden, Pam J.; Wilfrid Laurier University; Caroline Ketcham, Elon University The Annett pegboard has been used for decades as a valid measurement of the performance difference between the hands in both children and adults (Annett, 1970). Which aspect of the task elicits the performance differences is not well understood. Previous research by Annett, Annett, Hudson, and Turner (1979) showed that the increased movement time of the nonpreferred hand was primarily due to missing the hole more often, which required more corrective movements. As the hands did not differ in the time taken to insert a peg, the authors felt that visual feedback monitoring could not be used as an explanation for the increased number of corrective movements. In the current study, we attempted to replicate the Annett et al. 1979 study. Sixteen right-handed and 7 left-handed participants completed the Annett pegboard, while their movements were monitored using a 3-D motion capture system (Vicon 460). Results indicated that for right-handers, the preferred hand was significantly
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faster than the nonpreferred hand overall. This was not the case for the left-handers, where there were no significant differences between the hands. For both right- and left-handers, movements took longer when transporting the peg away from the body to position the peg than for movements toward the body to retrieve the next peg. In addition, the performance difference between the hands of right-handers was found to be larger when transporting the peg to be positioned. Such an interaction was not found for left-handers. These results suggest that right- and left-handers perform the task significantly differently and that in right-handers the preferred hand is faster and more efficient in achieving the goal of inserting the peg under visual feedback conditions. Learning a complex surgical skill: The effect of self-guided instruction and goal-setting Brydges, Ryan N.; Heather Carnahan, Adam Dubrowski; University of Toronto. Literature suggests that learners who are able to control their access to instructional information during practice experience learning benefits. Further, effective goal setting is an integral part of self-guided learning. Our aim was to determine the effects of self-guided access to information and goal setting on how novices learn wound closure skills. Forty-eight medical students were randomly assigned to two groups: Self-guided learning and yoked. Within each group they were further divided into a process goal group and an outcome goal group. Students in the self-guided group freely accessed an instructional video during practice. The exact portions of the video reviewed by each student in the self-guided group were played for the matched student in the yoked control group. Hand motion efficiency and expert ratings of performances were used to assess group differences on all tests. Analysis revealed that the self-guided students who set process goals performed better than their yoked controls on the retention test. Thus, when using process goals, self-guided access to instruction leads to better learning. However, the performance of self-guided students who set outcome goals and their yoked controls did not differ on retention. Finally, there were no significant differences between the two goal-setting groups. To help understand these results, the frequencies of video viewing for the two self-guided groups were analyzed. The analysis showed that students who set outcome goals watched the instructional video segments more frequently than those with process goals. Thus, the video utilization data raise the possibility that the students who set outcome goals watched the video more frequently to overcome their lack of process goals. Contrary to our expectations, self-guided learning effects were equivocal and setting process goals did not lead to better performance than setting outcome goals when students learned a complex motor task. Examining the information used by football goalkeepers attempting to save penalty kicks Button, Chris; Matthew Dicks, University of Otago In time-pressured situations, athletes perceive advance cues to anticipate future events, leaving them vulnerable to deception (Jackson et al., 2006; Savelsbergh et al., 2002.) This study examined the perceptual information used by association football goalkeepers while attempting to save penalty kicks. One skilled player took penalties with either a deceptive or nondeceptive standardized run-up. Goalkeepers (N = 8) wore Plato LCD occlusion goggles, which were opaque prior to the initiation of the penalty taker’s run-up and became clear at: t1, run-up initiation; t2, kicking foot ground contact prior to the final kicking stride; t3, kicking foot toe-off in the kicking stride; t4, non-kicking foot ground placement; t5, ball
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contact. Ten deceptive and nondeceptive kicks were taken in each condition. The order of presentation of conditions and deception trials were randomized. Goalkeeping performance based on a 5-point scale was significantly better in the nondeception trials compared to the deception trials for the first two occlusion periods (ps < .001). However, information presented after the penalty taker’s kicking foot was lifted in the kicking stride (t3) did not deceive the goalkeepers. An earlier initiation of response time was found as more perceptual information was made available for deceptive and nondeceptive conditions. Goalkeepers use perceptual cues while attempting to save penalties although they are not susceptible to deception late in the kicker’s run-up. The influence of a secondary task on sequence learning Cacola, Priscila M.; Kristin M. Swan, Charles H. Shea, Texas A&M University The present experiment investigated the hypothesis that implicit learning of a serial reaction time (SRT) task is impaired when learning occurs in the presence of an attention-demanding secondary task. A 12-element SOC sequence was used where four squares (stimulus locations) were projected on the computer monitor. When the square was filled with one of four colors, the participant was to depress the associated key as quickly as possible. Immediately upon depressing the correct key, the next square in the sequence was illuminated. This continued until the sequence was completed. The secondary task involved counting the number of times one of the four colors used as stimulus occurred during the block. The unique feature of the present paradigm was that the color in addition to providing the stimulus also provided advanced information on the location of the next stimulus in the sequence. The results indicated that the secondary task impaired performance while it was present during acquisition, although actually resulted in enhanced performance on the retention tests. The tests included sequences where the stimulus and sequence were intact, where the sequence order was changed or the colors were changed. Performance of the sequence was generally enhanced as a result of the secondary task, but utilization of the color cues was only demonstrated for the participants that were not required to perform the secondary task. The role of motor and perceptual expertise in the prediction of deceptive movements Canal-Bruland, Rouwen; Maike Schmidt, University of Muenster Expert basketball players have been shown to outperform novices in detecting deceptive movements in a basketball anticipation task (Sebanz, Zisa, & Shiffrar, 2006). Sebanz et al. (2006) argue that experts show better performances because they simulate the observed action by relying on their own motor repertoire. The aim of the present study was to test whether experts detect and predict deceptive movements more accurately due to their motor expertise or due to their perceptual expertise and visual familiarity with the situation. Subjects (N = 125)—50 expert handball field players, 25 expert handball goalkeepers, and 50 novices—participated in a handball anticipation test. They were instructed to watch 90 randomly ordered video clips presenting four different players performing 7-m-penalties. Half of the videos resulted from trials in which the actors threw the ball at the goal. These videos were temporally occluded one frame before the ball left the hand (throwing condition). The other half of the videos resulted from trials in which the athletes seemed to throw the ball, but finally did not (deception condition). These deception videos were temporally occluded at the same time as the sequences from the throwing condition and were considered “quasi-identical” video clips. The task was to predict as accurately as possible whether
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the presented player would throw the ball or only faked to throw the ball at the goal. The results revealed that there were significant differences in the accuracy scores between the three groups, p < .001, η2 = .43, indicating that expert handball players and goalkeepers outperformed novices. A significant interaction, Condition × Field Position, p < .05, η2 = .06, revealed that expert goalkeepers were better than expert field players in predicting deceptive trials, whereas the reverse was found for predicting throwing trials. These results will be discussed in regards to the influence of motor and perceptual expertise in predicting deceptive intentions of opponents. Effects of startle and increased response complexity on motor preparation and reaction time Carlsen, Anthony N.; Romeo Chua, J. T. Inglis, David J. Sanderson, Ian M. Franks; University of British Columbia When charged with producing a response as soon as possible following a “go” stimulus in a simple reaction time (RT) task, a useful strategy is to prepare or pre-program the required response in advance of the imperative stimulus (IS). It has been suggested, however, that when response complexity is increased by increasing the number of movement components, response programming cannot be completed until after the IS (Klapp, 2003). The purpose of the current experiment was to investigate response programming across differing levels of response complexity using startle. A startle response can act to trigger a pre-programmed response without normal cortical response initiation, allowing it to be used as a probe for response programming (Carlsen et al., 2004; Valls-Solé et al., 1999). Participants performed three wrist-extension movements (15 deg, 30 deg, and a 2-component 15 + 15 deg movement) in a simple RT task. A loud (124 dB) startling stimulus was presented along with the regular (82 dB) IS in several trials. Results showed that the startle led to the early triggering of both the 15 and 30 deg movements. However, the 2-component movement was not triggered directly by startle. These results support Klapp’s dual-process model in which programming of multiple component movements cannot be completed prior to the IS (Klapp, 2003). Perceiving affordances for stair climbing in an environment-person-person system Chang, Chih-hui; National Kaohsiung Normal University; Michael G. Wade, University of Minnesota Affordances, properties of the environment-animal system, describe the relationship between the animal and its environment (Gibson, 1979/1986). Affordances also determine what an animal can do within its environment. Warren’s study (1984) showed that individuals were able to perceive affordances for stair climbing and the optimal and maximal stair height equaled 0.88 and 0.25 of their leg length, respectively. Warren’s study focused on affordances for stair climbing of an environment-animal system. However, in daily living, behavior often has to do with environment and a person plus person system. The purpose of the present study was to determine affordances for stair climbing for a person plus person system. Eight female tall adults (19.92 ± 1.10 years, 175.96 ± 3.00 cm) and 8 female short adults (20.17 ± 0.90 years, 149.09 ± 1.99 cm) were recruited as participants. One tall girl (7.75 years, 134.1 cm) and one short girl (7.42 years, 118.6 cm) served as companions to the participants. Each participant was required to stand still and make judgment about the optimal and maximal bipedal climbable stair height for herself and a tall or a short girl. Results indicated that participants’ height, children’s height, and judgment types were distinguishable in the
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perceived and the actual stair height. Adults’ leg length and leg strength influenced their judgment, perceived and actual climbability. Results will be discussed from the ecological approach to perception and action. Examination of a simplified throwing pattern between different skill levels Chen, Miaowei; I Chieh Lee, Yeou-Teh Liu; National Taiwan Normal University Throwing has been considered as an developmental skill that is improved with maturation (Roberton & Halverson ,1984). However, poor throwing performances were usually observed among college female students. Therefore, the purpose of the study was to examine the difference of the throwing patterns between inexperienced and expert throwers. Eight righthanded female softball players and eight college students who had no extensive experience in throwing were recruited in the experiment. They were instructed to throw a tennis ball from sitting position under 4 different target conditions (far-high, far-low, near-high, near-low). A high-speed camera (200 Hz) was used to record the throwing movements from the sagittal plane, and the Kwon3D software was used for digitization and data derivation. The results showed that the softball players had a larger wrist joint angle at ball release and the shoulder joint angle was kept small during the forward forearm movement. The angle-angle diagram of the elbow-shoulder plot showed a qualitatively distinct movement pattern between the 2 groups during the forearm backward and forward phases, and we were able to quantify these differences for statistical analyses. Although the experimental task was a simplified throwing task, the findings of the differences between the softball players and the inexperienced female college students provide further understanding of the throwing movement and may be applied in PE teaching to improve the throwing skills of the students. Examine the transitory change in learning pedalo locomotion skill Chen, Hsiu-Hui; Taitung University Thanks to the definition that persistent changes characterize motor learning, the transitory changes during learning are usually ignored or averaged out in the measurement of learning or development (Newell et al., 2001). In this study, we investigated the transitory change of warm-up decrement at the beginning of practice session and the perturbation of outliers in learning curves base on the perspective of dynamical system. Four participants practiced pedalo locomotion skill for seven days within 50 trials a day. The difference of whole body movement 15 markers on the joints and the pedals in three dimensions between consecutive trials was calculated and plotted as the learning curves for analysis. The results showed that 15 of 21 warm-up decrement with r2 value larger than 0.3, and only 10 of them were better fitted by exponential function. The change rates of warm-up decrement were faster than persistent change t(9) = 2.47*. The reminiscent performed differently according to the order it appeared before the exponential curves or after, with which larger variability in the former and more stable in the latter. The number of outliers did not decrease as the skill improved; however, the exponential function fitted better for most of the curves beginning from the point of outliers. In conclusion, the pattern of transitory change in whole body movement coordination revealed the characteristic of multi-timescale. The hypothesis suggested by Newell et al. (2001) for transitory change were support partly in this study. Visual perception of table tennis serve in biological motion Chen, Hsiu-Hui; Lian-Zong Yang, Guo-Liang Zhuang; Taitung University
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This study examined the influence of experience of table tennis and viewpoint on the affordance of biological motion (Johansen, 1975). The central question was whether the transformation of joint positions over time provides sufficient information for discriminating the movement pattern of table tennis serve. Ten national table tennis players and 10 novices participated in this study to discriminate the type of serves, which were either side spin harder or top spin double bounce. The same performances were displayed under point-light (PL) and normal image (NI), both left and right visual direction. The participants were required to respond with real movement followed by verbal answer. The consistence and correctness of their responses were recorded for analysis. Three-way ANOVA showed that all the participants performed better for normal image, F = 8.7*. Players were influenced by the viewpoint of NI significantly. A high correlation between PL and NI in left viewpoint were shown, .81*. The players responded more consistently than the novices, 0.98 vs. 0.72. In conclusion, the biological motion provided necessary information for detecting the types of table tennis serves. However, the experience might influence the affordance individually. Can you tell a table tennis from a tennis stroke from biological motion data alone? Cheng, Kuang Chih; Yeou-Teh Liu, National Taiwan Normal University Transfer effect has been an interesting issue in the area of skill acquisition, not only from the research perspective but also in practical applications. For example, many racket sports share some similar but different techniques that an expert in one racket sport, such as table tennis, may simply apply her skills familiar from playing table tennis to a new task of playing tennis. Newell (1986) proposed that the relative motion of markers in biological motion provides the essential perceptual information in identifying the activities. We hypothesized that the point light display of the biological motion contains the invariant information of the specific coordination pattern and the perception of the specific information depends on the affordance of the perceivers. A motion digitizing system, GypsyGyro-18, was used to capture 4 forehand strokes of table tennis and tennis from each of an elite table tennis player, an elite tennis player, and a PE major of college student. Sixty-nine participants with different sport background, expert tennis players, expert table tennis players, and recreational table tennis and tennis players were recruited to view the 24 clips of the biological motion of the forehand strokes and identify whether table tennis or tennis strokes were performed. The 2(viewer level) × 3 (performer) mixed-design ANOVA on the correct answer rate showed a significant performer effect, F(2, 134) = 58.402, p < .05. The post hoc comparisons showed a higher score for the expert performers than the other performers. There were no significant effects on viewing groups and no interaction between main effects. Independent-samples t test also found that expert viewers scored higher than the recreational viewers in identifying the performance of the elite players t(67) = 3.091 p < .05. Theses results provide support for the invariant perceptual information revealed in producing the specific movement patterns, and the superior ability of identifying the expert movement pattern by the expert players also supports the affordance concept in ecological psychology. Behavioral and neurophysiological modulations associated with specific tasks during isometric force production Chiang, Huai-Hsiao H.; Cheng-Kai Hsueh; Chung-Yuan Christian University Recent studies showed multiple factors associated with the control of finger force production as well as movement-related cortical potentials. The control of prominent force is functions of force, directions of force, acceleration, end-effectors, and so on. Past findings emphasized
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on one-dimension or single motor action. The processes and mechanisms associated with varied motor actions are still unknown. This study tries to control length of force output in order to examine specific neural strategies associated with three stages of force, such as up, maintenance, and down phases. College students (N = 10–15) will be required to produce several force-related tasks associated with varied target force, rate of force, and duration by using their four fingers. Force outputs and movement-related cortical potentials were collected for further analyses. The results showed that both force outputs and movement-related cortical potentials of fingers were significant in terms of accuracy, enslaving, and directions of force. Therefore, we assumed that there would subsist different control mechanisms within four fingers in terms of behavioral and cortical outcomes. The results and implications of this study would further explore the behavior-brain relationships. It is suggested that the underlying mechanism of finger coordination or the complex motor system could be recognized neurophysiologically and cognitively. Kinematic influence of attentional focus on putting Coker, Cheryl A.; New Mexico State University Though studies have shown advantages for instructions that induce an external focus of attention versus an internal focus for the learning of a variety of motor skills (see Wulf, 2007, for a review), few have incorporated an analysis of the consequential movement pattern. The purpose of this study was to examine the kinematic influence of instructions that focused participant’s attention on their own body movements (internal focus) vs. those that directed attention to the movement of an implement (external focus). Twenty-one participants were randomly divided into two groups according to the attentional focus instructions received. The task was an eight-foot golf putt. Following a 10-trial pretest, all participants were taught the basic technique of the golf putt with the exception of the description of the stroke. Participants in the internal focus group were instructed to focus on the swinging motion of their arms and those in the external group were directed to focus on the head of the putter. Following the explanation and demonstration, participants performed 8 blocks of 10 practice putts with attentional focus checks and reminders given after each block. After a two-day period of no practice, a retention test consisting of 3 blocks of 10 putts was performed. Data were analyzed using a 2 (Group) × 2 (Test) ANOVA with repeated measures on the second factor. Variables of interest were score, linear displacement of the back and front swings, linear velocity of the putter head at contact, total time of the swing, timing of the back and front swings, and the angular displacement of the wrist. Results do not support previous studies as no significant differences were found between groups on any of the variables of interest. Participants did, however, significantly increase their score from pretest to retention and the corresponding movement pattern revealed a significant increase in both the length and time of the front swing. Consequently, the results of this study indicated that both attentional foci were equally effective for skill acquisition. Cognitive acrobatics: Spatial perception-action coupling of human body rotation. Contakos, Jonas; Les G. Carlton, University of Illinois at Urbana-Champaign The ability to correctly perceive the direction of human body rotation is highly dependent on the orientation of the rotating figure with respect to the observer. The aim of the current study was to investigate the ability of observers to correctly identify the direction of human body rotation when response patterns were varied in spatial orientation. Forty college-aged
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participants watched a series of videos of a computer animated figure (avatar) rotating about the longitudinal axis. The spatial orientation of the avatar was varied from 0 to 360 degrees about the anterior-posterior axis in 30-degree increments. The observers were asked to report the twisting direction of the avatar as fast and accurately as possible with one of the following keyboard button patterns: (1) right button = right twist, left button = left twist, (2) left button = right twist, right button = left twist, (3) up button = right twist, down button = left twist, (4) down button = right twist, up button = left twist. The response times remained consistent across button pattern conditions, whereas the accuracy was highly dependent on the orientation of the avatar relative to the spatial orientation of the specific buttons used to respond. This data suggests that individuals may choose simplicity over accuracy when selecting a set of basic rules during a cognitively demanding spatial orientation task. Observational learning of a bimanual coordination task Dean, Noah J.; John J. Buchanan, Texas A&M University Although extensive research has studied the extent to which demonstration and active participation combined can lead to learning bimanual motor skills, the study of observation alone as a practice method to learn bimanual motor skills has received minimal attention. The primary purpose of the present study was to determine the extent to which a person can learn by observing a model’s discovery learning process. Participants were asked to volunteer in pairs of identical gender, handedness right-arm dominant, and age ~2 years for the study. One participant was randomly designated as the observer and the other the model. The model sat in a chair and traced two 10-cm-diameter circles, one circle for each arm with styli in the horizontal plane at a frequency of 1 Hz. The model was told to coordinate their arms while tracing the circles in order to produce a 90° relative phase pattern between the styli used to trace the circles. A 90° pattern is characterized by one stylus lagging the other by ¼ of a circle. The observer sat in a chair approximately 3 feet in front of the model and was told that they would have to perform the same task after watching the model for two consecutive days. A total of 30 trials were administered per day, for two days. The model and observer received the same performance feedback regarding the model’s performance. Performance feedback was presented in the form of an angle-angle plot. On the third day, the observer and model were asked to perform in different sessions and attempt to produce the 90° coordination pattern with feedback. Both the models and observers showed improved performance during the retention test in comparison to the models’ Day 1 performance at the required 90° relative phase pattern. Transfer performance of the models and observes was poor on tasks requiring the tracing of mixed circle pairs, e.g., a 3-cm-diameter circle paired with a 15-cm-diameter circle. This implies that the learned relative phase became linked with the required 10-cm circle diameter of the practice templates. Effects of experience on timing and force variability in an oscillatory finger force task Dickey, Gwyneth R.; Marcio A. Oliveira, Jeffrey Hsu, Jae K. Shim, Jane E. Clark; University of Maryland One of the pervasive questions in the development of motor control is how a certain type of experience affects a subject’s performance. Piano players, for example, undertake extensive practice of key pressing with individual fingers that requires precise timing control. In this study we studied expert pianists to determine if they demonstrated better force and timing
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control of their dominant hand index finger compared to those with no piano training. Seven adult pianists (23.3 ± 5.0 years old) averaging 17(±5) years of piano training formed the experimental group. Seven age- and gender-matched controls (20.7 ± 2.1 years old) with no piano experience formed the control group. All participants were right-handed based on their hand preference for everyday activities such as writing and eating. Subjects performed an isometric oscillatory finger flexion-extension force production task at 20% of their maximum voluntary finger force production (MVF). During each of ten 30-s trials, all fingers were placed in thimbles attached to two-directional (tension and compression) force sensors. Visual feedback on a computer screen displayed two horizontal fixed boundary lines (20% of MVF) and a third intermediary moveable line representing the subject’s applied force. Subjects were asked to apply finger forces to move the intermediary line consecutively up and down, contacting the boundary lines in synchrony with an auditory isochronous beat from a metronome (60 bpm). Flexion and extension force variability (variance) was measured across time, and the inter-response interval variability (variance of IRI) was measured by the time between force peaks. Although the results showed no effect of experience on the flexion or extension force variability, the IRI variability was smaller for pianists as compared to nonpiano players. No force and timing differences were found between flexion and extension conditions. The results suggest that piano playing can improve individual finger timing movement control without necessarily changing finger force variability. Does whole-body vibration impact postural control in altered and unaltered sensory environments? Dickin, D. Clark; Matthew Gregg, Andrew Aune; University of Idaho Claims of whole-body vibration (WBV) have ranged from increasing power, strength, speed, flexibility, bone density, circulation, and even balance. However, the findings in all of these areas have been equivocal at best. In the majority of studies, often as a limitation of the vibration platform, the frequency of vibration has ranged between 25 and 40 Hz. It has been posited that the vibration causes the muscle spindle to increase its sensitivity and become primed for easier activation in future muscular contractions. To the area of posture and balance this could potentially result in faster activation of the somatosensory system in response to postural sway. In older adults with a reduced functional limit of stability this could result in a decreased level of postural sway as a function of challenges to postural stability. In the current study we assessed the impact of both frequency and amplitude of WBV on postural control in altered and unaltered sensory environments in 12 healthy younger adults. Individuals were assessed prior to and immediately following a 4-min exposure of WBV at 10, 30, and 50 Hz at low (2 mm) and high (5 mm) amplitude displacements. Each individual was assessed on six different occasions such that each combination of high and low amplitude and frequency could be assessed in a random order. All participants completed all testing sessions. In an attempt to minimize any residual effect from the previous WBV exposure, a minimum period of 48 hours was imposed between each test session. Postural sway (elliptical sway area and movement velocity) was assessed using a SMARTEquitest Balance Master under a stable support surface condition and a sway-referenced support surface in both eyes open and closed conditions. Results demonstrated that indeed there was an acute effect of WBV on postural stability with differential effects based on the frequency and amplitude of vibration exposure. Findings from this study will be discussed with implications for future studies and interventions in populations including older adults and those with Parkinson’s disease.
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Visual search and bimanual coordination: Searching for strategies of performance Edwards, Christopher A.; Janet Cybucki, Warren Balzer, Dana Maslovat, Romeo Chua, Nicola J. Hodges; University of British Columbia Difficulties in bimanual coordination have been linked to difficulties in perception of relative phase (RP). Bingham and colleagues have shown that judgments of RP are most stable around 0° and 180° and least stable around 90°, mirroring observations of movement. Further, when judgments of RP are variable, patterns of eye movements are also variable (Huys et al., 2005), although this has only been demonstrated in unimanual movements. We examined the accuracy and stability of perceptual judgments and eye movements during the identification and production of RP patterns in order to determine how vision and perception mediate coordination. Twelve participants of varied task experience were asked to coordinate their hands with pendula and to identify (via foot pedal) changes in RP (3 times with movement and 3 times without). Participants correctly judged a change in RP from 0 > 30°, but with the exception of patterns around 180° they were only able to respond to change in RP on about one third of all trials. Both conditions (perception or perception with movement) showed a similar pattern of results. The gaze location was a function of RP (0, 90, and 180) and condition. For the perception condition, more time was spent fixating centrally for the 0 and 90° plateaus, in comparison to 180°, whereas for the movement condition, more time was spent fixating centrally at 0 RP, than all other plateaus. We expected that participants who demonstrated low error throughout scanning would show consistent eye movement strategies across and within trials and correct identification of a change in RP, coupled with low variability across trials. Although analyses are still underway, 2 participants with low error at the 90° RP pattern adopted different strategies (anchoring versus tracking). However, both participants were relatively consistent across trials. We will further examine the coupling of reaction and movement responses with visual search to determine if specific strategies emerge as a function of ability to perform these difficult RP patterns. Increase practice variability by providing a strategy for learning a novel task Etnyre, Bruce; Rice University It has been hypothesized females benefit more from variable practice than males (Wrisberg and Ragsdale, 1979). One speculation for this is that males tend to attempt transferring previously learned motor programs and ineffective strategies to novel tasks more than females. As a result, females have more varied practice while learning a novel task and the consequence is males perform more poorly and retain less than females. A previous study showed significantly poorer acquisition and retention scores for males compared to females performing a balancing task on a stabilometer. Another study (Wulf, et al., 2003) found performance and retention of the stabilometer task were better for a group given an external focus strategy than a control group. The purpose of the present experiment was to compare performance and retention between males and females after they were encouraged to include the external focus strategy during learning of the novel task. Thirty-seven participants (11 males, 26 females) performed five or ten 30-s acquisition trials on a stabilometer with a retention test one week later. All participants were introduced to the external focus strategy prior to the first acquisition trial. Participants were told to look at a horizontal surface in the room rather than at their feet while attempting to balance. In contrast to previous studies, which resulted in females significantly outperforming males on the stabilometer task, this study found no significant difference, p = .43, for average balancing times between males (mean
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= 21.3, SEM = 0.81 s) and females (mean = 21.5, SEM = 0.73 s) during acquisition and retention after introduction of the external focus strategy. The conclusion from these results suggested learners may be able to improve performance and retention if they are given a strategy or strategies to increase variability of practice, which may reduce their attempts of using previously learned and ineffective motor programs during learning of a novel task. The effects of repeated retention testing and intertask interference on the learning of a simple timing task Fairbrother, Jeffrey T.; Joao A.D.C. Barros, University of Tennessee-Knoxville Magnuson, Shea, & Fairbrother (2004) demonstrated that repeated testing degraded performance during a 24-hr test when a first test was given 23-hr 50-min after acquisition. They argued that the relatively long delay between acquisition and the first test led to faulty re-encoding of task information and speculated that intertask interference should accentuate these testing effects. Although Fairbrother, Shea, & Marzilli (in press) did not support this speculation using a 10-min retention delay, it is possible that the repeated testing effect was dependent upon a longer initial delay i.e., 23-hr 50-min. The purpose of this study was to further test the idea that intertask interference would accentuate repeated retention testing effects by using a protocol that matched the retention delays used by Magnuson et al. Participants were randomly assigned to one of three conditions to learn a sequential timing task. The 1T condition took a single retention test after a 24-hr delay. The 2T and 2TI conditions took retention tests after 23-hr 50-min and 24-hr delays. In the 2TI condition, intertask interference was introduced by requiring participants to complete 30 trials of two interpolated tasks. Results revealed a Condition × Test × Block interaction, p = .008, in CE, which indicated that the accuracy of the 2TI condition degraded across blocks during the second retention test. For VE, results revealed significant main effects for condition, p = .009, and for test, p = .004. During the second retention test, both the 2T and 2TI conditions showed lower VE than the 1T condition. In addition, VE scores were lower during the second test than the first test for all three conditions. These findings in combination with those reported by Magnuson, Shea, and Fairbrother suggested that repeated retention testing effects depend upon the success of the initial encoding of task information as well as the position of the first test. The lack of an intertask interference effect further suggested that successful initial encoding created relatively stable task representations. The use of naturalistic observation to assess movement patterns and timing structure of the take-off maneuver in surfing Fairbrother, Jeffrey T.; Rachel L. Boxell, University of Tennessee-Knoxville In response to recent calls for increased ecological validity in the study of movement skills, naturalistic observation was used to study the take-off maneuver in surfing. The first purpose was to determine the extent to which effective patterns of movement in the take-off maneuver could be observed in a naturalistic setting. The second purpose was to examine the timing structure of the take-off to determine if it was consistent with patterns of movement timing observed in other sports skills (e.g., Chapman, 1968; Hubbard & Seng, 1954; Katsumata, 2007; McLeod & Dienes, 1996). Examination of 68 video segments from 12 participants revealed three distinct phases in the movement. Description of the overall movement revealed shortcomings in conventional wisdom regarding the initiation of the maneuver. To examine the timing structure, correlation analyses were conducted on the relationship between the
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duration of each of these phases and the overall duration of the take-off. Both the first phase preparation-to-stand and the third phase rail-release were reliably correlated to overall duration. Moreover, both of these phases showed high variability in their durations. In contrast, the second phase transition-to standing was not correlated to overall duration and showed very low variability in duration. These results revealed a pattern of timing consistent with the use of the first phase preparation-to-stand to regulate the onset of a rapidly executed second phase transition-to-standing. The third phase rail-release appeared to be used as a corrective mechanism when needed. Based on these results, naturalistic observation appears to be a useful method for examining how surfers perform the take-off maneuver and is recommended as an effective option for the examination of other sport skills. Variability in tournament scores of male professional golfers Fairbrother, Jeffrey T.; Lauren A. Loberg, University of Tennessee-Knoxville There is some disagreement among researchers regarding the extent to which expert performance in sport is characterized by stability (e.g., Abernethy, Farrow, & Berry, 2003; Ericsson, 2003). In the sport of golf, popular instructional publications often stress consistency as a defining aspect of high level performance (e.g., Kite, 1994; Stenzel, 2002). On the other hand, it is not uncommon for professional golfers or commentators to indicate that aggressive play is the key to success despite its inherent risks (e.g., Leonard, 2008), one of which would presumably be increased variability in strokes per hole. The purpose of the present study was to examine hole-to-hole stroke variability (SV), and average number of strokes from par (SFP) for tournament leaders (TL; lowest overall stroke counts) and trailers (TT; highest overall stroke counts) in three PGA tournaments. For SV, a Group (TL vs. TT) × Nine (front vs. back nine) interaction (p = .024) indicated that TL were less variable than TT on the back nine holes but not on the front nine. A main effect for round (p < .001) indicated a general increase in variability across the four rounds. For SFP, a Group × Round interaction (p < .001) indicated that the TL group had lower scores than the TT group during each of the four rounds. Moreover, this difference grew more pronounced across rounds. The TT group showed a dramatic increase in SFP from the first two rounds to the final two rounds of the tournaments whereas the TL group showed only a slight increase from Round 1 to Round 4. A main effect for nine (p = .06) revealed that SFP was lower on the back nine than on the front nine. These findings showed that consistency did indeed distinguish between levels of success in professional tournament golf. A key feature of this difference, however, was that the TL group was able to avoid increased variability when transferring from the front nine holes of a round to the back nine while the TT group was not. The development of expertise once selected into a high performance pathway Farrow, Damian; Australian Institute of Sport Examination of expertise from a multi-dimensional perspective provides a valuable means of determining the relative importance of various components known to contribute to expert performance. Previous multi-dimensional research has typically focused on the measurement of expert and novice performer’s general visual function relative to sport-specific perceptualcognitive skills (Helsen & Starkes, 1999; Ward & Williams, 2003). The current study extended this work by examining the sport-specific perceptual-cognitive and perceptual-motor performance of skilled athletes within a high performance talent development pathway. Netball players from the National U17, U19, U21, and Open squads were examined on their pattern
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recall, decision-making, passing, and reactive agility skills. The aim of the research was to: (1) identify those skill components that differentiate between the various levels of netball expertise and (2) determine how accurately the test battery predicts squad membership. A series of MANOVAs revealed that the open squad members were significantly better than all other squads in pattern recall. Both the Open and U21 squads possessed superior decisionmaking skill relative to the U19 and U17 squads. Passing skill analyses again revealed the superiority of the Open squad, whereas reactive agility was not a strong discriminator among the squads. Discriminant analysis revealed that recall of defensive players and decisionmaking accuracy explained the greatest amount of between-group variability (93.6%), with the Open squad differentiated from the other squads. The model accurately predicted between 25% and 82.4% of group membership. While the importance of decision-making skill to expertise in team ball sports is well established, the role of defensive recall has been implicated only recently. The current findings provide both theoretical and practical implications for skill acquisition and the progression toward elite performance. The constant-random practice: Effects of skill aspects manipulation on adaptation of a perceptive perturbation in adaptive process of motor learning Fialho, Joao Vitor A. P.; Herbert Ugrinowitsch, Federal University of Minas Gerais The aim of this study was to investigate the effects of constant-random practice with manipulation of different skill aspects on adaptation of a perceptive perturbation in adaptive process of motor learning. Thirty-six undergraduate students were allocated in three experimental groups and performed a task that consisted of touching sensors in a pre-determinate sequence in integration with a visual stimulus. The experiment was composed by two phases: stabilization and adaptation. The stabilization phase was divided into two stages: one with constant practice and another with random practice, which guided the three formed groups with perceptive, motor, and perceptive-motor skill aspect variation, respectively. Due to that, the perceptive group practiced three velocities of the visual stimulus in the random practice, the motor group practiced three sequences, and the perceptive-motor group practiced the combination of three velocities of the visual stimulus with three sequences. In the adaptation phase, the subjects practiced the same sequence practiced in the constant practice stage but with a new velocity of the visual stimulus. The measures used in this study were divided into performance measures (absolute error and variable error), skill microstructure measures (magnitude and variability of overall movement time), skill macrostructure measures (magnitude and variability of five relative time components), and complementary measures (trials to achieve the performance criterion and eliminated subjects). Altogether the results of this experiment allowed to conclude that (a) it seems to have a hierarchy of difficulty in relation to the skill aspect manipulated in random practice, with the practice varying the perceptivemotor aspect being more difficult than the practice varying the motor aspect, and with the practice varying the motor aspect being more difficult than the practice varying the perceptive aspect and (b) it seems to have a relation of specificity between the ability of adapting to the perceptive perturbation and the skill aspect manipulated in random practice End-state comfort, minimal manipulation, and precision effects in the overturned glass task Fischman, Mark G.; Laura L. Whitaker, Auburn University
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Recent research suggests that actors desire to minimize awkward hand/arm postures at the end of object manipulation tasks, rather than the beginning. This phenomenon, the end-state comfort effect, acts to constrain the degrees-of-freedom problem in movement planning. However, Fischman and Kilborn (2006, NASPSPA) showed that there are situations when end-state comfort is rejected in favor of a “minimal manipulation” strategy. Their participants picked up a drinking glass half-filled with water, poured it into a cup, and then placed the glass upside down on a shelf overhead. Over 50% of their participants completed the task in an awkward thumb-down posture, thus violating end-state comfort. To complete the task with a comfortable thumb-up posture, participants would have to either switch the glass to their other hand, or put it down and pick it up again. Either choice requires an extra manipulation. Our experiment extended Fischman and Kilborn’s (2006) research by adding an element of precision to their task. Thirty undergraduates performed a single trial of two conditions. The first was identical to Fischman and Kilborn (2006) in which the empty glass had to simply be placed on an overhead shelf. The second condition added a precision requirement by placing two overturned glasses side-by-side on the shelf, but with enough space so that the manipulated glass could just fit between them. We predicted that the precision condition would cause participants to either switch the glass to their other hand, or put it down and pick it up again in order to achieve a comfortable end-state. Results were identical for both conditions: 18 participants (60%) completed the tasks with the awkward thumb-down posture. In the precision condition, only one participant achieved a comfortable thumb-up posture by switching the glass to his other hand. No one put the glass down and then picked it up. Taken together, a precision account of the end-state comfort effect was not supported, but a minimal manipulation hypothesis may still be a viable account for anticipatory planning behavior. Effect of extrinsic and intrinsic information on the planning of reaching movements Freitas, Sandra M.S.F.; University of Delaware; Nadia F. Marconi, Centro Universitário Nove de Julho; Gil L. Almeida, University of Ribeirão Preto Invariant characteristics of the end-effector (e.g., similar linear velocity profile and quasi straight-line hand path) suggest that the central nervous system (CNS) uses spatial information of the target (extrinsic parameter) to plan and control reaching movements. In this study, we investigated if these invariances on the extrinsic level are exhibited when information of the target location is not available during reaching movements (i.e., when reaching a specific joint angle is required). Eight participants were instructed to either (a) reach a spatial target (extrinsic task) or (b) extend the elbow to a specific angle (intrinsic task) and return to the initial position as fast and accurate as possible using movements of elbow and shoulder joints. The linear fingertip and angular shoulder and elbow trajectories were analyzed. Variable error of the fingertip position (extrinsic level), as well as shoulder and elbow angular position (intrinsic level) were assessed in four landmarks of the movements defined by the instant of (1) peak acceleration; (2) peak velocity; (3) movement reversal; and (4) return to the initial position. Kinematic characteristics of movements (fingertip linear displacement and velocity, and elbow and shoulder angular displacement) were similar in both extrinsic and intrinsic tasks. However, smaller fingertip variable errors at the time of peak velocity and movement reversal were observed in extrinsic as compared to intrinsic task. Variable errors of the elbow and shoulder angular position were also smaller when performing extrinsic as compared to intrinsic task. These results suggest that CNS uses extrinsic information
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to plan and control reaching movements independent if explicit spatial information of the target location is available. Emotion and sustained force control: The impact of target force level Gamble, Kelly M.; Stephen A. Coombes, James H. Cauraugh, Christopher M. Janelle; University of Florida Previous research suggests that the impact of emotion on force control may be modulated by the magnitude of the required target force. For instance, although highly arousing unpleasant states increase the variability of a precision pinch grip task at low target force levels 0.05). The audio RT for the single task condition remained stable across days (p = 0.3), indicating that the reduction in dual-task cost could not be explained by changes in audio RT (secondary task). Our results suggest that the audio-vocal dual-task paradigm is a feasible technique to assess attentional demands over practice and learning of a discrete arm movement. Are you sure you heard that right? Gonzalez, David A.; Thea O. Rotteau, Ranil Sonnadara, McMaster University; Steve Hansen, Liverpool John Moores University; James Burkitt, Kristina Gruevski, Alicia D’Amore, James Lyons; McMaster University Auditory cues are often used as “go” signals for tasks that require a response from participants, but the effect of the acoustic properties of these signals on the actions that they initiate is not often considered. Lyons et al. (2005) showed that movement planning was facilitated when compatible space and frequency mappings were used. Specifically, this study showed
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that reaction times were faster when participants responded to a high pitch by pressing the button in the right hemifield as compared with a button in the left hemifield. A follow up study using free-field presentation of tones revealed that perceived pitch-biased movements in the vertical, but not the horizontal plane (Gonzalez et al., 2007). We hypothesize that this result is caused by competition between spatial maps generated by implied pitch locations and the actual speaker locations. In other words, we suggest that perhaps perceived pitch has inherent spatial properties. We examine this in the present experiment by binaurally presenting the same set of tones over headphones at a central location (i.e., an identical stimulus is presented to both ears at the same time) and asking participants to identify the location from which they perceive the tone to be originating. Responses were restricted to a single dimension (vertical or horizontal) at a time. Results showed that in the absence of accurate spatial cues, participants order the tones in a systematic fashion with lower frequency tones being placed lower or farther to the left than higher frequency tones. These results, although preliminary, support our hypothesis that perceived pitch may indeed have inherent spatial properties, and that these spatial properties may affect movement planning and execution. The anticipatory nature of expert pattern perception Gorman, Adam D.; Australian Institute of Sport; Bruce Abernethy, University of Hong Kong and University of Queensland; Damian Farrow, Australian Institute of Sport The visual system has been shown to possess the capability to predict forthcoming events by adding information that has not yet been perceived, but is nonetheless likely to occur (Didierjean & Marmèche, 2005). For example, when participants are briefly shown a photograph of a moving object, and then asked to specify the object’s location after the photograph has been removed, the object is invariably misplaced and deemed to be further along its trajectory than that which had actually been shown (Futterweit & Beilin, 1994). This extrapolation of the temporal features is typically referred to as representational momentum (Intraub, 2002). Didierjean & Marmèche have shown that this phenomenon also occurs in a sporting context and may be mediated by an individual’s level of expertise. The present study replicated that of Didierjean & Marmèche but further extended it by comparing schematic images, static slides, and dynamic videos, which were all extracted from an actual basketball game. Participants were required to differentiate between pairs of patterns with some patterns presented in the normal order in which they would occur in a game, and some presented in the reverse order. Based on previous research, it was predicted that the experts would anticipate the next likely stage of play and encode the patterns as an anticipatory trace, thus making it difficult to differentiate between patterns presented in the normal chronological order of a game, compared to those shown in the reverse order. When the results were collapsed across all three display types, the decrement in expert performance for patterns presented in chronological order was not evident. In addition, despite the increased ecological validity, all participants found the dynamic video stimuli to be significantly more difficult to differentiate than the schematics and static slides. Even though the representational momentum effect has previously been shown to exist with schematic images, the effect appears to be somewhat different when the test stimuli are more representative of the natural setting. Anti- and pro-pointing elicit visual field specific end-point bias Gradkowski, Ashlee; Alycia Underhill, Bryan Godbolt, Matthew Heath; University of Western Ontario
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A myriad of studies have shown that the ability to “look” at the mirror symmetrical location of a target (so-called anti-saccade) is mediated by top-down inhibition of the cortical and subcortical mechanisms supporting pro-saccades. Interestingly, however, a paucity of work has examined the behavioral antecedents characterizing pointing movements to a mirror symmetrical target location (so-called anti-pointing). As such, the present work was designed to determine if anti-pointing movements elicit a pattern of end-point bias characterizing top-down perceptual processes. To accomplish that objective, participants completed anti- and pro-pointing responses to horizontal targets presented left and right of a common midline start location (i.e., responses in left and right visual fields) and across visual conditions wherein target location was continuously visible or occluded at, or prior to, response cuing. In line with the saccade literature, anti-pointing movements yielded longer response latencies than pro-pointing counterparts: a result suggesting increased top-down processing for response specification in a direction opposite a real target location. Most interestingly, anti- and pro-pointing responses in left and right visual fields were characterized by a differential pattern of end-point bias, and this bias was not modulated by the different visual conditions used here. Specifically, pro-pointing movements yielded comparable (and robust) end-point accuracy in left and right visual fields whereas anti-pointing movements produced overshooting and undershooting of target location in respective left and right visual fields. These results suggest a perceptual representation of target location guides anti-pointing responses and that such a representation is sensitive to a hemispatial bias in peripersonal space. Put another way, we propose that the relative position of a mirror symmetrical target for pointing responses in left and right visual space is associated with a respective over- and underestimation of absolute movement distance. Supported by NSERC. Kinematic analysis of goal-directed aims made against early and late perturbations: An investigation of the relative influence of two online control processes Grierson, Lawrence E.; McMaster University; Digby Elliott, McMaster University and Liverpool John Moores University Examination of goal-directed movements has evidenced 2 processes of visually regulated online control: early trajectory control that operates to make continuous movement adjustments on the basis of limb velocity comparisons to internally generated models of the expected limb velocity, and late trajectory control that uses allocentric information about the limb and target positions to make movement corrections in the latter movement portions. The results of experiments using illusory perturbations indicated that the efforts exerted by the 2 systems had an additive influence on movement outcome and led to the conclusion that because they depend on different information they are relatively independent of one another. To expand the investigation into the independence of 2 control processes, 3 experiments were conducted in which actual perturbations to the aiming limb dynamics and the tasks demands are introduced. Compressed air expulsed through a stylus, in the direction of, or opposite to, that of the movement, has been used to impact limb velocity and elicit evidence of early control. Manipulating target location has been effective in gleaning evidence of the discrete control associated with late trajectory evaluations of target and limb position. To investigate the relative influence of these 2 types of online control, kinematic analyses of the performer’s aiming movements were conducted. Following movement initiation, perturbations to the performer’s limb, the environment, or both were introduced. The results of the compressed air-only and moving target-only conditions replicated the previous evidence of
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early and late control, respectively. Interestingly, movement accuracy measures yielded an interactive effect of the two perturbations when presented in tandem. It was concluded that the perturbations prompted parallel operation of the two control processes. Multiple bottlenecks in dual-task processing Guan, Hongwei; Ithaca College; David M. Koceja, Indiana University Since Welford (1952) initially proposed the single-channel theory to explain the psychological refractory period (PRP) effect that the reaction time (RT) to a second of two stimuli in close succession is lengthened and the delay increases as the time between the two stimuli (stimulus onset asynchrony, SOA) decreases. A bottleneck in information processing is believed to cause the PRP effect. However, different models are proposed and they disagree concerning the locus of the bottleneck and whether multiple bottlenecks exist (De Jong, 1993; Pashler, 1994). Purpose: The purpose of this study was to identify possible neurological as well as the cognitive factors in a PRP model by using the fractionated reaction time technique with electromyography (EMG). This technique allows for the examination of both central and peripheral components in a PRP paradigm. Methods: Twenty right-hand dominant college students were tested for their visual-manual reaction time. A choice RT task followed by a choice RT task utilizing either forearm pronation or supination movements as the PRP condition was used. Based on the EMG activity of the pronator teres and biceps brachii, RT and its fractionated components, premotor time (PMT) and motor time (MT), were measured for each movement. Participants were randomly assigned to two groups depending on movement order. A 2 (Gender) × 2 (Group) × 5 (SOA) × 2 (Response) ANOVA was used for data analysis. Results: Significant PRP effects were observed for RT, PMT, as well as MT. In addition, the MT for both responses demonstrated the PRP profile. Conclusion: The significant PRP effect found for PMT and MT in the choice-choice dual task situation support the existence of multiple bottlenecks in dual task processing. The significant PRP effects for MT for both responses in this condition indicated that motor time contributed to the PRP effect and the relationship between Response 1 and Response 2 may be more interactive than originally hypothesized (only the first response affects the second one). Locomotion efficiency is influenced by optical flow Guérin, Perrine; University of Paris XI and University Montpellier 1; Benoit G. Bardy, University Montpellier 1 In two experiments, we evaluated the role of optical flow (OF) in stabilizing kinematics and energetic parameters of locomotion. Participants were instructed to walk or to run on a treadmill in a virtual environment. The aim of the first study (N = 7) was to evaluate the role of OF during unstable locomotion: walk (W) or run (R) at preferred transition speed (PTS). Four conditions of OF were tested: static flow (0%), OF velocity consistent with locomotion speed (100%), OF velocity twice faster (200%), or twice slower (50%) than locomotion speed. In the second experiment (N = 8), we tested in two sessions the efficiency and the stabilizing influence of three OF conditions during walking at 110% PTS: static flow (S); natural flow, i.e., opposite to locomotion (N); and reverse, non-natural flow (nN). We measured both the energy expenditure (EE - ZAN 680) and the kinematics of posture and gait (Oxford Metrics VICON, 50 Hz). In Experiment 1, the 200% condition exhibited the most variable (stride length, relative phase, vertical motion of the center of mass) but efficient locomotion. Significant correlations between EE and SD of vertical motion of the
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center of mass (r = 0.45), and between EE and SD of relative phase (r = 0.36) suggested that variability in the kinematics patterns reflected functional adaptations. Walking at 110% PTS (Experiment 2) in natural optical flow reduced EE compared to a non-natural flow condition, although this reduction vanished over time with practice (session effect). In conclusion, the co-occurrence of efficiency and (adaptive) locomotor variability suggests that optical flow encourages the exploration and stabilization of the most economic behavior. These results emphases the mutual dependency of the visual system, the locomotor system and the cardiorespiratory system. They also have practical implications in the world of fitness. Characteristic of elite visual information pick-up in fencing Hagemann, Norbert; Bernd Strauss, Jörg Schorer, Rouwen Cañal-Bruland, Simone Lotz; University of Münster Perceptual skills are a critical factor for experts’ superior performance, especially in interactive sports. In the present study we used an expert-novice paradigm to examine the spatiotemporal course of visual information pick-up of fencers attacking strokes. A combination of the progressive temporal (3 levels: 40 ms, 80 ms, 120 ms before contract) and spatial occlusion (4 areas: head, trunk, legs, feet) paradigms was applied. To validate the revealed sources of information we added a color cueing approach and recorded the athlete’s eye movements (EyeLink II). Expert fencers (n = 14, international level), intermediates (n = 9, regional level), and novices (n = 32, sport students) had to predict the direction of 360 attacking strokes on a computer screen by indicating the target area via mouse click (5 areas). Mean response accuracy was calculated. The 3 (group) × 4 (occluded areas) × 3 (temporal occlusion condition) × 2 (occlusion vs. cueing) repeated-measures ANOVA revealed highly significant main effects for the temporal occlusion condition, expertise level, occluded region, and occlusion technique (occlusion vs. cueing) (all p < . 05). Experts attain the best accuracy scores and suffer most if the trunk region is occluded. The interaction Expertise Level × Occluded Region × Temporal Occlusion condition showed that the groups rely on different cue sources during the spatiotemporal course of visual information pick-up (e.g., occluding the trunk region impairs experts’ accuracy from the very beginning). The analysis of the eye movement analyses underlines the importance of this central region. Instead, cueing of the peripheral information areas (e.g., feet, head) does not improve the prediction performance. In conclusion, the study reveals that expert fencers have superior perceptual skills in comparison to less-skilled fencers. The use of early information (e.g., trunk) is assumed to be picked-up by foveal and para-foveal information processing. External focus of attention improves running economy Hagemann, Norbert; Bernd Strauss, Linda Schücker, University of Münster; Klaus Völker, University Hospital of Münster This is the first study to examine whether the focus of attention can influence oxygen consumption at a set running speed. Economic running movements (i.e., a low oxygen intake at a given intensity) are very important for top-level athletic performance. Running economy is influenced by a variety of factors, and these may also include the focus of attention, which plays a major role in the motor system in general. One frequently replicated finding in research on the motor system is that focusing attention on carrying out well-learned motor skills (an internal focus) leads to a deterioration in performance compared with focusing attention externally (e.g., on the effects of the movement). This experimental study transfers
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this finding to the field of physiology and endurance sport. Trained runners had to focus their attention on three different aspects while running on a treadmill. For 10 min, they had to concentrate on the running movement; another 10 min, on breathing; and another 10 min, on their surroundings. Dependent measures were oxygen consumption, blood lactate concentration, and heart rate. Results showed an increased running economy in the external focus condition, and that an internal focus (on either the movement or breathing) disrupted subconscious or automatic control processes, F(2, 46) = 29.91, p < .001, η² = .56. In line with research on the motor system, research on endurance sport reveals a superiority of focusing attention externally when oxygen consumption is taken as a physiological performance measure. This finding is particularly relevant in endurance sport because it can be used to instruct athletes regarding where to focus their attention during performance. Balance and postural control in young and old resistance training and sedentary adults Haibach, Pamela S.; Greg Norton, SUNY Brockport An experiment was conducted to examine the effects of resistance training and age upon balance and postural control. Sixty participants (50% male) aged 18–28 years (young group) and 55–75 years (old group) were tested on a Biodex Balance System. Participants were tested on four conditions, stability for both feet, left, and right foot, and dynamic limits of stability. During the stability conditions, participants were instructed to maintain their center of pressure within a specified region by viewing a display of their center of pressure on a visual target while the base of support became progressively less stable for a period of 20 s. The stability index was calculated by the overall, anteroposterior, and mediolateral motion and the deviation from the central position of the base of support. A lower score indicated better balance. During the dynamic limits of stability condition, participants were presented with various targets on the screen (2 degrees anteriorly and 4 degrees posteriorly). The object of the task was to control the position of the body to move a cursor on the screen which corresponded with the center of pressure to the various targets on the screen and hold the position of the cursor within the target for 1 s each. The time to complete the task and the control of the movements to each direction (forward [F], backward [B], right [R], left [L], F-R, F-L, B-R, B-L) was recorded. A dynamic comparison was also calculated for the right and left feet. Significant effects were found for age, activity levels, and gender. Females gained a greater benefit in balance and postural control from regular resistance training than males. Both young and old adults showed improved balance and control from regular resistance training; however, older adults gained a greater advantage from the effects of resistance training on balance and postural control than the young adults. In conclusion, older adults who engage in overall body resistance training can improve their balance and postural control, decreasing their risk of incurring a fall. Executing corrections: Responses to changes in target direction and amplitude Hansen, Steve D.; Digby Elliott, Liverpool John Moores University Manual trajectory corrections in response to changes in direction and amplitude of targets during rapid aiming were examined. Target locations could change in direction, amplitude, or both direction and amplitude relative to the starting position presented at movement initiation. A large proportion of perturbation trials (75%) were employed to investigate the visual-motor behavior of the participants under conditions where attending to the visual context during
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movement execution was more beneficial than the information provided before movement initiation. The importance of visual information gathered at different points during the rapid movements for the control of amplitude and direction was investigated by examining trialto-trial spatial variability throughout the movement trajectory. Movement time increased when the target became more distal or moved into contralateral space when target amplitude and direction were manipulated in isolation. Trajectory variability analyses indicated reductions in variability at 60–72% of the movement when the target became more proximal or moved into ipsilateral space. Further analyses of the temporal structure of the movements, 3-D variability, and other kinematic variables revealed sex differences in movement execution when both amplitude and direction were manipulated. Female participants displayed higher movement variability in the early portions of their movements (36–48%) and spent less time decelerating their movements than males. In comparison, male participants were more variable late in the movement trajectory (60–72%) and maintained consistent timing between conditions. Sex differences in this context highlight the importance of including subject variables while investigating visual-motor control. In general, the results revealed that the processes and strategies involved in goal-directed aiming depend on the characteristics of the individual performer. Current models of visual-motor regulation might require re-visitation in light of the latter results. Age-related adaptability of postural control as assessed by recurrence quantification analysis Hasson, Christopher J., Richard E.A. Van Emmerik, Graham E. Caldwell, University of Massachusetts–Amherst Age-related declines in postural stability may be due to less flexible control. If degrees of freedom are reduced by mechanical constraints, a flexible system would be expected to change its control strategy. Such strategies can be quantified using recurrence quantification analysis (RQA) of the ground reaction force center of pressure (CoP) movement. In this study we used RQA to examine CoP motion for both freestanding and constrained quiet stance in healthy young and older adults to assess the adaptability of their postural control systems. Twelve young (Y: 27 ± 3 years) and nine older subjects (O: 71 ± 5 years) were asked to stand as still as possible on a force plate for 30 s under freestanding and constrained conditions. In the constrained condition a lightweight wooden backboard restricted motion to the sagittal plane about the ankle joint. The RQA was performed on the raw anterior-posterior CoP movement sampled at 100 Hz. Computed RQA variables assessed system repeatability (%determinism; %DET), complexity (entropy; ENT), and intermittency (%laminarity; %LAM). Paired t tests were used to evaluate changes in the RQA variables as a function of postural condition (free vs. constrained) for young and older subjects. Across postural conditions, the %DET (Y: 92.5%; O: 96.4%) and %LAM (Y: 94.8%; O: 97.8%) were higher in the older subjects, whereas ENT was about the same (Y: 5.6; O: 5.9 bits). In the younger subjects, all three RQA variables increased with the backboard constraint compared to freestanding (%DET 3.2%, p = .014; ENT 0.56 bits, p = .010; %LAM 2.4%, p = .019). In contrast, little change was seen in the older subjects (%DET 0.9%, p = .440; ENT 0.05 bits, p = .867; %LAM 0.7%, p = .378). These results are in agreement with earlier observations that older individuals do not change upper body coordination between constrained and freestanding postural tasks (Gariepy et al., 2008). Together, these data suggest that the postural control system of older adults is less adaptable, using a similar control strategy for both free and constrained standing. Funding: NIH R03AG026281.
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Using time-to-contact to predict stepping behavior after postural perturbations in older adults Hasson, Christopher J.; Graham E. Caldwell, Richard E.A. Van Emmerik; University of Massachusetts–Amherst The center of mass (CoM) time-to-contact (TtC) is a spatiotemporal measure that the postural control system may use to predict future instability. Previously we described a quadratic relation between the minimum CoM TtC and the magnitude of upper-body postural perturbations in healthy young adults (Hasson et al., in review). The minimum vertex of the quadratic was predictive of the transition from a stationary support base to a stepping behavior. The purpose of this study was to determine if minimum TtC information could also predict stepping behavior in response to perturbations in older adults. Twelve young (Y: 27 ± 3 years) and nine old (O: 71 ± 5 years) subjects were strapped to a lightweight wooden backboard and given a series of sequentially increasing upper body perturbations using a spring-loaded 15-kg pendulum. Subjects were to resist the perturbation, stepping only when necessary to prevent a fall. The postural challenge was computed as the peak pendulum velocity divided by subject mass. The instantaneous TtC was computed using CoM position (relative to support boundary), velocity, and acceleration, with the minimum TtC selected for further analysis. For both age groups, quadratic equations fit the minimum TtC vs. postural challenge relation well (R2: Y = 0.97 ± 0.25; O = 0.96 ± 0.27); the vertices of the equations accurately estimated the challenge level (error: Y = 0.17 ±0.13; O = 0.11 ± 0.07 deg/s/kg) and the minimum TtC (error: Y = 7 ± 3; O = 9 ± 14 ms) in the trials that elicited stepping behavior. The older adults transitioned to a stepping response at significantly lower postural challenge levels compared to younger subjects (1.1 ± 0.3 vs. 1.8 ± 0.2 deg/s/kg). For a given challenge level, the older adults tended to have a shorter minimum TtC, largely due to higher peak CoM acceleration. The minimum TtC occurred ~110 ms after perturbation onset in both groups. This short latency suggests that the different group responses may be due to differences in pre-perturbation musculoskeletal states (e.g., plantar flexor and/or total body stiffness). Funding: NIH R03AG026281. Eye movements during observational practice Hayes, Spencer J.; Liverpool John Moores University; Matthew Timmis, University of Bradford; Simon J. Bennett, Liverpool John Moores University In two experiments we examined whether eye movements during observational practice (OP) are involved in the formation of a representation used to control an upper limb aiming movement. This question was examined using a fixation paradigm where eye movements were restricted when viewing movement-related information from a visual display. In Experiment 1, four groups observation (OBS; fixation, FIX; physical practice, PP; control, CON) performed a pretest, physical practice/observation phase, and posttest. During the physical practice phase, a PP participant practiced an upper limb aiming movement; the visual feedback on the limb as it moved through a sequence of targets was presented on a monitor. The task required a cursor to be oriented through a sequence of 3 targets in accord with three time goals (TG): 800 ms, 1,000 ms, 1,200 ms. An OBS and FIX participant observed the PP participant’s performance and KR on separate, but linked, monitors. The OBS participant was free to pursue the cursor whereas the FIX participant was instructed to fixate on a central target. Analysis of absolute constant error (ACE) and variable error (VE) revealed an interaction at each TG. The OBS, PP, and FIX groups became more accurate
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and consistent than the CON group across practice, indicating that eye movements are not a prerequisite in forming a representation during OP. In a second experiment, four additional groups performed a similar task but with a smaller target diameter in order to increase difficulty. ACE and VE data for 1,000 ms and 1,200 ms TGs indicated that all groups showed an improvement across practice. At the 800 ms TG, however, only the PP group improved across practice. These data confirm the finding that eye movements during OP do not afford any advantage in latter task performance, and also indicate that as task difficulty increases the ability to acquire motor skills through OP is impaired relative to PP. Complexity effects or concurrence costs for non-speeded secondary tasks Hendrick, Joy L.; SUNY Cortland Recent evidence has brought to question what concurrence costs are involved in conducting non-speeded secondary tasks after a quick reaction (Fischman, McAlister & Kinley, 2005). It was the purpose of this study to further examine this issue by expanding their protocol to include reaction time (RT) tasks with greater stimulus complexity. RTs under three conditions were compared: Control simple RT, 2-choice go/no-go, and 2-choice go/no-go followed by a non-speeded secondary task. Participants (N = 28) were tested on three days with 30 trials per condition with the order of conditions randomly varied. In response to a visual stimulus, they were asked to move their dominant hand to a particular button, depending on the condition. In the secondary task condition, participants were asked to pick up a small object and then press a second response button at their leisure. They were instructed to wait at least 2 s after completing the primary RT task before initiating the secondary task. There was a significant condition effect on RT. Simple RT (M = 226.5 ms, SD = 21.2) was significantly faster than the go/no-go conditions with and without the secondary task (M = 344.4 ms, SD = 47.9, and M = 347.5 ms, SD = 51.5, respectively). Surprisingly, performing the secondary task had no influence on RT. Following data collection, participants were queried about their thought process during the secondary task condition to better understand how they approached the task. Interestingly, most participants adopted one of two strategies. The first involved a primary focus on the RT task while the second involved focusing on both tasks, which was inconsistent with the instructions. Data were further analyzed to compare the conditions based on the self-identified strategies. Although there was still no difference in RT whether conducting a secondary task or not, overall RT was faster for those who focused primarily on RT. These results provide evidence for the influence of speed-accuracy trade-off strategies on the concurrence costs in double stimulation tasks. Contributions of visual perception to the selection and performance of multifrequency ratios Hessler, Eric E.; Laura M. Gonzales, Polemnia G. Amazeen; Arizona State University Only a small number of frequency ratios between movement and breathing are performed naturally across a variety of exercises, including bicycling, rowing, running, walking, and wheelchair propulsion. The present study was designed to investigate whether perceptual limitations constrain the performance of different coordination patterns and, thus, limit the frequency ratios observed. Two experiments were conducted that focused on perceptual and motor constraints on frequency ratio coordination. In the first experiment, simulations of different frequency ratios were depicted as oscillating balls on a computer screen. Participants viewed pairs of frequency ratios and judged whether those ratios were the same or different.
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The ratios presented were selected from the Farey tree, a mathematical model whose levels correspond to performance stability in the aforementioned exercises. The probability of confusing ratios in each pair was calculated and then submitted to multidimensional scaling analysis (MDS). MDS identified Farey tree distance as a prominent dimension along which participants made their judgments. Specifically, ratios on the same level were more likely to be confused than ratios on more distant levels. In the second experiment, participants utilized different types of augmented feedback to perform frequency ratios between sagittal arm movement and breathing. Performance was most accurate with veridical feedback, which corresponded directly to participant’s movement and breathing patterns. In contrast, participants had difficulty differentiating among ratios with manipulated feedback, which specified only the magnitude and direction of error from the intended ratio. Therefore, the presence of additional perceptual information was beneficial to performance. The implication of these findings is that perceptual constraints on action guide the selection of motorrespiratory frequency ratios naturally performed during exercise. Trait anxiety modulates the impact of emotional state on motor planning Higgins, Torrance J.; Kelly M. Gamble, Steve A. Coombes, Christopher M. Janelle; University of Florida A key function of emotion is preparation for action. Previous research has demonstrated that reaction time and sustained force production are affected by changes in emotional valence. The purpose of the present study was to determine how individual differences in trait anxiety interact with emotional state to modulate motor planning timing and accuracy of a goaldirected ballistic pinch grip task. Subjects reporting high (n = 30) and low (n = 27) trait anxiety scores on the STAI completed a practice session followed by 30 experimental trials. During each experimental trial, subjects viewed an emotional image (adventure, erotica, attack, mutilation, or neutral). At image offset, subjects performed a pinch grip at either 10% or 35% of their maximum voluntary contraction (MVC) as quickly and accurately as possible. Reaction time (RT), time to peak force, and root mean square error (RMSE) were calculated for each trial. Regardless of trait anxiety and target force level, subjects demonstrated faster RTs in response to attack images compared to erotica and adventure images. At the 10% target force level, peak force was reached more rapidly following attack images relative to all others except mutilation, and following mutilation compared to adventure images. At the 35% target force level, peak force was reached more rapidly in response to neutral images compared to all other valence categories except attack, and was delayed following mutilation images relative to all others except adventure images. Examination of RMSE scores at 35% target force indicated that high trait anxious subjects exhibited attenuated error after viewing mutilation images compared to erotica and neutral images, whereas the low anxious subjects demonstrated greater error while viewing mutilation images relative to erotica and neutral images. Corroborating previous research, transient unpleasant emotional states were linked with significantly faster ballistic movements. Potential underlying neurobiological mechanisms and future research directions are discussed. Speed-accuracy trade-offs in people with Down syndrome Hodges, Nicola J.; Melanie Y. Lam, University of British Columbia; Naznin Virji-Babul, Down Syndrome Research Foundation; Mark L. Latash, Pennsylvania State University
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The purpose of this study was to analyze the speed-accuracy trade-off in the performance of persons with Down syndrome (DS) in the task of tapping alternately two spatial targets as accurately and quickly as possible. Movement time (MT) scaled linearly with the logtransformed ratio of movement amplitude to target size (index of difficulty, ID) in both DS and typically developing participants. Persons with DS performed the task considerably slower than typically developing individuals. Linear regression analysis on MT and ID showed a nearly twofold higher regression coefficient and a nearly threefold larger intercept value in the DS group. The dwell time on a target was much longer in DS persons. It scaled with ID in about the same percentage of DS and TD participants. The results suggest that persons with DS show slowness related to two factors, presence of an explicit target and its size. We conclude that mechanisms of motor control are not changed qualitatively in DS, they only differ in scaling of parameters with task difficulty. Reducing the scalability of visual knowledge of results to facilitate changes in coordination through demonstration Horn, Robert R.; Sofia V. Capparelli, Montclair State University Past research indicates that the availability of visual knowledge of results hinders participants’ attempts to replicate a model’s demonstrated technique. We tested the hypothesis that reducing the extent to which visual feedback was scalable for action would lead to better learning of the model’s technique than learning with fully scalable feedback. Two groups of novice participants learned a rugby scrum half pass. Both groups performed a pretest with minimal verbal instructions, and then observed a video model perform the skill 10 times. The control group then performed three batches of 10 acquisition trials, aiming the ball at a cross-hair on a wall 6.4 m away. The experimental group also performed three batches of 10 trials, but aimed to hit large tarps that were scaled to the projected distance of the ball, and decreased in size in each progressive period (50%, 37.5%, and 25% of the distance). Composite form scores were derived from three upper and three lower body components, each with five performance levels (test–retest r = 0.95). For intralimb and interlimb coordination, three Vicon MX-3 cameras collected data at 240 Hz. Radial error and variable error outcomes scores were collected at the end of each batch of ten trials. For composite form scores, ANOVA indicated main effects for test period and group, and showed a Test Period × Group interaction (all ps < 0.01). Both groups improved their form from the pretest to all subsequent test periods. However, the experimental group demonstrated superior form to the control group, most notably in the first and last acquisition periods, and in the delayed retention test. Superior learning by the experimental group is also shown in angle-angle relative motion plots. There were no main effects for radial error and variable error scores. The results support the suggestion that for tasks requiring a specific technique coupled with accurate outcomes, learning through demonstration may be facilitated by minimizing usable visual feedback in the early stages of learning. Effects of target goal and obstacle arrangement congruency on a bimanual grasping and placing task Hughes, Charmayne M.; Purdue University; Elizabeth A. Franz, University of Otago Previous research has demonstrated that individuals take longer to plan and enact bimanual responses compared with unimanual responses. This finding is termed the bimanual cost,
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and is supported by other studies utilizing multifarious manipulanda and movement goals (Di Stefano et al., 1980; Kerr et al., 1963; Ohtsuki, 1981). We examined bimanual cost during initiation and movement time (IT and MT respectively) using a unimanual and bimanual grasping and placing task with manipulations on target goals and obstacle arrangement. A corollary purpose was to investigate the effect of the same manipulations on temporal coupling variables. Consistent with simple RT findings (Shen & Franz, 2005; Hughes & Franz, 2007), our data reveal that unimanual conditions were considerably faster than bimanual conditions with identical task requirements. Additionally, incongruent bimanual tasks yield considerably slower ITs and MTs than conditions with identical goals. However, the presence of a physical obstacle affects only MT. We attribute this finding to two costs: the first cost occurring from a form of callosally mediated interhemispheric communication, and the second reflects costs in the conceptualizing, planning, and completion of the goal-related bimanual task. Analysis of bimanual coupling variables’ signed and absolute differences during IT reveal that when both the obstacle arrangement and target goals were identical for the two hands, the onset of movement was more closely coupled on average than when such congruence was not present. During MT, there was no clear pattern as to which hand’s MT was generally longer or shorter, but only that they were on average, more different from one another. Taken together, the data indicate that goal congruency is the primary factor in uncoupling the movement onset time IT, as well as in making MT more dissimilar. Balance in multiple sclerosis patients is affected by resistance training Huisinga, Jessie M.; University of Nebraska at Omaha; Mary L. Filipi, University of Nebraska Medical Center; Nicholas Stergiou, University of Nebraska at Omaha and University of Nebraska Medical Center Multiple Sclerosis (MS) is a progressive neurological disease affecting over 400,000 Americans (Crenshaw et al., 2006). Symptoms may include sensory disturbances, optic neuropathy, trunk and limb parasthesias, limb weakness, gait ataxia, and severe fatigue (Noseworthy et al., 2000). Lack of measures to objectively quantify movement impairments in MS patients is a problem for patients and clinicians; therefore, a protocol is necessary to distinguish between clinical relapses and transient worsening of symptoms. Center-of-pressure measures may provide the necessary precision, whereas use of linear and nonlinear data analysis to determine system variability may provide the sensitivity to define differences in balance capability due to relapse or treatment interventions. Standing balance of 6 patients with MS was assessed during two standing conditions (eyes open and eyes closed) on a Kistler forceplate. Patients were assessed pre- and postinvolvement in a supervised, 3-month resistance training intervention. Center of pressure was used to calculate root mean squared (RMS) linear measure and Lyapunov exponent (LyE) nonlinear measure. A 2 × 2 ANOVA was used to determine the effects of the intervention and standing condition. The RMS showed no differences due to standing conditions or intervention; LyE showed a significant effect of intervention, with decreased values postintervention, whereas standing condition showed not significant effects. However, there was a significant interaction between intervention and standing condition. The lack of change in the RMS values could indicate no change in the amount of variability in the system due to the intervention. However, the decrease in LyE values indicates a decrease in divergence of the sway path of MS patients following the intervention and possibly less randomness in their movements. Consideration of the data analysis methods could greatly affect the ability to sufficiently measure changes in postural control in MS patients due to treatment or relapse. This work was supported by the MARS Foundation.
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Distinct timing mechanisms produce distinct speed-accuracy trade-offs Huys, Raoul; Laure Fernandez, Reinoud Bootsma, Université de la Méditerranée; Viktor Jirsa, CNRS and Université de la Méditerranée The inverse relation between movement speed and accuracy has attracted researchers’ interest over more than a century. The most renowned formalization of this so-called speedaccuracy trade-off is known as Fitts’s law, which states that movement time is a linear function of task difficulty, i.e., MT = a + b ID, where MT denotes movement time, a and b are constants, and ID (index of difficulty) equals log2(2D/W), where D and W represent target distance and width, respectively. Previously, it has been suggested that fixed point dynamics and limit cycle dynamics are implemented in (the repetitive version of) Fitts’s task in an ID-dependent fashion. This suggestion, however, was based on kinematic analyses, which are limited in uncovering the dynamics underlying movements. We examined Fitts’s task from the perspective that two distinct timing mechanisms that are associated with discrete and rhythmic movements may be implemented in its execution. Ten participants performed Fitts’s task under twelve ID conditions (ranging from 2.5 to 6.9) that were realized by varying target widths under constant amplitude. We reconstructed and analyzed the vector fields underlying the participants’ movements. Hints were found suggesting that limit cycle dynamics were implemented under low IDs whereas fixed point dynamics were implemented under high IDs. In addition, using linear regression we found evidence that distinct speed-accuracy trade-offs are associated with distinct timing mechanisms. These findings not only indicate that information constraints the selection of (dynamical) timing mechanisms, but also show that the relation between information and movement speed depends on the timing mechanism utilized. Visual search strategies and expertise of touch football players while observing a scene-monitor video film Ishibashi, Yukimasa; Tomohisa Nagano, Takaaki Kato, Yuji Ohgi; Keio University The purpose of this study was to compare the visual search behavior of expert touch football players and novices while they observe a scene-monitor video film, wherein the performers’ actual vision can be assessed. In touch football, one of the most effective strategies for successful offensive play is passing play. This play mostly occurs when a quarterback (QB) player attempts to deliver the ball to teammates while gaining territory in the field. A QB player has to possess not only physical strength but also the ability to make decisions on passing the ball to the target player immediately and accurately, due to the successful offensive play. This decision-making skill depends on the acquisition of visual information on temporal and spatial factors from a constantly changing environment. Therefore, by using temporal and spatial occlusion approaches, we assessed the visual search behavior with respect to responding accuracy and time where 12 experts and 12 novices made correct decisions to make a pass to the target player while observing the scene-monitor video film. Visual search behaviors were obtained using an eye movement registration system (FreeView, T.K.K. 2920, Takei Scientific Instruments Co., Japan). A significant difference in both response accuracy and time was observed between the experts and novices in terms of both temporal and spatial occlusion approaches. The different visual search strategies between experts and novices were also found. The following three were most notably findings. First, the distribution of the experts viewing points was smaller than that of the novices viewing points. Second, the experts did not move their gaze to the target player according to priority. Third, the experts fixated their gaze between target players. These results indicated that experts immediately
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utilized the properties of the ambient vision system for receiving visual information broadly within a small gaze area. Lastly, the proposed training system that made use of a scenemonitor video film with temporal and spatial occlusion approaches was discussed. Effects of motoric rehearsal on selection of viewing angle of model demonstration Ishikura, Tadao; Doshisha University The purpose of this study was to examine the relationship between the selection of the viewing angle and the timing of motoric rehearsal simultaneous / delayed reproduction in golf swing observations. Ninety-one participants, who took part in the golf class at university and were novices at golf, were observed under one of three conditions; observation only (OO), observation with simultaneous reproduction (OWR), and reproduction after observation (RAO). Participants were required the choice of a viewing angle from four angles, which was the front, the back, the left, and the right side of model, on the week 2nd pretest and on the 13th week posttest. The result showed the following: First, the 60% of participants chose to make the observation from the front of the model in both tests. Second, the motoric rehearsal conditions OWR and RAO rates of the back angle of the model were more than OO. Third, the RAO condition rates of the back angle were more than the other condition rates in pretest. Fourth, the choice rates of each condition tended to change from pretest to posttest. These results suggested that the pattern of the timing of motoric rehearsal and the practice experience affect the participant’s choice of viewing angle of the model. The relationships between perceived competence, intention to be physically active, physical education grade, and the fundamental movement skills within seventh grade students in Finnish physical education Jaakkola, Timo T.; Sami P. Kalaja, Ari A. Jutila, Petri P. Virtanen; University of Jyväskylä The aim of the study was to investigate the relationships between perceived competence, intention to be physically active in future, physical education grade, and the fundamental movement skills within seventh-grade students participating in Finnish physical education. The participants of the study were 152 Finnish seventh-grade students: 13-year-olds, 76 girls and 76 boys, involved in seven classes, and taught by four physical education teachers. All students were from the same school in Jyväskylä, which is a medium sized city in the Central Finland. Perceived competence and intention to be physically active in future were analyzed by self-report questionnaires, which have widely been used in Finnish physical activity and exercise motivation research. Additionally, the PE grade of last report was asked from the students. The leaping test was used to measure students’ locomotor skills. Balance skills were measured by using the flamingo standing test. Accuracy throwing test was used to analyze students’ manipulative skills. The tests of fundamental movement skills were adapted from existing motor and physical fitness test packages. The data was collected during one 90-min physical education class taught by the PE teacher of the class. Correlation coefficients were conducted in order to examine whether perceived competence, intention to be physically active, and PE grade were associated with the fundamental movement skills. The correlation coefficients indicated that balance and locomotor skills were positively associated with PE grade in both gender groups. The correlations between PE grade and manipulative skills were not significant. In the girls group the intention to be physically active in future was associated with balance skills, whereas in the boys group it correlated with locomotor skills. The perceived competence correlated with locomotor and
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balance skills. This finding existed in both gender groups. The perceived competence was not associated with manipulative skills. Experts do, experts see? Common coding versus perceptual experience in anticipation skill Jackson, Robin C.; University of Hong Kong; John van der Kamp, VU University Amsterdam; Bruce Abernethy, University of Hong Kong The expert’s superiority in anticipating an opponent’s intentions affords a crucial performance advantage over less-skilled individuals. The role of “perceptual experience” has been central in accounting for this expert advantage, yet the role of action has been conspicuously absent. The common coding hypothesis suggests that representations that allow one to perceive the intention of an action are the same as (or even identical to) representations that determine the actual production of an action. For example, evidence from neuroscience suggests that the “mirror” neuron network is activated both when actions are produced and when actions serving the same goal are observed. We conducted two experiments to test two predictions emanating from the common coding hypothesis. In Experiment 1, we examined whether the ability of tennis players to judge serve direction was moderated by the handedness of the server. Skilled and novice left- and right-handed players (N = 50) viewed video clips of serves from two high-skilled players (one left handed, one right handed), manipulated so that the footage from both players was presented in both left-handed and right-handed form. The results revealed that left-handed skilled participants were no better at predicting the direction of left-handed serves than right-handed serves. In Experiment 2, high-skilled badminton players (N = 20) attempted to judge the direction of shots played by either themselves, a teammate, or an unfamiliar player of equivalent skill, from full video and point-light displays. Overall, judgment accuracy was significantly better in the video than in the point-light format; however, there was no effect of player familiarity. Indeed, using a within-task criterion to compare the most and least successful anticipators, we found that the two groups were most clearly differentiated when viewing players other than themselves. The results indicate that the ability to produce goal-directed actions does not confer specific advantages beyond those attained through perceptual experience. Change in the complexity of low frequency postural dynamics with aging James, Eric G.; Pennsylvania State University; Lee Hong, Louisiana State University; Karl M. Newell, Pennsylvania State University The loss of complexity hypothesis holds that there is a general decrease in the complexity of physiological systems that occurs with aging. This hypothesis has been supported by observations of decreased complexity in the output of numerous physiological systems with aging, including standing postural sway. This study examined the loss of complexity hypothesis with aging in seated postural dynamics across several frequency bands of the center of pressure (COP) time series. Approximate entropy (ApEn) was used as a measure of the time-dependent complexity of the COP dynamics along the x- (mediolateral) and y- (anteroposterior) axes of motion within the 0–4 Hz, 4–8 Hz, 8–12 Hz, and 12–16 Hz frequency bands. Young (18–23 years), old (60–65 years), and older (70–75 years) adults were instructed to minimize body motion while seated on a wooden box with an AMTI force platform directly below. Four seated stationary postural trials of 20 s in length were conducted with force platform data sampled at 150 Hz. Significant Age × Frequency interactions were
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found for the ApEn of the COP on both axes of motion. Post hoc tests of the interactions revealed that aging significantly reduced the complexity of the postural dynamics, but only within the 0–4 Hz frequency band. These findings show that the loss of postural complexity with aging occurs predominantly within the centrally controllable higher brain structures that drive the lower (0–4 Hz) frequency and larger amplitude fluctuations in sitting postural dynamics. These findings point to the possibility for rehabilitative interventions to enhance complexity and reduce the amplitude of postural sway through selective focus on the key time scales of steady state dynamics. Discrete – rhythmic coordination as a window into generic coordination principles Jirsa, Viktor, CNRS and Université de la Méditerranée; Raoul Huys, Université de la Méditerranée; Sarah Calvin, CNRS and Université de la Méditerranée It is well known that two (almost) simultaneously executed discrete or rhythmic limb movements affect each another. While discrete movements and interferences between them are mainly investigated from a cognitive perspective, the interference of rhythmic movements is primarily studied from a dynamical framework perspective. While both communities have successfully developed tools and paradigms to study their domain-specific phenomena, the applicability of these to the other respective domain is limited. It therefore remains unclear whether the same principles underlie the motor behavior observed in both domains (as claimed in Kelso, 1995) or not (Schmidt & Lee, 2005). In order to address this issue, we examined the interference between simultaneously executed discrete and rhythmic wrist movements from the perspective of coordination dynamics. Rhythmic movements affected the discrete movements in a movement-frequency dependent manner: Reaction time and movement time decreased with increasing movement frequency. The discrete movements affected the rhythmic movements (by decelerating, accelerating, or leaving it unaffected) in a manner that depended on movement frequency and on the phase of the rhythmic movement at which the discrete movement was initiated. Specifically, the acceleration/deceleration profile revealed a bimodal structure as a function of phase for low frequencies, which gave way to a unimodal structure at high frequencies. This interference effect thus mimicked the hallmark feature of rhythmic-rhythmic coordination, and suggests that interferences between movements may be invariant across different movement types What do novices think about when learning a motor skill: An exploration of the explicit rule formation process Kadivar, Zahra; Jared M. Porter, Louisiana State University; Richard A. Magill, New York University Not much is known about the rules or strategies beginners use when initially learning motor skills. The purpose of this study was to evaluate the explicit rule formation process. Novice participants (N = 30) putted a golf ball toward a target located 3.05 m away for 50 trials. Radial error measures were taken after each putt. After every 10 trials participants were asked “What rules, knowledge, methods, or techniques did you use to help you putt the golf ball into the cup?” Verbal responses were recorded on an audio tape recorder and later transcribed verbatim. Statistical analysis revealed that only 4 participants showed significant improvements in performance. Because of high performance variability, we concluded participants remained in the initial stages of learning throughout the practice session. Transcribed verbal reports were categorized based on content. The most common
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rules reported were associated with regulation of force, 86%, and positioning of limbs, 73%, which were followed by rules involving the golf ball, 57%; the club, 50%; and the target, 43%. These results suggest that for this particular task novices develop rules based on internal aspects (e.g., force regulation and limb positioning) more than on the external factors (e.g., golf ball and club control). Further research is needed to understand if the rule formation process changes as learner’s progress through the stages of learning. Future work should also investigate how instructions and demonstrations provided by coaches, teachers, or therapists impact the explicit rule formation process. Role of motor memory consolidation as a potential mechanism for learning- performance distinction: A pilot investigation with repetitive transcranial magnetic stimulation Kantak, Shailesh S.; Katherine J. Sullivan, University of Southern California Motor learning studies demonstrate that the beneficial effects of certain practice conditions (e.g., variable practice) are evident during the delayed, but not immediate retention/transfer test. This phenomenon is known as the learning-performance distinction. The mechanisms that may be responsible for the difference between immediate and delayed retention/transfer are not known. The purpose of this study was to investigate the role of motor memory consolidation as a potential mechanism for the learning-performance distinction following acquisition under variable and constant task practice conditions. Twenty young adults (mean age: 26.2 years) practiced a discrete arm movement for 120 trials using a lightweight lever. Participants were randomized to 4 experimental groups: constant practice (CP), variable practice (VP), constant practice with rTMS postpractice (CP-rTMS) and variable practice with rTMS postpractice (VP-rTMS). The CP and CP-rTMS groups practiced a discrete ballistic arm movement task under single amplitude parameter condition, whereas the VP and VP-rTMS groups practiced the task under 4 different amplitude parameters. In the rTMS groups, we applied 1-Hz rTMS at 110% motor threshold intensity for 10 min over M1 postpractice to directly perturb motor memory consolidation. The effect of the rTMS perturbation on motor learning was determined during the delayed retention/transfer test. Motor skill was quantified by root mean square error (RMSE). Performance at the delayed retention/transfer tests indicated that variable practice was more beneficial to motor learning than constant practice. With a small sample size, the differences were not statistically significant (p = 0.9); however, the effect size was moderate (ES = 0.45). More importantly, rTMS applied post practice disrupted motor learning in the constant (RMSE: CP-rTMS > CP, ES = 1.3) but not variable practice (RMSE: VP-rTMS = VP, ES = 0.2) condition. This pattern of results suggests a differential role for M1 during motor memory consolidation under constant and variable practice conditions. Effect of optic flow produced by virtual reality on gait variability Katsavelis, Dimitrios; Leslie Decker, Naomi Kochi, University of Nebraska at Omaha; Nick Stergiou, University of Nebraska at Omaha and University of Nebraska Medical Center, Omaha Manipulation of the optic flow (OF) speed in virtual reality (VR) environments has been used for gait training in pathological populations to promote faster walking speeds. However, previous studies have only used mean values to examine gait without exploring changes in gait variability. Our goal was to investigate the effects of OF speeds on gait variability. Six healthy young adults walked on a treadmill for 15 min at their preferred walking speed
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(PWS) under 4 randomly presented conditions: (1) no OF (no-VR), (2) OF perceptually equivalent to the PWS (OFnorm), (3) fast OF velocity (OFfast: 150% of PWS), and (4) slow OF velocity (OFslow: 50% of PWS). The VR environment consisted of walking with stereoscopic glasses in a virtual corridor. Variability of lower-limb sagittal joints angles was analyzed with linear measures (SD: standard deviation, CV: coefficient of variation) and a nonlinear measure (ApEn: approximate entropy). Surrogate algorithms were also used to identify the presence of determinism in the data. Statistical analysis consisted of one-way repeated measures ANOVA. Our surrogation analysis revealed that the original data set is more than a linear stochastic system but rather has determinism and greater complexity. ApEn results revealed significant differences for maximum hip extension, flexion, and ROM, as well as for the ankle dorsiflexion position and knee ROM. The results also revealed that asynchrony between the OF speed produced by virtual reality and the subject’s walking speed increased kinematic variability of lower-limb joints angles as measured by ApEn, whereas linear measures yielded nonsignificant results. More importantly, ApEn findings revealed less predictable locomotive patterns with less regularity in the asynchrony conditions. Thus, optic flow in a VR environment can result in changes in the control mechanisms during walking as shown by gait variability. This research was funded by the Nebraska Research Initiative. Comparison of heart rate variability between rest and different task conditions for a repetitive throwing task Kee, Ying Hwa; Yeou-Teh Liu, National Taiwan Normal University This study examined whether heart rate variability during the performance of repetitive throwing tasks, with and without target, differ from being at rest. The underlying assumption is that the presence and absence of target affords distinctive task difficulty and could elicit different psychology. In this study, 18 healthy participants (5 women, 13 men; M = 26.4 years old, SD = 4.3 years old) underwent the following conditions while quietly seated on a chair: (1) baseline—5 min of spontaneous breathing without exaggerated movement, (2) no target—throwing 80 table tennis balls repetitively at a 5-s interval to an unmarked region approximately 2 m ahead, and (3) target—throwing 80 table tennis balls repetitively at a 5-s interval into a 26-cm × 26-cm target box placed 2 m ahead, where a token prize was rewarded to the highest scorer. Participants’ heart rate information was collected using Polar Heart Rate Monitor S810i (Polar Electro, Oy, Finland). Analysis of the next amplitude plot for the R-R interval time series (5 min per condition) was done using the HRV Analysis Software v1.1 (Biosignal Analysis Group, Finland). Results of the paired sample t test shows that the deterministic component (SD2) of the heart rate variability is significantly lower during No target (M = 44.4 ms) compared with baseline (M = 55.9 ms), t(17) = 2.88, p < .05, ES = 0.53. No significant difference is observed between target and baseline for this heart rate variability measure. Mean heart rates between baseline and both task conditions were also found to be similar. In summary, only the deterministic component of the heart rate variability during no target is significantly lower than baseline. Given the reduced heart rate variability observed in the no target, it is postulated that performing a repetitive task without an aiming component might have decreased autonomic modulation, and may be associated with the lack of psychological arousal during this nonevaluative phase. Further research on heart rate variability as an indirect measure of psychological change during motor tasks may be warranted.
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Influences of coordination dynamics and semantic retrieval parameters during dual task performance Kiefer, Adam W., University of Cincinnati; Bonny Christopher, San Jose State University; Kevin Shockley, University of Cincinnati Coordinating two limbs to produce rhythmic patterns is an elementary behavior and is commonplace in activities such as locomotion, typing, and musical performance. Recent studies have indicated that coordination of rhythmic movements, e.g., oscillating the hands in a synchronized pattern, is influenced by concurrent cognitive activity (Pellecchia et al., 2005; Shockley & Turvey, 2005, 2006). For instance, when Shockley and Turvey (2006) instructed individuals to perform an interlimb pendulum-oscillating task in conjunction with a semantic retrieval task for 30 s, cumulative recall decreased and the relative phase (i.e., attractor location of the coordinated limbs) increased. However, due to the short duration of the retrieval task, the mutual influence of coordination parameters and cognitive parameters other than cumulative recall, e.g., retrieval rate, could not be evaluated. The present experiment examined these mutual parametric influences using a coordination and semantic memory retrieval task over a longer 3-min period. In the present study, 16 participants performed two tasks separately and concurrently—an interlimb coordination task oscillating symmetric and asymmetric pendulums in an in-phase pattern, and a semantic retrieval task verbally generating members of a semantic category. There were no differences in retrieval errors or cumulative responses (p > .05); however, retrieval asymptote latency (i.e., retrieval rate) was significantly longer when concurrently performing the two tasks relative to the retrieval-only condition, F(2, 14) = 3.983, p < .05. Coordination was more stable for symmetric limbs than asymmetric limbs, F(1, 15) = 6.757, p < .05, irrespective of task. There was a Task × Symmetry interaction for relative phase, F(1, 15) = 5.081, p < .05. Relative phase deviated more from in phase for asymmetric limbs than symmetric, and this difference was exaggerated in dual-task conditions relative to coordination only. The results suggest that the cognitive parameter, retrieval rate, may be linked to attractor location in coordinated limbs. Does your eye keep on the ball?: The strategy of eye movement for volleyball defensive player while spike serve reception Kim, Seonjin; Seung-Min Lee, Seoul National University The current investigation examined the different eye movements used by defenders during spike serve reception in a volleyball game. Six expert and six novice players participated in the experiment. The server exhibited randomized sever techniques (spike and ordinary server technique) to defenders. The study required having seven perfect serves received by a defender for data collection from mobile eye trackers to be able to measure/analyze defender’s eye movements. We analyzed defender eye movements during the following time period: The time started when a server tossed a ball in the air in preparation to serve to a defender and stopped when the defender made contact with the ball. The time phase classified into two categories: ball toss phase and flight phase. The results indicated that expert players were more focused on the server’s shoulder and arm region than novice players during the ball toss phase and experts were faster at tracking a ball than novice players during the flight phase.
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Detrended fluctuation analysis and entropy rate reveal motor control strategies in the variability of step activity data Kochi, Naomi; Nicholas Stergiou, University of Nebraska at Omaha; Jim Cavanaugh, University of New England The StepWatch3 (SW3) activity monitor is an instrument that records step counts at frequent intervals from individuals ambulating in their customary living environment. Traditionally the SW3 has been used to measure the volume of activity (i.e., total steps or minutes) accumulated during a given recording period. In this study, we explored whether SW3 data also could be analyzed to illuminate the underlying control of ambulatory activity. We used detrended fluctuation analysis (DFA) and entropy rate (ER) to examine the minute-to-minute variability of step count values collected from 157 subjects over 14 days. Detrended fluctuation analysis examined the presence of memory in the data by estimating long-range correlation exponents (alpha); ER examined temporal structure in the data by quantifying the amount of uncertainty generated by the underlying control system. Subjects were separated into three groups based on the average number of steps per day: 46 highly active subjects (more than 10,000 steps); 86 moderately active subjects (between 5,000 and 10,000 steps); and 25 inactive subjects (less than 5,000 steps). Our results revealed that the DFA and ER differentiated the three groups. Detrended fluctuation analysis revealed a greater presence of long-term memory in the data of highly active subjects and a smaller presence of long-term memory in the data of inactive subjects. However, significant correlations between the number of steps and alpha values were found in each group. Entropy rate revealed significant differences in temporal structure among the groups. Furthermore, greater entropy rates for highly active subjects suggest that their data had more complex structure. These results support our hypothesis that, in addition to the volume of activity produced by an individual, patterns of ambulatory activity may reveal important characteristics of the underlying control system responsible for their production. This work was supported by the NIH (K25HD047194), NIA (1 R21 AG027072-01), the Department of Veterans Affairs, and the Nebraska Research Initiative. Perceptual influences on Fitts’s law: Asymmetries associated with limb dominance Kovacs, Attila J.; John J. Buchanan, Texas A&M University; Dongwook Han, Seoul National University; Charles H. Shea, Texas A&M University The linear relationship between movement time (MT) and index of difficulty (ID) for Fitts type tasks has proven ubiquitous over a variety of experimental settings. Much of the support for this linear MT/ID relationship has been provided from tasks emphasizing the motor half of the action-perception cycle. In the current experiment, we examine the contribution of the perceptual half of the action-perception cycle to the generation of the MT/ID relationship. The present experiment compared dominant right-arm and nondominant left-arm rapid aiming performance using normal and enhanced visual displays. The manipulation visually scaled target amplitude (A) and target width (W) in a proportional manner in order to generate perceptually larger displays for fixed IDs. Three IDs (3.0, 4.5, and 6.0) with three display conditions were utilized. Participants had to move a dot between two targets projected on the wall by moving a horizontal lever without vision of the arm. For both dominant and nondominant limbs, the results demonstrate that given more salient visual feedback participants can decrease MT in high-ID (ID = 6) conditions more so than in low-ID (ID = 4.5 and 3) conditions, resulting in a nonlinear MT/ID relationship. With ID = 6, the enhanced visual display afforded the production of a smoother and more harmonic aiming motion.
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The enhanced visual display did not alter the smoothness or harmonic nature of the aiming motion with ID = 3 or 4.5. The changes in movement production (smoothness, harmonicity) were linked to a greater proportion of total MT being devoted to the movement’s deceleration phase. The data provide evidence that enhanced visual displays have a larger impact on difficult movements (ID = 6) assembled from discrete motor primitives compared to easier movements (ID = 3) assembled from cyclical motor primitives; in turn, altering the ubiquitous linear relationship between MT and ID. In addition, limb asymmetries were noted, suggesting an increased reliance on cyclical motor primitives for the nondominant left-arm compared to the dominant right-arm. The coding of rapid movement sequences Kovacs, Attila J., Texas A&M University; Dongwook Han, Seoul National University; Charles H. Shea, Texas A&M University A number of theoretical perspectives (e.g., Hikosaka et al., 1999) argue that during the learning of sequential movements different coordinate systems are utilized early (e.g., visual-spatial) and late (e.g., motor) in practice. Additionally, recent results suggest (Kovacs, Muehlbauer, & Shea, 2008) that intermanual transfer is symmetric for visual-spatial coordinates whereas motor coordinates transfer is asymmetric. However, this research has utilized relatively complex movement sequences that may be more dependent on visual-spatial information than less complex movement sequences. In the present experiment, rapid sequential movements were utilized where participants had to make a pattern of elbow flexions-extensions in an attempt to match a goal pattern. One task consisted of 4 elements (easy task) and the other task consisted of 6 elements (difficult task). Participants were assigned to either the “easy” or “difficult” task with 11 blocks of practice. Coding of the movement sequence was assessed using a retention test and three transfer tests where the visual-spatial, motor, or neither code was reinstated on the transfer test. We hypothesized that the motor representation would develop earlier for the easy task compared to the difficult task, thus yielding better performance on the corresponding transfer test. Conversely, for the difficult task performance may be better when visual-spatial coordinates were reinstated on the transfer test. Consistent with our prediction, performance on the motor transfer test was as good as the retention when a relatively easy flexion-extension pattern was used. However, for a relatively more difficult task, performance on the visual transfer task was as good as the retention and performance on the motor transfer test showed decreased performance. Our results indicate that the degree to which a representation in motor coordinates develops is directly related to the difficulty of the task performed. Interestingly, we also found some coding asymmetries related to the order in which the hands were used during acquisition. The influence of surface pattern on the timing of muscle preactivation in landings Kreider, Charlene R., Daniel M. Russell, Bruce D. Hale, Pennsylvania State University Berks; Ben Sidaway, Husson College In order to land safely from a fall, muscles are activated prior to contact with the ground. Preactivation of the rectus femoris has been found to coincide with a τ-margin, rather than a consistent time-to-contact, for falls from differing heights (Sidaway et al., 1989). This finding suggests that the optic variable τ is employed for timing actions (Lee, 1980), even when it underestimates time-to-contact due to an accelerative approach. Obtaining timing information from the rate of retinal expansion may be influenced by the pattern on the approaching
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surface. Specifically, a checkered surface may provide more precise timing information than a solid surface. This research compared the timing of muscle preactivation for landing on checkered and solid surfaces. Nine participants performed landings on two different visual surfaces, from 3 different heights: 0.4, 0.8, and 1.2 m. Five trials were performed for each condition by all participants. The visual surfaces were solid blue, and a blue and white check pattern. Electromyography was employed to measure rectus femoris activity, and the impact with the ground was determined from an accelerometer placed above the ankle. Using equations of motion, τ and time-to-contact were computed at the initiation of muscle activity. In agreement with Sidaway et al. (1989), time-to-contact was significantly different across drop heights, but τ-margin was not. This supports the view that the optic variable τ is used in judging landings over directly computing time to contact. Surface pattern had no significant effect on the timing of muscle preactivation. Recommendations are made for further examination of the possible role of surface pattern in the timing of landings. Effects of bilateral practice on coding and transfer of simple movement sequences Krüger, Melanie, University of Leipzig; Attila J. Kovacs, Texas A&M University; Thomas Mühlbauer, University of Basel; Stefan Panzer, University of Leipzig; Charles H. Shea, Texas A&M University Previous research (e.g., Hikosaka et al., 1999; Bapi, Doya, & Harner, 2000) suggests that movements are represented early in practice in visual-spatial coordinates/codes, which are effector independent, and later in practice in motor coordinates/codes, which are effector dependent. However, recent research (Kovacs, Muehlbauer, & Shea, 2008) using complex 14-element movement sequences indicated strong reliance on visual spatial codes even after 12 days of practice. In the present experiment, the task was to reproduce a less complex 1.5-s pattern of elbow flexions and extensions. A bilateral practice/transfer paradigm was used, where participants initially practiced the task with one limb and then with the contralateral limb. On the contralateral limb either the visual-spatial, motor, or neither coordinates were reinstated. In order to assess interference/consolidation effects, if any, the practice sessions were separated by a few minutes or 24 hours. In contrast to our previous experiments, the results indicated a strong advantage for the participants who practiced the same motor code over the two sessions compared to the subjects who practiced the same visual-spatial code or where the codes were changed across sessions (neither condition). Further the results were similar for participants starting with the left and right limbs. These findings are interesting because they indicate that the motor code can be developed early in practice through bilateral practice provided the same motor coordinates are used and bilateral motor coordinate practice can lead to effector independent motor codes. Further, these results are opposite of recent results by Panzer et al. (2008) using a more complex movement sequence where maintaining visual-spatial codes across bilateral practice resulted in enhance retention and transfer, suggesting that different tasks (e.g., simple vs. complex) may benefit from different practice schemes. The spatiotemporal entropy analysis of discrete aiming movements Lai, Shih-Chiung; National Taipei College of Nursing; Karl M. Newell, Pennsylvania State University The spatial and temporal movement variability are usually measured and compared in their own domains. This study, based on the information entropy idea, applied the probabilistic
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approach to reveal the unified spatiotemporal nature of movement variability. The effects of instructional strategy space-emphasis and time-emphasis and task demand point-aiming and target-aiming were investigated on the discrete aiming movements. Twelve young adults were randomly assigned to one of two movement strategy groups. Both groups performed the point-aiming and target-aiming tasks. The primary data analysis focused on the probabilistic evaluations, i.e., the unified spatiotemporal entropy. It was found, in the target-aiming tasks, that the space-emphasis group generated relatively lower space-time combined entropy than the time-emphasis group. The combined entropy, for the time-emphasis group, was significantly higher for the target-timing than the point-timing tasks. These results supported the advantages of using the probabilistic analyses in the movement speed-accuracy paradigm. Navigation errors and reaction times during blind navigation towards a previously seen target Lajoie, Yves; Nicole Paquet, Renée Lafleur, University of Ottawa Introduction: The cognitive processes that underlie reaching a previously seen target while walking without vision are mainly unknown. Reaction times were gathered to estimate the attentional resource required to perform this task. The aims of this dual-task study were (1) to determine the effect of responding verbally to an auditory cue reaction time on distance and direction errors during blind navigation, and (2) to determine whether reaction times changed as subjects navigated towards the target. Methods: Seven healthy subjects (24.9 ± 2.3 years old) walked without vision towards a target located on the floor 8 m ahead. They walked until they believed their feet were on the target. Distance traveled (DT), angular deviation (AD), and body rotation (BR) relative to space were measured. Reaction times (RT) were obtained from subjects responding verbally, “top,” as quickly as possible after an auditory cue, which was delivered during one of the four 2-m distance intervals along the 8-m blind navigation path. RTs were also recorded during sitting without vision. Results: On average, subjects did not walk far enough and undershot the target during navigation (DT = 754 ± 89 cm) and during the dual task (DT = 789 ± 85 cm). The production of a verbal response did not change AD and BR, but DT was longer p < 0.01 during the dual task than during navigation only. RTs were longer (p < 0.01) during navigation than during the control sitting condition. During navigation, RTs were longer (p < 0.01) in the last 2-m distance interval, when subjects got close to the target. Discussion: Our preliminary results indicate that navigation without vision required significantly more attentional resources than sitting, as shown by longer RTs. Furthermore, the attention needed to perform navigation increased as subjects approached the target, which suggests that subjects wondered if they had arrived or not. The additional cognitive load caused by the production of a verbal response did not result in larger directional errors but had a significant impact on the distance traveled. A novel training program for learning robot-assisted surgery Lee, Irene H.; University of Nebraska Medical Center; Ka-Chun Siu, Mukul Mukherjee, University of Nebraska at Omaha; Dmitry Oleynikov, University of Nebraska Medical Center; Nick Stergiou, University of Nebraska at Omaha Although the use of robot-assisted surgery has increased in popularity, the development of training protocols is limited. Establishing a training program with different levels of task complexity is important for new surgeons to learn how to perform complex surgical skills. The purpose of this study was to evaluate a training program that we have developed
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based on previous research that includes a variety of surgical tasks that range from basic to advanced. Medical students without surgical experience participated in our 5-day training program using the da Vinci Robotic Surgical System (Intuitive Surgical Inc., Sunnyvale, CA, USA). Measures included time to task completion, and speed and distance traveled by the instrument tips. Electromyography of the wrist flexor and extensor were also analyzed. Performance was also graded by an experienced surgeon using the modified objective structured assessment of technical skills for robotic surgery. Lastly, participants self-evaluated their performance with a set of questionnaires. Preliminary results show that the time to task completion was decreased and that the distance and speed were increased. Subjective assessments improved after training. Participants reported better mastery, familiarity, and selfconfidence and less difficulty in performing tasks after both posttesting and on the retention sessions. Our training program successfully assisted participants in learning to operate the surgical robot with surgical tasks of differing complexities. All participants improved their basic robotic surgical skills after the 5-day training program. Their performance became more consistent and required less muscle activity. Learning complex surgical skills may require a program with a variety of task difficulties. Further studies are required to verify these findings with more participants. This work was supported by the Nebraska Research Initiative, NIH (K25HD047194), and NIDRR (H133G040118). Adaptive angle between rider and bicycle symmetry axes as emergent property of stabilization on a circular track at variable speeds? Lee, I Chieh; Graduate Institute of Exercise and Sport Science It is more difficult to make a turn on a bicycle than to ride straight ahead. It is a fact, however, that we usually acquire the turning skill without any explicit instructions about how to make the turn. In dynamical systems theory, the emergence of a new coordination pattern often comes from the self-organization of the subsystems (Schoener & Kelso, 1988). In bicycle riding, in addition to controlling the bicycle handles in order to stay on the track, the center of mass of the bicycle-rider system needs to tilt in the turning direction in order to compensate for centrifugal forces and make a successful turn. These forces increase with angular velocity and a counterforce needs to increase as well by decreasing the inclination angle of the bicycle-rider system in order to maintain balance. We observed 6 participants riding a bicycle along a 5-m-diameter circle track from slow to fast speed; the experiments were captured with two cameras (30 Hz), and the relationship between the rider and the bicycle was analyzed with a 3-D motion digitizing system. The results showed that the symmetry line of the rider was leaning more toward the center of circle than the symmetry line of the bicycle during the slow speed, but the angle between the bicycle and the ground decreased with increasing speed, t(5) = −7.753, p < .05. When the speed increased, the symmetry line of the rider leaned further away from the center, t(5) = −7.88, p < .05, and the angle between the symmetry lines of the rider and the bicycle increased, t(5) = −5.025, p < .05. The results of the study are discussed based on the tri-angular constraint model of Newell (1985), and the comparison of the bicycle speed and angle of the rider-bicycle system during racing conditions are also discussed. Coordination of head and putter movement in expert and less-skilled golfers Lee, Timothy D.; McMaster University; Tadao Ishikura, Doshisha University; Stefan Kegel, Dave Gonzalez, Steven Passmore, McMaster University
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Coordination of two or more degrees of freedom is a requirement for most voluntary physical activities. Sometimes a particular coordination pattern is consistent with skilled performance. At other times the pattern represents poor technique, perhaps even a barrier to skill proficiency. Putting, in golf, is one example. In putting, most instructors consider the in-phase coordination of the golfer’s head and the motions of the putter to be representative of poor technique. Instead, instructors recommend that the head be kept as motionless as possible while the putting stroke is executed. Our goal was to assess if this was so, and under what conditions. We examined the coordination putting patterns of 11 less-skilled (M handicap = 23) and 5 expert golfers (three professionals, two expert amateurs). All golfers performed 10 putts on an indoor-putting surface to one of three circular targets 1, 3, and 5 m away in trials with a ball present and putted or not present (a practice stroke). Measures included final ball position error scores and kinematic analyses of the putter-head and the golfer’s head using an Optotrack system. As expected, the expert golfers performed better than the less-skilled golfers on a large number of outcome and kinematic measures, especially so for measures of repeatability. However, the most dramatic finding was that displacements of the head and putter revealed high positive correlations for the less-skilled golfers, M = 0.63, indicating strong in-phase coordination, but that the experts revealed a high negative correlation M = −0.77, indicating a strong antiphase coordination. Velocity correlations were even higher r’s of 0.91 vs. −0.87 for less-skilled and expert golfers. Skill level did not interact with distance of the intended putt or the presence/absence of a ball. These findings offer preliminary evidence that there are clear differences in putting coordination modes between expert and less-skilled golfers. Further work is underway to determine if this knowledge can be used to accelerate the acquisition of putting skill. Spatial and temporal accuracy do not emerge simultaneously during the learning of a one-handed catch Lenoir, Matthieu; Pieter T. Tijtgat, Dirk L. De Clercq, Simon J. Bennett, Ghent University; Geert J. Savelsbergh, Manchester Metropolitan University and VU Amsterdam Spatial and temporal accuracy do not emerge simultaneously during the learning of a one-handed catch. According to Marteniuk and Romanov (1983), learners first acquire the spatial characteristics of a new motor skill before they learn to cope with temporal aspects, although some overlap is undeniable. Mazyn et al. (2007) found some support for this notion, although this was limited given the rather constrained ball trajectory of the practice conditions (i.e., low temporal and spatial variability). It was our objective in this study to better determine how novice catchers deal with spatial and temporal constraints of one-handed catching during learning. To this end, conditions involving three ball speeds (10, 12,14 m/s) and four arrival locations with respect to the shoulder of the catching arm (upper left, lower left, upper right, lower right) were randomly provided to ten female poor catchers. After a two-week training program of 1,080 trials, catching performance with the nondominant hand increased more (from 26% to 53%) than a control group (25% to 32%; p < .005). The learning curve (number of successful catches) was characterized by a sharp increase on the first two days, followed by a plateau that lasted for three days, and finally a second increase during the last three sessions. More than half (53%) of the total decrease in spatial errors over the whole acquisition period occurred in the first half of learning, whereas temporal errors diminished mainly in the second half of the experiment (only 19% of the total decrease occurred in the first half). These results support the idea that spatial changes partially precede temporal adaptations in movement execution. Further investigation of the
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kinematics of the catch will seek to reveal the mechanisms underlying these spatial and temporal changes at the performance level. Just noticeable difference thresholds of passive limb motion in healthy adults Li, Kuan-Yi, Kristen A. Pickett, Jürgen Konczak; University of Minnesota The aim of this study was to gain normative data from healthy subjects on their ability to discriminate between two passive limb motions. Knowledge about such just noticeable difference (JND) thresholds for passive limb motion sense can be used to assess the degree of perceptual dysfunction in patients with peripheral and central nervous system disease. Without vision, right-hand dominant healthy adults (N = 30) rested their arms on the padded, metal testing apparatus (9 cm × 60 cm). The subject’s forearm was passively moved by a torque motor connected to the passive motion apparatus causing either elbow flexion or extension of the elbow. The starting position of the splint corresponded to a 90° elbow angle. Each trial presented a pair of angular velocities separated by a 3-s interstimulus interval and consisted of one standard velocity (1.15 deg/s: fast condition; 0.60 deg/s: slow condition) and one comparison velocity. At the end of the trial, subjects indicated if the two stimuli were the “same” or “different.” Two fixed staircase procedures with a step size of 0.1 deg/s were employed. The range of comparison velocities was 0.1–1.1 or 0.65–1.65 deg/s depending the condition. ∆stim is defined as the difference between the standard and comparison velocity for each trial. The JND threshold was determined to be the ∆stim value at which a probability of 75% correct response was achieved. We found that the ability to discriminate between two angular velocities increased almost linearly in the slow condition, where the thresholds were 0.39 deg/s for flexion and 0.38 deg/s for extension. In the fast condition, 60% of our subjects reached 75% correct response at a ∆stim of 0.4–0.5 deg/s; however, the mean of all subjects did not reach 75% correct response in the range of ∆stim. The direction of arm movement had no effect on passive motion discrimination thresholds. The sensitivity to discriminate between angular velocities was velocity dependent. For standard velocities below 1 deg/s, the acuity to discriminate to limb velocities was approximately 0.4 deg/s. Dominant vs. nondominant differences in learning a tracing task with weighted feedback function Liu, Yeou-The; Ya-Ting Yen; National Taiwan Normal University; Gottfried J. Mayer, Karl M. Newell; Pennsylvania State University Most measurements in motor skill learning experiments are based on single variable data, but this is difficult to justify in a multi-segment coordination task. There have been limited methods for quantifying multi-segment coordination learning in the literature such as principle component analysis and Cauchy criterion, but these methods cannot be completely useful without also measuring another variable (the outcome or score of the task). The current research used a weighted feedback function to guide the practice performance and to examine the kinematic characteristics of the limb movements of 12 participants performing a mirror tracing task. In addition to 5 days of practicing the mirror tracing task with the dominant hand, we also examined groups who did normal image tracing with the dominant or nondominant hand. The results showed that most of the participants adopted the “speed” strategy during later practice sessions of the mirror tracing task and the dominant hand normal tracing task, but the “accuracy” strategy was observed more frequently during the early practice of the mirror tracing task and the nondominant hand normal tracing task.
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The controllability was measured by the variability of the detrended performance scores and showed a superior level for the 2 normal image tracing conditions over the mirror tracing conditions. From the range of motions of the 3 joints of the arm, it was also found that participants tended to freeze the distant joint of the limb when performing tasks with the nondominant hand compared to the mirror tracing tasks with the dominant hand. The mirror image tracing task provided a perceptual-motor coordination problem that placed an additional demand on the motor coordination. It is the coupling between perception and motor systems that was being learned over the practice sessions. Asymmetry in emotion and motor systems Lodha, Neha; Stephen A. Coombes, Sagar K. Naik, Christopher M. Janelle, James H. Cauraugh, University of Florida Substantial empirical work suggests that emotional stimuli are processed asymmetrically in the human cortex (left hemisphere = pleasant; right hemisphere = unpleasant). Two studies were designed to determine whether asymmetry in the emotion and motor systems interact. In Study 1, subjects (N = 22) pinched a force transducer using either the right (RH) or left (LH) hand to match a target force set at 10% of maximum voluntary contraction. Each 20-s trial began with 8 s of visual feedback. During 20 trials, feedback was replaced with a mutilation, erotica, neutral, or blank image. During 5 control trials feedback remained visible for the full 20 s. Accuracy (least error for control < erotica = mutilation < neutral; RH = LH), variability (control < all; RH < LH), and complexity scores (control > all; RH = LH) replicated previous evidence and supported an emotional arousal interpretation. To control for the possibility that the pinch grip bilaterally activated the motor cortex, potentially masking the impact of emotional asymmetry on motor output, we modified the task in Study 2. Subjects (N = 23) produced force by extending the wrist and fingers of their right and left limbs. We hypothesized that the recruitment of larger muscle groups would lead to more distinct contralateral activation of motor regions, thereby isolating and integrating specific emotion and motor processes. All other factors were held constant. Greater error was evidenced by the LH during exposure to erotica images and greater error was evidenced by the RH during exposure to mutilation images, demonstrating that distinct emotional processes differentially impact the motor system in an asymmetrical fashion. Variability and complexity scores replicated findings in Study 1. Collectively these findings show that although affective processes remain asymmetrical, the impact of emotional valence on motor function is determined by task dependent recruitment of bilateral or unilateral motor regions. The effects of attentional focus on the neurophysiological correlates of finger movements Lorey, Britta; Karen Zentgraf, Cris Zimmermann, Rudolf Stark, Matthias Bischoff, Jörn Munzert, Justus-Liebig University Giessen Previous studies have shown that adopting an external focus of attention enhances motor learning and performance (see, for a review, Wulf, 2007). Moreover, by using neuroimaging methods, it has been possible to demonstrate that attention actually modulates the neuronal network for motor control (Binkofski et al., 2002; Johansen-Berg et al., 2002; Rowe et al., 2002). The present study used functional magnetic resonance tomography to determine the effects of an instructed attentional focus while performing a finger-tapping sequence. In a between-subject design, 32 healthy, right-handed volunteers learned the sequence either with
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an internal or an external focus. Participants were then scanned during their performance of finger tapping in the respective focus condition—“internal” with their attention directed to their fingers or “external” with their attention directed to the buttons. Contrasted to rest, a between-subject second-level analysis showed that attentional focus activated left primary motor as well as primary somatosensory cortex differentially. This study leads to the conclusion that the sensorimotor system represents different attentional states in performing a behaviorally identical finger-tapping task. Studying the neuronal correlates of attentional foci in motor control and learning might in the long run offer a neurophysiological explanation of the differential effects found in behavioral studies. The influence of judgment fallacies and prior viewing experience on ball-strike decisions MacMahon, Clare; Victoria University Two studies explored sequential decisions in sport. In Study 1, 50 participants with baseball experience (players and umpires) and 61 control participants with no baseball experience were presented with sequences of five ampersand symbols (&) and six pound symbols (#). The rate of alternation between these two symbols was varied between 0.2 and 0.8 such that some sequences represented “streaks” of one or the other symbol. Participants were asked to decide whether each sequence represented the outcome of a coin toss (heads and tails) or a series of pitches (ball and strike). A 2 Group (experience, control) × 7 Alternation Rate (0.2., 0.3., 0.4, 0.5, 0.6, 0.7, 0.8) ANOVA with repeated measures revealed a main effect of alternation rate, F(6, 104) = 7.36, p < .01, and an interaction between alternation rate and group, F(6, 104) = 2.62, p < .05. Post hoc tests showed a significant difference at the 0.5 alternation rate (p < .01) and borderline differences at 0.2 and 0.7. In line with previous findings (Ayton & Fischer, 2004), controls attributed low-alternation rates or “streaks” to baseball pitches and high alternation rates to coin tosses. Experienced participants did not fall into this pattern. Study 2 tested 50 umpires and players and 52 control participants’ ball-strike decisions for ambiguous pitches. Group 1 viewed no warm-up, while two other groups viewed a poorly performing pitcher (2 strikes, 8 balls). Group 2 was told the warmup pitcher was a teammate of the target pitcher, and Group 3 was told he was an opponent. Experienced participants rated test pitches more strike-like overall, F(1, 96) = 12.50, p < .01, and groups who had seen a poor pitcher at warm-up rated test pitches more ball-like, F(2, 96) = 6.67, p < .01, regardless of whether they believed it was a teammate or opponent. When the sequence of pitches were analyzed by serial position, both of these effects dissipated after the first 9 or 18 pitches. These findings provide insight into the application of decision models, such as Mussweiler’s (2003) selective accessibility model. Interception enhances anticipation of advance kinematic information Mann, David L.; University of New South Wales and Australian Institute of Sport; Bruce A. Abernethy, University of Hong Kong; Damian T. Farrow, Australian Institute of Sport The ability to anticipate the actions of an opponent is a well-established characteristic of expertise in many interceptive sports, yet the verbal responses typically relied upon when examining this skill fall short of accurately representing the constraints under which the athlete performs. Although expert anticipation is enhanced when a simple movement is coupled to the perception of live advance information (Farrow & Abernethy, 2003), recent
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neuropsychological evidence suggests that an attempt at intercepting the oncoming object may be required to accurately test the perceptual-motor pathway utilized in a performance environment. The present study examined the relationship between perception-action (PA) coupling and anticipatory skill to determine whether a response requiring interception produced enhanced anticipation over and above that elicited by a simplified movement-based response. Twelve skilled and 11 novice cricket batsmen were required to predict the direction of balls bowled by intermediate players under four counterbalanced response conditions of increasing PA coupling: minimal (verbal), mild (lower-body movement only), moderate (full body movement with no bat), and high (full movement with bat to intercept ball). Plato liquid crystal goggles occluded the batsmen’s vision of the approaching bowler and ball at three different times relative to ball release (0 ms, +50 ms, no occlusion). An interaction was evident between skill level and coupling, F(3, 63) = 4.697, p < 0.01, in those trials occluded at ball release. Although novice participants demonstrated no change in performance across the four response types, there was a direct positive relationship between PA coupling and anticipation in the skilled group. Most importantly, performance in the highly coupled condition was significantly greater than in the moderate condition, which possessed an identical movement but without a bat to intercept the ball. These results will be considered in the context of the dual-pathway theory of vision (Milner & Goodale, 1995) along with implications for future testing. The role of vision during bilateral perturbation tasks Mason, Andrea H., University of Wisconsin–Madison The purpose of the present study was to investigate coordination of the two hands when one or both targets were displaced in a bimanual prehension task. Eleven right-handed volunteers were asked to reach 15 cm to grasp and lift two illuminated cubic objects (2-cm sides) with the right and left hands. Upon initiation of the reach, a perturbation could occur by extinguishing one or both objects and illuminating new objects located 30 cm away from the start position and directly in front of the initial objects. Subjects performed the following four conditions, which were presented in a randomized order: (1) 55 trials with no perturbation of either object (NN), (2) 15 trials with perturbation of the right object (NJ), (3) 15 trials with perturbation of the left object (JN), and (4) 15 trials with perturbation of both objects (JJ). Kinematic data for the initial reach to grasp was obtained for the index fingers, thumbs, and wrists of both hands using a VisualEyez (Phoenix Technologies) 3-D motion capture system. Results indicated that movement time was fastest for the unperturbed condition (900 ms), significantly slower for conditions where one object was perturbed (JN = 1,010 ms, NJ = 1,040 ms) and slowest when both objects were perturbed (JJ = 1,150 ms). For the JN and NJ conditions, the hand moving to the close target increased movement time compared to the NN condition, and the hand moving to the far target decreased movement time compared to the JJ condition such that movement times were similar for the two hands despite different travel distances. In contrast to the temporal coupling observed for movement time, the timing of peak velocity (TPV) and peak aperture (TPA) was scaled to movement distance for all conditions. Thus, for the JN and NJ conditions, TPV and TPA occurred later for the hand moving to the perturbed target compared to the unperturbed target. These results indicate the existence of independent motor plans for the two hands when performing bimanual tasks; however, when one object is perturbed, interference occurs at the motor execution level.
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Comparing motor speed and asymmetries in Parkinson’s disease and healthy control populations: Preliminary results Mayer, Matthew T., Mike Sage, Pam Bryden, Wilfrid Laurier University; Eric Roy, University of Waterloo; Quincy Almeida, Wilfrid Laurier University Parkinson’s disease (PD) is the most common movement disorder caused initially by unilateral degeneration of dopamine-producing neurons in the basal ganglia. Since one limb is typically more affected than the other, it is important to precisely measure the asymmetries in hand performance in order to accurately measure the effectiveness of treatment. The aim of the current study was to assess motor speed and asymmetries in individuals with PD in contrast to age-matched healthy controls using the grooved pegboard test (GPB). A total of 113 patients with PD underwent a clinical assessment of motor symptoms using the Unified Parkinson’s Disease Rating Scale (UPDRS). Participants also performed 2 trials of the GPB with both hands. A convenience sample of age-matched healthy adults also performed two trials of the GPB with both hands. The GPB was performed in two steps: the place phase, which required placement of 25 shaped pegs into oriented slots, and the remove phase, which required the removal of 25 slotted pegs into a receptacle. If participants could not complete the GPB task on the first try within 5 min, a count of inserted pegs was taken to calculate an insertion rate. The results reveal that PD patients took more time to perform both phases of the GPB. Despite the relative slowness of the patients, both groups demonstrated a preferred hand advantage that was significantly larger in the place than the remove phase. While the UPDRS is the gold standard for symptom assessment in PD, it is a subjective judgment at best. Therefore quantitative, objective measures are needed that measure functional capabilities of PD patients. Results will be discussed in terms of creating an objective measurement of functional capabilities in PD. Funding provided by NSERC (Bryden, Roy, and Almeida). Effects of increasing load on movement variability in the drop snatch squat exercise Meyer, Ben; John B. Shea, Indiana University Schmidt’s impulse-variability model hypothesizes that the initial phase of a movement, involving the generation of a force impulse, is more important than later phases of the movement dealing with ongoing control. Schmidt (1979) showed that the size of the subject’s error increased in proportion to the magnitude of the force used. This increased variability resulted in decreased movement accuracy. However, in the drop snatch squat exercise, it may be possible to have little to no change in movement accuracy (as defined by the barbell position at the lowest point of the motion) as the load is increased. In order to successfully complete a drop snatch squat exercise, athletes must move their body quickly in order to get under the barbell at the appropriate time. This high velocity motion requires the performer to exert large forces. However, athletes must also position themselves very accurately in order to safely catch the weight without losing their balance. The work presented here examines how alterations in load and amount of practice affect drop snatch squat performance. Participants in the study performed drop snatch squat exercises using a barbell loaded with plates (low, medium, and high load conditions). Half of the subjects were tested using ascending barbell loads and the remaining half of the subjects were tested using descending barbell loads. The positions of the barbell and selected body landmarks were analyzed at key points in the motion (baseline, high point, and low point). Comparisons were then made between the ascending and descending load conditions and between loads. Special attention was given to
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the baseline-to-high point distance, to the baseline-to-low point distance, and to the distance between high and low points. Results showed that with increasing load subjects increased their barbell high point, and that subjects were able to maintain a relatively stable barbell low point regardless of load. Subjects were therefore able to make adjustments to variations in load that did not increase movement variability. The information for interception: An in-situ examination of the timing of the visual information pick-up by cricket batsmen of different skill levels Muller, Sean; RMIT University; Bruce Abernethy, University of Hong Kong and University of Queensland; Damian Farrow, Australian Institute of Sport; Matthew Rose, Timothy Anderson, Michael Eid, Rohan McBean, Mike Rennie, David Ridley, and Phillip Buultjens; RMIT University The purpose of this study was to examine the respective contributions of advance, ball flight, and ball bounce information to expert interception in the skill of cricket batting using an experimental task that preserved as many of the natural constraints as possible. Six highly skilled and six low-skilled batsmen attempted to hit balls delivered by fast bowlers under conditions in which vision of the bowler’s prerelease movement patterns and the subsequent ball flight were selectively and unpredictably occluded using liquid crystal spectacles. Vision was occluded either just prior to ball release, just prior to ball bounce, or not at all, creating conditions in which only advance information arising from the bowler’s movement pattern was progressively supplemented by the availability of early pre-bounce and late post-bounce ball flight information. The bowlers delivered balls of two different types either swinging away or into the batsman and two different lengths either bouncing close to or well short of the batsman and the interest was in determining the accuracy of both the whole-body positioning movements and the finer bat-positioning movements of the batsmen. The former was measured by the appropriateness of the definitive foot movements made by the batsmen forward for balls bouncing close and back for balls bouncing short and the latter by quality of bat-ball contacts (cf. Müller & Abernethy, in press). The highly skilled players were superior to the less-skilled players in the number of correct definitive foot movements made across all conditions when the ball was of full length and in the release condition when the ball was delivered at a short length. In relation to bat-ball contact, the more skilled players were able to utilize information both prior to and after ball bounce to attain a greater number of “good” contacts. The in-situ occluding method reveals aspects of expertise not apparent within traditional laboratory measures of anticipation and may, consequently, also have utility for the training of interceptive skill. Perceptual judgments by either an actor or an observer are more accurate than the movement itself Munzert, Joern; Tanja Hohmann, Justus-Liebig University Giessen Based on the concept of internal models, motor representations can be postulated to not only guide movements but also be used for movement observation and the prediction of movement consequences. This is supported by fMRI data indicating neural activation in motor-relevant cortical and subcortical brain areas during action observation (cf. Zentgraf et al., 2005). The present study analyzed how accurately actors and observers can predict the outcome of boule shots when the ball flight is not visible. Actors had to hit goals at a distance of either 7 m, 7.5 m, or 8 m. Pairs of participants were formed in which one person
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was a blindfolded actor and the other an observer who could see only the movements of the actor, but not the ball flight itself. After each shot, both actor and observer had to estimate the actual distance of the shot. Both participants received feedback after judging shot length. Results showed that the absolute error (AE) for throwing accuracy was M = 0.53 m (SD = 0.19). The AE for the discrepancy between actual and predicted shot length for actors was M = 0.38 m (SD = 0.09), and that for observers, M = 0.40 m (SD = 0.12). Within-subject comparisons of actual and predicted shot length revealed significantly better judgments than throwing performance for actors, p < .001, η2 = .55. No significant effects were found for judgments of actors relying on their own actions compared with judgments of the observers, p > .45. The results show that predictions based on kinesthetic feedback (actors) and on visual feedback (observers) do not differ and that both are more accurate than the throwing performance of actors. Visual search behavior, cortical activity, and cellular phone use on driving performance Murray, Nicholas; East Carolina University Driver distraction is a high priority topic for the U.S. National Highway Traffic Safety Administration (NHTSA). The major concern is that drivers will create potentially dangerous decisions about when to interact with in-vehicle technologies while driving. The NHTSA has long recognized the potential safety problems associated with in-vehicle technologies and driver distraction. As the number and availability of these technologies increases, so does the incidence of risky driver behavior. These factors increase the need for empirically based studies that assess the human behavior, device designs, and demands of the systems. The specific aim of this project was to evaluate the cognitive load utilizing electroencephalogram (EEG) and visual search behavior while driving under five driving conditions. Through the use of a driving simulator, we assessed changes in 40 volunteers’ visual search behavior as well as cognitive demands under five driving conditions: no distraction, two levels of cognitive demand with a hand-held phone, and two levels of cognitive demand with a hands-free phone. It was demonstrated that an increase in cognitive load as produced by cellular phone use produced more erratic visual search behavior and an increase in EEG activity. The results are discussed in terms of Easterbrook’s cue-utilization theory. Nonlinear measures indicate gait variability is altered by peripheral arterial disease Myers, Sara A., University of Nebraska at Omaha; Nick Stergiou, University of Nebraska at Omaha and University of Nebraska Medical Center; Jason Johanning, Iraklis I. Pipinos; University of Nebraska Medical Center and Nebraska Western Iowa Veterans Affairs Medical Center; Shing-jye Chen, University of Nebraska at Omaha; Dan Blanke, University of Nebraska at Omaha and University of Nebraska Medical Center Peripheral arterial disease (PAD) is a manifestation of atherosclerosis that leads to a decrease of blood flow to the legs, resulting in cramping pain known as intermittent claudication. PAD leads to reduced mobility and poor health outcomes, including increased risk of falls. The majority of PAD patients are elderly (Hirsch, 2001). Increased gait variability has been associated with falls during walking, especially in the elderly (Brach, 2005). Thus, our goal was to investigate gait variability in PAD patients. Nineteen patients and 17 controls walked on a treadmill while kinematics were captured at their self-selected speed; in patients prior to the onset of pain. Relative joint angles were calculated for the ankle, knee, and hip and
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the largest Lyapunov exponent (LyE) was calculated for each trial with at least 30 footfalls. Student t tests were used to compare gait variability between groups. PAD patients had significantly higher LyE for all joints. Thus, gait variability is altered at all three joints in the PAD patients even before the onset of claudication pain. Variability is recognized as a reflection of overall health of the system and an indicator of motor control (Stergiou, 2006). Gait variability changes occur prior to the onset of claudication, which agrees with previous studies suggesting that an underlying abnormality exists in the muscle bioenergetics of PAD patients (Pipinos, 2006) and interferes with the cooperative strategies of the neuromuscular system. Collectively these results indicate decline of overall health of the system due to increased noise in the neuromuscular system, which possibly contributes to falls and mobility problems in PAD patients. This work was supported by NIH K25HD047194, NIDRR H133G040118, Nebraska Research Initiative, American Geriatrics Society’s Dennis W. Jahnigen Award, and the American Heart Association. Advanced cue utilization and anticipation of soccer players Nagano, Tomohisa; Takaaki Kato, Keio University It has been widely demonstrated that experts are better than novices at using advance visual cues to guide anticipatory responses (Abernethy, 1987; Williams & Burwitz, 1993). Previous studies analyzed visual search behaviors in various situations (Williams & Davids, 1998; Nagano et al., 2004). However, visual orientation may not be directly related to information extraction. The purpose of this study was to investigate the differences in the ability of soccer players to anticipate the direction of kicks. In particular, temporal and spatial occlusion paradigms were used in this study to examine anticipatory cue usage. First, we used a motion analysis system to capture the kinematics of the kicker’s motion from the start of the run-up until the end of the follow-through; next, we created stick figure animations for the following five conditions of spatial occlusion: (A) no occlusion, (B) lower body, (C) upper body, (D) non-kicking side of the body, and (E) kicking foot side of the body. Eight experienced soccer players and eight novice counterparts participated in this study. The participants were required to indicate, by a verbal response, the corner of the goal toward which the ball would be directed. The kicker’s kicking motion, which was displayed with the aid of stick figure animations, was occluded at the following four sequential points: beginning of the run-up (P1), setting down of the non-kicking foot (P2), ball-foot contact (P3), and the end of the follow-through (P4). The results indicated that experienced players were better at anticipating the direction of the ball than were novices. This suggests that experienced players possess the ability to anticipate and extract advanced information from a limited gaze area. The temporal and spatial occlusion paradigm used in this study may prove to be a more effective method in determining advanced cue usage in sport. Memory-guided reciprocal aiming movements are subject to compression of visual space Neely, Kristina A.; Haylie Douglas, Jessica Ridley, Matthew Heath; University of Western Ontario Previous work (Heath & Binsted, 2007) has demonstrated a compression of space for discrete memory-guided pointing movements. Specifically, Heath and Binsted revealed a consistent pattern of overshooting and undershooting characterizing reaches directed toward and away from the body, respectively. The goal of the present work was to evaluate the time frame by
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which compression of space is amplified in visuomotor memory. To that end, participants completed reciprocal aiming movements, toward and away from the body, for 10 s in two visual conditions (limb visible, limb occluded). In limb visible trials, participants had vision of their limb throughout the trial, whereas in limb-occluded trials vision of the limb was removed concurrent with response cuing. In both conditions, targets remained visible for the first 2 s of a trial, after which they were occluded. We used three pairs of targets aligned with body midline, giving rise to movement amplitudes of 14, 18, and 22 cm. In accord with earlier work (Binsted et al., 2006), we observed an increase in end-point variability as a function of time; that is, variability accumulated continuously following target occlusion. Counter to our expectations, however, we observed a reliable pattern of overshooting for the 14- and 18-cm movement amplitudes. Specifically, participants overshot veridical target location in all combinations of reaching direction (toward, away) and movement amplitude (14, 18, 22 cm) with one exception; reaches toward the body in the 22-cm movement amplitude condition elicited a reliable pattern of undershooting. Interestingly, the general pattern of overshooting was attenuated over time, such that there was a gradual decrease in overshooting error over the course of the trial. These results suggest that after target occlusion, participants controlled their aiming movements via an allocentric representation of target location. Further, the reduction in overshooting as a function of time suggests this allocentric representation was subject to compression of visual space. Supported by NSERC Force variability and Down syndrome Ofori, Edward; Kevin S. Heffernan, Jacob J. Sosnoff, Tracy Baynard, Jeffrey A. Woods, Bo Fernhall, University of Illinois at Urbana-Champaign Motor variability is elevated in individuals with Down syndrome (DS) compared to persons without DS. This greater variability is similar to that seen with normal aging. Since it is well established that persons with DS age prematurely, accelerated neural aging in DS may contribute to more variable force output as is seen with healthy aging. The purpose of this study was to examine the structure in both time and frequency domains of force output variability in persons with DS in order to determine if deficits in force control are similar between individuals with DS and older adults. An isometric handgrip task at a constant force 30% of maximal voluntary contraction was completed by individuals with DS (n = 29, age 26 years), and healthy young (n = 26, age 27 years), and older (n = 33, age 70 years) individuals. Mean, SD, coefficient of variation (CV), spectral analysis, and approximate entropy (ApEn) were used to analyze the magnitude and structure of force output variability. Mean force output for DS was lower than in young controls, p < 0.5, but no different from old controls. Individuals with DS had greater SD and CV than young and old controls, p < 0.05. The DS group had a significantly greater proportion of spectral power within the 0–4 Hz bandwidth than the young and old controls, p < 0.05. The DS group had significantly lower ApEn values than the young controls, p < 0.05, but there were no differences in ApEn between the DS group and the old controls, p > 0.05. In conclusion, individuals with DS demonstrate enhanced temporal structure and greater low-frequency oscillations in the force output signal than age-matched non-DS peers. Young persons with DS have similar timedependent structure of force output variability when compared to older persons without DS, despite similar mean force output, suggesting a link between the aging process and the loss of complexity in force output.
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The relationship between discrete and continuous force variability Ofori, Edward; Jacob J. Sosnoff, Les G. Carlton; University of Illinois at Urbana-Champaign The purpose of this investigation was to examine the relationship between discrete (between trial) and continuous (within trial) force variability in isometric force production. Participants performed both discrete and continuous tasks with the elbow flexors at 7 absolute force levels (30 N, 45 N, 60 N, 75 N, 90 N, 105 N, and 120 N). In the discrete protocol, participants performed 70 trials with a time to peak force criterion of 200 ms at each force level. In the continuous force protocol, participants performed 4 trials at each force level with trial duration of 15 s. Dependent measures computed for the discrete protocol were between trial mean (M) and standard deviation (SD) of force output. The dependent measures computed for the continuous protocol were within trial M and SD of force output. Findings indicate discrete and continuous absolute force variability (SD) increased with increases of force level for both protocols. A moderate significant relationship between discrete and continuous force variability was found (r = .35). This suggests that similar control processes may modulate force variability in discrete and continuous force production tasks. Manipulations to the timing and attentional focus of instructions to examine the reinvestment hypothesis of skill learning Ong, Nicole T.T.; Alison Bowcock, Nicola J. Hodges; University of British Columbia There is evidence that prescriptive versus discovery methods of learning can lead to breakdowns under pressure due to “reinvestment” of knowledge (e.g., Masters & Maxwell, 2004). There is some speculation that this breakdown is mediated by the attentional focus of the instructions. We expected these effects to also be mediated by the timing of the instructions. Three groups practiced a forehand disc-throwing task and we manipulated the timing and content of instructions two groups received technical instructions on the first day. Instructions were matched for content but differed in the attentional focus (1 = internal, body-related; 2 = external, disc-related). A third group only received internal instructions on a second day (n = 10/group). Measures of form and target error were examined in retention and under evaluative conditions (i.e., pressure). Both types of instructions led to improvements in movement form on Day 1 compared to no-instructions. However, all groups showed improved accuracy across practice (p < .01) and it was the no-instruction group who was the most accurate (significantly different to the internal group only). In retention, the error scores were similar for the three groups. Under pressure, the external instruction and no-instruction groups’ error was significantly reduced, whereas the internal instruction group did not make any improvements. All three groups showed a reduction in error on Day 2 of practice, although there were no group differences. The form scores of the internal, Day 2 group improved to match that of the other 2 instruction groups. There was Group × Condition interaction when error scores on the delayed retention test were compared to the pressure condition (p < .05). Only participants who received internal instructions on the first day showed an increase in error under pressure. There is evidence that both the timing and attentional focus of instructions impacts performance under pressure and that these factors interact. Further testing is underway of a Day 2, external instruction group to balance the design.
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Aging and manual asymmetries in fine motor performance Painter, Richard; Wilfrid Laurier University; William Oud, Eric A. Roy, Genevieve Desmarais, Vessela Stamenova; University of Waterloo; Pamela Bryden, Wilfrid Laurier University Studies investigating age differences in manual asymmetries have found that performance declines with age (Williams, 1989) with some studies finding the preferred-hand advantage remains unchanged with age (Chua et al., 1995), whereas others (Francis & Spirduso, 2000) found a decrease with age only for their most complex motor task, the Purdue pegboard. In this study, we examined performance on the Annett pegboard, which required participants to move ten pegs from one set of holes to another as quickly as possible. Groups of young (N = 60, 20–25 years) and older (N = 22, 75–85 years) right-handed adults performed five trials with each hand. This task was similar to the Purdue pegboard, which in the Francis and Spirduso (2000) study showed a decreasing preferred-hand advantage with age, so we predicted a similar result. The analysis revealed the expected effects for hand and age, with the preferred right hand and the young adults making the ten peg movements in less time than the nonpreferred left hand and the older adults, respectively. The Predicted Age × Hand interaction was not found, indicating that the preferred hand advantage did not decline with age. This lack of an age effect may have been due to two important differences between the pegboard tasks, the number and size of the pegs with the Annette pegboard having fewer and larger pegs. These differences may have lead to a decreased demand being placed on fine motor control in the Annett pegboard, which may explain the lack of change in the preferred-hand advantage with age. Our future work will examine these demands using the grooved pegboard where we have shown (Bryden & Roy, 2005) in young adults a greater preferred hand advantage when placing the pegs (place task) in the holes than when removing them from the holes (remove task). Based on these findings we would predict a decline in the preferred-hand advantage only on the more demanding place task. The implications of these findings for understanding the effects of aging on manual asymmetries in fine motor control will be discussed. On-ice spatial occlusion in elite ice hockey goaltenders Panchuk, Derek; Joan N. Vickers, University of Calgary Previous research examining the gaze behaviors of elite goaltenders revealed that goaltenders allocate 72% of their fixations on the puck as the shot is executed, with very few fixations to other parts of the shooter’s actions or the environment (Panchuk & Vickers, 2006). While providing insight into the nature of the visual cues used during fixation, the methods used precluded ruling out goaltenders using peripheral visual information from the shooters body to help aid their performance. In the current study we used a novel screen device that allowed portions of the shooter’s body and stick to be selectively occluded while allowing the puck to travel through it without affecting its speed. Eight (N = 8) elite goaltenders attempted to stop shots taken by shooters from 10 m while wearing an eye tracker (Mobile Eye, ASL) coupled to a high-speed camera that recorded the goalie’s movements. Shots were taken under five different occlusion conditions: no occlusion, stick, upper body, lower body, and total occlusion, where only the final puck flight was visible. Conditions were randomized and 35 shots performed per condition. Significant performance differences were found due to condition, as measured by save percentage number of saves/total shots taken. Save percentage was highest in the no occlusion condition (83.2%), followed by the lower body (80.5%), and upper body (79.7%) conditions. When the puck and stick areas were occluded,
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there was a drop-off in performance as observed in the total occlusion (70.4%) and stick occlusion (63.9%) conditions. These results suggest that goaltenders do not rely on peripheral information from the shooters body in order to make saves. Rather they use visual information from the puck on the stick as the shot is executed. These results are supported by the goaltender’s gaze data, which showed that even when the puck and stick were occluded by the screen and the shooter’s body was visible, they fixated on the screen rather than on the movements of the shooter. Increased recruitment of the ipsilateral sensorimotor cortex and coherence during multi-joint, goal-directed arm movements Pangelinan, Melissa M.; Florian A. Kagerer, Bradley D. Hatfield, Jane E. Clark; University of Maryland Increased ipsilateral activation and interhemispheric coherence has been reported for movements of the nondominant compared to dominant hand, suggesting the need for additional neural resources for accurate motor performance (Serrien, Cassidy, & Brown, 2003). Few studies, however, have investigated differences in asymmetry and functional networking during multi-joint, goal-directed movements typical of everyday motor behavior. The purpose of this study was to characterize differences in electrocortical dynamics and movement kinematics involved in planning and performance of the dominant and nondominant hands during movements involving multi-joint coordination and high movement accuracy. Fifteen adults performed a center-out drawing task with the dominant and nondominant hands. Sixty movements were made for each hand to one of two peripheral targets from a center position. Targets and online visual feedback were provided on a computer monitor. The movements were self-selected, self-initiated, and participants were instructed to move straight, quickly, and accurately to the target. Movement kinematics and electroencephalography was recorded from 9 cortical sites (F3, Fz, F4, C3, Cz, C4, P3, Pz, and P4) during task performance. Movement-related cortical potentials and coherence were analyzed along with movement kinematics. The behavioral results show increased root mean squared error, variability in initial direction error, and movement length for the movements of the nondominant hand. The results from the coherence and motor cortical potentials revealed increased coupling and ipsilateral activation during nondominant compared to the dominant hand performance. These results indicate that the increased task difficulty lead to behavioral decrements in performance and the recruitment of additional neural resources during planning and performance of the nondominant hand. In comparison, dominant hand performance is characterized by both efficient neural recruitment and kinematics. This research was supported by NIH R01HD42527 (JEC) and NIH RO3HD050372 (FAK). Load and effector transfer in movement sequence learning Panzer, Stefan; University of Leipzig; Charles H. Shea, Texas A & M University; Thomas Muehlbauer, University of Basel; Melanie Krueger, University of Leipzig Actual experiments have demonstrated that a movement structure develops in the course of learning a sequence that provides the basis for transfer. The structure is composed of concatenated subsequences that can be executed relatively seamlessly after considerable practice. Importantly, after developing a movement structure, participants have been shown to be able to effectively rescale the sequence when movement demands require increases or decreases of force or when the sequence must be produced with an unpracticed set of
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effectors. One aspect of sequence production that has not been systematically studied, however, is the question of whether the scaling of forces of a movement is limited to the effector used for practice. In two experiments, loads were used to determine the transfer profiles of movement sequences to a practiced and an unpracticed limb. Experiment 1 was conducted to determine whether participants, after learning a complex 16-element movement sequence with a 0.56-kg load with their dominant right limb, could also effectively produce the sequence when the load was decreased (0.0 kg) or increased (1.13 kg) with the practiced and the unpracticed nondominant left limb. Experiment 2 differed with the exception that participants practiced the sequence with their nondominant left limb. Results of both experiments indicated that participants were able to effectively compensate decreased and increased loads with virtually no changes in performance characteristics (displacement, velocity, acceleration, and element durations) with the practiced and the unpracticed limb as long as the sequence structure is held constant. EMG signals in retention and transfer tests demonstrated that regardless of the limb used for practice, the level of coactivation of the practiced limb was always lower, compared to the unpracticed limb. This suggests that the movement structure developed with practice, and the rapid adaptation to different loads reflects a capacity to rescale movement sequences when movement demands are changed, regardless of the limb used for practice. Workload stress and stimulus-response compatibility: Effects on response latencies in a choice reaction time task Park, Andrew; Florida State University; David D. Chen, California State University– Fullerton Stimulus-response (S-R) compatibility effects refer to the phenomenon where certain mappings of stimuli to responses produce faster and more accurate responses than others. Increased latencies are attributable to a decreasing attentional resource pool as well as stress symptoms. The primary purpose of this study was to examine the effects of levels of workload stress through the addition of a dual task on the accuracy and speed of choice reaction time (RT) performances varying in spatial and anatomical stimulus-response compatibility. A secondary purpose was to determine if there was association between increased RT latencies and indices of stress, i.e., heart rates and self-reported anxiety scores. Fifty undergraduate students were randomly assigned to one of the two groups: the single-task condition and the dual-task condition. Each participant completed 160 trials that were spread out across four different stimulus-response compatibility conditions that were quasi-randomly presented. Dependent variables included latencies in choice reaction time, error scores, average heart rates, and pre- and post-scores of the modified POMS. Results supported the previous findings of S-R compatibility. The dual task consistently produced longer latencies than the single task condition and more direct mappings stimuli to response led to faster latencies. In addition, a sex effect and crossed-hand effect were identified. Males were faster and more accurate than females when the spatial S-R compatibility was low and workload stress was high. The hypothesized connection between increased response latencies and stress symptoms was not identified, suggesting that the increased response latencies were attributable more to a decreasing attentional resource repertoire than to the interference of increased sympathetic output. Investigating the role of task duration and feedback frequency on the acquisition and retention of a time estimation task Parry, Thomas E.; Bill R. Wyatt, John B. Shea; Indiana University
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Relative frequency of KR has been a major topic in motor learning, with a variety of studies investigating its role in the performance and learning of motor skills (Montare, 1985; Salmoni et al., 1984). Previous research has compared a 100% relative frequency with a lower relative frequency such as 33% (Ho & Shea, 1978). However, little research has investigated the interaction of relative frequency and task duration on the performance and learning of a simple motor skill. The purpose of this study was to investigate the interaction between KR schedule and task duration. Specifically, are there task durations where KR is no longer beneficial? Subjects were asked to complete a three-key button-pressing sequence at one of three target times. Subjects performed 48 acquisition trials, followed by a 6-min filled retention interval, then 12 no-KR retention trials. During acquisition subjects were assigned to a 100% or 33% KR relative frequency and target time of 750 ms, 2,750 ms, or 7,250 ms. A kernel regression analysis was used to compare error across feedback and timing conditions. The analysis showed significant differences for both feedback frequency, F(1, 282) = 136.3, p < .001, and time F(1, 282) = 56.0, p < .001. For 100% feedback minimum error was reached by Trial 19 for 750-ms and 2,750-ms tasks. Minimum error for the 7,250-ms task was not reached until Trial 35. The findings were similar for the 33% feedback group, except minimum error was reached later in the task, after Trial 25 for 750- and 2,750-ms groups and not until Trial 43 for the 7,250-ms group. This finding supports previous research on the role of feedback during acquisition of a task (Salmoni et al., 1984). A 2 × 3 Frequency × Time ANOVA performed on the retention trials showed time, F(2,288) = 26.5, p < .001, and the time by feedback interaction, F(2,288) = 4.813, p = .009, to be significant. In both feedback conditions, error increased as task time increased. This suggests that length of time has a greater effect on error rates than frequency of feedback. Cervical spine movement and Fitts’s task performance after spinal manipulation Passmore, Steven R.; McMaster University and New York Chiropractic College; Jeanmarie Burke, New York Chiropractic College; Christopher J. Good, University of Bridgeport; Jim Lyons, McMaster University; Andrew S. Dunn, New York Chiropractic College and VA Western NY Spinal manipulation (SM) is a common manual therapy intervention primarily used to affect joint motion and pain. Presently a paucity of research examining quantifiable effects of SM on motor performance exists. This study investigated head movement time (MT) differences between participants who received high velocity, low amplitude upper cervical SM or no intervention (NI). A previously established computer-aided head movement task that has replicated Fitts’s movement paradigm was used under varying conditions of amplitude (50, 100, and 200 mm) and target width (5, 7.5, and 11.25 mm) to create nine indexes of difficulty (IDs). Inclusion criteria required participants to have an asymptomatic palpable intervertebral motion restriction at the C1-C2 level (n = 15). Cervical spine active range of motion (AROM) and premanipulation Fitts’s tasks of rightward and leftward movements were measured. Participants were then randomized to a SM group (n = 8) or NI group (n = 7). Cervical spine AROM was repeated, as were Fitts’s task trials. Those with bilateral joint restrictions were excluded from MT analyses so direction of joint restriction could be compared to task rotation. The experimenter who measured the Fitts task was blinded to randomization. In the SM Group AROM into rotation increased after the intervention (pre: M = 74.75°, SD = 7.63°; post: M = 78.5°, SD = 7.23°; t(8) = −3.07; p = .018). Significant Group × ID interactions were present in the SM Group for MT in direction congruent conditions, F(8, 48) = 2.83; p < .05, and direction incongruent conditions, F(8, 48) = 2.31; p < .05, but not for the NI group, revealing that pre-SM ID impacted MT more than post-SM. A linear
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relationship between ID and MT as predicted by Fitts’s law was observed. Significant Group × ID interactions indicate that SM not only increases cervical AROM, but also facilitates the performance of a cervical spine Fitts task requiring rotation. This task may in the future be extended to quantify motor performance in clinically symptomatic populations with reduced ROM who are appropriate candidates for SM. Vision and target size effects on locomotor pointing Popescu, Adrian; Keith Runnalls, James Chevalier, Vance Pilipchuk, Brian Maraj; University of Alberta Interceptive tasks occur frequently during both daily and sport activities. One particular form of interceptive tasks is locomotor pointing: the motor act of precisely positioning the targeting foot about a specific location (e.g., climbing stairs, take-off phase in long jumping). However, the input of target size on locomotor pointing accuracy has not been explored in such contexts. The purpose of our study was to observe the influence of vision availability during the gait cycle on pointing accuracy for two different target sizes, 120 in2 vs. 60 in2. Seven male undergraduate students volunteered for the experiment. They were independent walkers with normal or corrected to normal vision. Participants were required to walk at a self-selected pace towards targets located 5 m away. Three visual conditions were presented using a pair of Plato LCD goggles (Translucent Technology, Toronto, ON). The conditions were full vision, vision during the swing phase, and vision during the stance phase of the gait cycle. Participants performed 5 trials for each visual and target size condition for a total of 30 trials. Experimental conditions were presented in a randomized fashion. A PTI Visualeyez motion analysis system (PTI, Burnaby, BC) was employed to capture kinematic data of the lower leg at a sampling rate of 125 Hz. Vision availability was regulated using two force-sensitive resistors (FSRs, National Instruments, Inc.) mounted on the shoe sole of the targeting foot at the heel and ball of the foot. The FSRs were wired to, and changed the status of, the goggles from transparent to translucent and vice versa as a function of the gait cycle. Data were analyzed using a 3 (vision) × 2 (target) repeated measures ANOVA. Results indicate a significant main effect of target size, F(1, 6) = 14.51, p = .009, with participants overshooting the small target and undershooting the larger one. These results will be discussed as they relate to visual control of locomotor pointing and the influence of the index of difficulty as a function of the target sizes. Systematic increases in contextual interference is beneficial for learning tasks controlled by different generalized motor programs Porter, Jared M.; Louisiana State University; Richard A. Magill, New York University Historically, contextual interference (CI) has been investigated by comparing schedules offering fixed amounts of CI during practice, namely blocked and random scheduling. This experiment investigated a new method of using CI in practice. The primary purpose of this experiment was to test the hypothesis that a practice schedule with systematic increases in CI would lead to superior performance compared to schedules that offer fixed amounts of CI, i.e., blocked and random. The secondary purpose was to compare these practice schedules for learning three tasks controlled by different generalized motor programs GMP. The participants (N = 96), college females who had no experience playing basketball, practiced three different basketball passes: a two-hand chest pass, a two-hand overhead pass, and a single-arm pass. All participants passed the ball to a wall target 5 m away and were instructed
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to hit the center of the target on each pass. The passes were practiced for a total of 81 trials. The blocked and random schedule groups practiced each pass for 27 trials each following traditional schedules. The increasing schedule group practiced the first 27 trials in a blocked schedule, then 27 serial trials, and then 27 trials of random practice. On the following day, participants completed a 12-trial retention from the same line as practiced and transfer from a line 6 m from the target test. Results absolute error, absolute constant error, and variable error showed that all three groups significantly improved during practice, with the increasing and blocked groups performing significantly better than the random group at the end of practice. Posttest results showed that the increasing group performed significantly better than the blocked and random groups on the retention and transfer tests. Concurrent feedback and learning: Insights from variability of degrees of freedom Ranganathan, Rajiv; Karl M. Newell, Pennsylvania State University The study examined the influence of augmented feedback on the learning of a task with redundant degrees of freedom. Participants were asked to produce discrete pulses of force with two fingers such that the peak of the total force was 10 N. Participants were randomly assigned into one of four different groups: (a) a 100% KR group that received knowledge of results (KR) about the total peak force at the end of each trial, (b) a 50% KR group that received KR on every alternate trial, (c) a concurrent feedback group (ConFB) that received instantaneous information about the total force they were producing during the trial, and (d) a concurrent feedback group with knowledge of No-KR test (ConFB_Test Info) that received the same information as the ConFB group, but were informed about the No-KR test in advance. Participants performed 8 blocks of 60 trials followed by a No-KR test in which they received no visual feedback. The coordination strategies were analyzed using the uncontrolled manifold analysis, which partitions the total variance of the peak force between trials into variance along and orthogonal to the manifold, F1 + F2 = 10. The results showed that the ConFB group had the smallest errors during acquisition but the largest errors in the No-KR transfer test. The analysis of the coordination strategies showed that there was a tendency only for the ConFB group to use different solutions from trial to trial to achieve the goal. Further, when the error on each trial was correlated with the changes in the individual finger force on the next trial, the ConFB group showed the least correlation. These results suggest that one reason why concurrent feedback hampers learning is that it facilitates the utilization of multiple solutions for achieving the goal during acquisition. This “many-to-one” mapping interferes with the formation of an association between the task outcome and the individual degrees of freedom, which may be adaptive when concurrent feedback is available but is maladaptive when feedback is removed. Vision affects balance control during quiet stance in multiple sclerosis Remelius, Jebb G.; University of Massachusetts; Linda Chung, Jane Kent-Braun, Richard van Emmerik; University of Massachusetts–Amherst MA Common symptoms of multiple sclerosis (MS) include poor balance control, visual impairment, and fatigue. Prior research on balance control during quiet standing in people with MS has shown increased center of pressure (CoP) sway (Remelius et al., 2005). Standing with eyes closed affected CoP sway similarly in healthy controls and people with MS. The purpose of the current investigation was to assess the effects of vision on dynamic measures of postural control in the CoP and center of mass (CoM) during quiet standing in MS. These
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measures include CoP and CoM velocity, time to contact to the stability boundary, as well as asymmetry of lower limb loading. Ground reaction forces from two force platforms and 3-D kinematic data were collected from 12 women with MS (age: mean 55.6, SD 9.7) and 12 healthy women (age: mean 53.0, SD 9.2) during quiet standing with eyes open and with eyes closed. Expanded Disability Status Score (EDSS) in the MS group ranged from 2.0 to 6.0 (median = 4.0). CoP and CoM data were derived from the ground reaction force and 3-D kinematic data. In comparison with controls, MS participants exhibited greater sway amplitude (quantified as standard deviation of displacement) in CoP (CoP_ML p = 0.026; CoP_AP p = 0.016) and CoM (CoM_ML p = 0.022; CoM_AP p = 0.041), as well as higher CoM velocity (p = 0.024). Time to contact (TtC) to the stability boundary was shorter in MS compared to controls (CoP_TtC p = 0.023; CoM_TtC p = 0.016). Vision did not effect CoP or CoM displacement, but higher velocities in the CoP (p < 0.001) and CoM (p = 0.013) and shorter TtC (p < 0.001) occurred with eyes closed across groups. Withdrawal of vision affected the MS group more than the control group for limb loading asymmetry (p = 0.008) and CoP_vel (p = 0.032). The results from this experiment indicate changes in postural control in MS on the basis of CoP and CoM velocity and time to contact information. Even in quiet standing conditions there may be increased reliance on the visual system for balance control in people with MS. Support: PP0934; National Multiple Sclerosis Society. The role of cognitive effort in blocked and random practice of applied motor skills Rendell, Megan; Australian Institute of Sport and Victoria University; Damian Farrow, Australian Institute of Sport; Rich Masters, University of Hong Kong; Tony Morris, Victoria University A consistent finding in motor learning research is that the high level of contextual interference (CI) imposed by a random practice protocol leads to more effective learning outcomes than blocked practice. According to the elaboration (Shea & Zimny, 1983) and reconstruction (Lee & Magill, 1985) hypotheses, the CI effect results from enhanced cognitive effort stimulated by random practice. Research evidence supporting a difference in cognitive effort during high and low CI practice is limited and has centered on laboratory-based tasks (Li & Wright, 2000). The current study extended previous work by examining the cognitive effort of high and low CI practice in two applied sports skills (kicking and handball passing in Australian Rules football). Novice participants were assigned to either a blocked (n = 9) or random (n = 10) practice condition. Participants completed 320 acquisition trials of each football skill over a series of 7 training sessions. A probe reaction time (PRT) procedure was used during acquisition to assess cognitive effort. Posttesting was conducted immediately following the final acquisition session, and retention testing took place after a 5-week interval. The accuracy scores of both groups improved significantly during acquisition (kicking: F(4, 66) = 5.58, p < .05; handball passing: F(3, 54) = 7.76, p < .001), in the absence of any significant group or interaction effects (both p > .05). The random practice group demonstrated greater retention of skills, performing more accurately than the blocked group on the kicking task at retention (p < .017), but not on the pre- or posttests (both p > .017). PRT results revealed that the random group responded significantly more slowly to the probes than the blocked group during acquisition, F(1, 14) = 4.65, p < .05, supporting the hypothesis that high CI practice is associated with higher cognitive effort. The findings will be discussed in relation to the role of cognitive effort in CI and the apparent discrepancy between field and laboratory-based studies.
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Timing in tapping and circle drawing is related in long time series Rheaume, Nicole L.; Purdue University; Howard N. Zelaznik, Purdue University A distinction has been made between the timing of discrete movements and the timing of continuous movements (Ivry, Spencer, Zelaznik, & Diedrichsen, 2002; Robertson et al., 1999). In a recent study, Rheaume, Lemoine, Balasubramaniam, and Zelaznik (in preparation) provided evidence suggesting that there could be a shared timing component between tapping (discrete) and circle drawing (continuous). The structure of the variability of the time series was examined using spectral analysis, and a 1/f slope was found in the low frequency region of the spectral plot for both tapping and circle drawing. In order to support the idea that the similar spectral slope for tapping and circle drawing is evidence of a shared timing component, the individual differences in spectral slopes needed to be examined, which was the goal of the current study. Participants performed tapping and circle drawing continuation timing tasks over two days (90 min each day). The goal cycle duration was 500 ms, and each trial lasted about 5 min so that at least 512 usable intervals were produced. Spectral analysis of the time series was used to compute the 1/f slope for each task. A negative slope was found for both tapping and circle drawing, replicating the finding of Rheaume et al., but the reliability of the slopes was low. Furthermore, individual difference correlations between tapping and circle drawing 1/f slopes were not significantly correlated. However, the coefficient of variation (CV) between tapping and circle drawing was significantly correlated. Previous timing work has never found a significant correlation of CV between tapping and circle drawing, although those experiments used much shorter time series. When the first 30 intervals of our 512 interval time series were examined, a significant correlation between tapping and circle drawing was still found. These results lead us to believe that participants adopt a different timing strategy when they know they are to produce intervals for an extended period of time. Parallel activation of implict and explicit system in observational learning Rhee, Joohyun; Texas A&M University; Kirk A. Zihlman, Department of Veterans Affairs Medical Center–Houston; David L. Wright, Texas A&M University Willingham & Goedert-Eschmann (1999) proposed that implicit and explicit knowledge developed simultaneously but suggested that physical practice is necessary for the parallel activation of both systems (Willingham, 1999). The present experiment used an observational learning paradigm to evaluate this proposal. Individuals were trained in pairs, with one participant being assigned to physical practice of a serial reaction time (SRT) task and the other as an observer. Each pair was further assigned to either an implicit or explicit learning condition. The explicit condition involved the receipt of detailed instructions about the sequential nature of the task. Pairs in the implicit condition did not receive these instructions but were told to execute key strokes as quickly and accurately as possible. All physical practice and observers were provided retention tests to assess the development of implicit and explicit knowledge following practice. Mean reaction time for the practiced and a novel sequence at retention was compared to estimate acquired implicit knowledge. Free recall of the sequence was used to estimate explicit sequence knowledge. Performance of the individuals administered physical practice indicated parallel activation of implicit and explicit systems. The performance of the explicit group of observers also showed similar parallel activation of implicit and explicit system, which would be unanticipated if physical practice is necessary to trigger the involvement of the implicit learning system.
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Visual instructions benefit adults with Down syndrome in continuous bimanual and unimanual drumming Ringenbach, Shannon D.; Chih-Chia Chen, Arizona State University The present study examined bimanual and unimanual, continuous and discrete drumming in response to different instructions in 20 adults with Down syndrome, 20 mental age-matched, and 20 chronological age-matched groups. The drumming task required participants to hit either one or two drums with drumsticks following verbal (e.g., “up” and “down”), visual (e.g., video of drumsticks moving up and down together), and auditory (e.g., sound of drums being hit, then cymbal being hit) instructions for either 10 s (e.g., continuous) or one hit (e.g., discrete). In general, discrete movements were performed straighter and faster than continuous movements. Unimanual movements were faster than bimanual and unimanual continuous movements were more curved than bimanual continuous movements. Adults with Down syndrome and MA produced straighter and shorter movements when following visual instructions in continuous movements, whereas there were no differences with instruction type in discrete movements. In addition, it appears that adults with DS performed best in the least complex situations (e.g., unimanual, discrete). Gesture imitation in corticobasal syndrome: Translating visual-gestural information into action Roy, Eric A.; University of Waterloo; Vessela Stamenova, University of Toronto; Sandra E. Black, Sunnybrook Health Sciences Centre; Mario Masellis, University of Toronto; Quincy Almeida, Wilfrid Laurier University Corticobasal syndrome (CBS) is a neurodegenerative condition in which limb apraxia is the most common cortical deficit. Apraxia is often assessed comparing pantomime (performing gesture from memory) with imitation. Healthy age-matched adults usually perform better on imitation than pantomime. Our work (Stamenova et al., 2006) with CBS patients has found that they do not show this advantage for imitation, but rather perform at the same level as pantomime. Thus, relative to controls, their performance on imitation is worse. According to Roy’s model (Roy, 1996; Roy et al., 2000) their poorer performance at imitation could indicate a problem in analyzing the visual gestural information in the examiner’s demonstration of the gesture or in translating this information into movement. This study was designed to dissociate between these processing stages in imitation. Participants (27 healthy age-matched adults and 7 patients with CBS) were required to imitate eight transitive (tool-use) gestures demonstrated by the examiner. Imitation was reflected in a composite accuracy score across five performance dimensions: hand posture, hand orientation, action, movement plane, and hand location. Participants also completed a gesture recognition task involving identifying each of the eight gestures from video demonstrations to assess their ability at visual gestural analysis. Relative to the healthy adults the patients exhibited significantly less accuracy only on the imitation task. CBS then does not appear to affect the first stage in imitation. Rather, the inability at imitation must arise from impairments in translating visual gestural information into movement. The implications of these findings for understanding apraxia in CBS will be discussed. EEG coherence during visuomotor performance: A comparison of corticocortical communication in experts and novices Saffer, Mark I.; University of Maryland; Sean P. Deeny, University of California, Irvine; Amy J. Haufler, Bradley D. Hatfield; University of Maryland
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EEG coherence was assessed to determine the relationship between corticocortical communication and visuo-motor skill in 15 expert and 21 novice rifle shooters. Coherence and phase angles between the prefrontal region (F3, F4) and ipsilateral cortical regions (central, temporal, parietal, and occipital) during the aiming period were calculated for the theta (4–7 Hz), low-alpha (8–10 Hz), high-alpha (11–13 Hz), low-beta (14–22 Hz), high-beta (23–35 Hz), and gamma (36–44 Hz) bands and subjected separately to a series of ANOVAs (Group × Hemisphere × Region × Epoch). Experts generally exhibited lower coherence compared to novices, with the effect most prominent in the right hemisphere. The groups also exhibited differences in phase angle in a number of frequency bands. Coherence was positively related to aiming movement variability in experts. The results support refinement of cortical networks in experts, and differences in strategic planning related to memory processes and executive influence over visual-spatial cues. The influence of visuomotor simulation training on arthroscopy performance Safir, Oleg; Eric Hagemann, Adam Dubrowski, David Backstein, Heather Carnahan; University of Toronto Background: Existing literature has shown benefit from the use of simulation for teaching surgical residents. However, it is unclear what aspects of the skill are actually being learned during simulation training. When expert surgeons are interviewed, they report that cognitive knowledge related to anatomy is the most important element to train during simulation to prepare a trainee to perform arthroscopy in an operating room. However, a task analysis of arthroscopy shows that other fundamental skills such as visual spatial and motor performance are critical, even though expert surgeons rank these abilities as being relatively unimportant. The purpose of this study was to assess whether basic visuospatial/motor simulation is beneficial for the performance of fundamental arthroscopy skills. Methods: One group of trainees practiced three visuomotor tasks on a laparoscopic trainer. These tasks included: peg transfer using graspers, precision circle cutting using scissors, and knot tying. A second group of trainees was not given the opportunity to practice these tasks. Then both groups performed a structure identification task on a simulated arthroscopy plastic knee model. This task involved using a probe to touch various locations within the knee. Time to completion and a task-specific time penalty score for mistakes were recorded. Results: Results showed that practice on the visuomotor tasks enhanced performance on the simulated arthroscopy task. That is, performance time was faster and more accurate when performing arthroscopy skills after practice on the visuomotor tasks. Conclusion: It is hypothesized that the automatic processing of the visuomotor aspect of the surgeons’ skills lead to their ranking of cognitive abilities over visuomotor abilities as being the most important aspect to train prior to entering the operating room. These results will be discussed in terms of specificity and transfer of training. Influence of different exercise approaches on motor symptoms in Parkinson’s disease Sage, Michael D.; Quincy J. Almeida, Wilfrid Laurier University Parkinson’s disease (PD) is a debilitating neurological disorder caused by degeneration of dopamine-producing cells in the basal ganglia. Treatment for PD involves dopamine replacement with the aim of decreasing symptoms. Exercise has been suggested to have a positive and potentially neuroprotective effect on PD, which could decrease dependence on medication. Research has also suggested that cuing strategies (Almeida et al., 2007) and
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focusing attention on movement performance (Lazarus et al., NASPSPA 2006) can have a positive impact on motor control in PD. The aim of this study was to determine how different exercises influence the motor symptoms of PD. The gold standard for clinical measurement of PD symptoms is the Unified Parkinson’s Disease Rating Scale (UPDRS). A trained clinician evaluates each symptom and rates it on a scale from 0 to 4, where higher scores represent more severe symptoms. In the current study, 56 PD participants were randomly assigned into one of three different exercise interventions: sensory attention focused training (SAFE) (M-15, F-7; age: 68.0 ±10.0); aerobic (M-7, F-6; age: 68.2 ± 9.7); strength (M-8, F-7; age: 69.7 ± 8.6) or a control group (M-4, F-2; age: 71.5 ± 11.8) that did no exercise. All participants exercised three times a week for twelve weeks followed by six weeks with no exercise (washout). UPDRS measurements by a blinded rater took place before and after 12 weeks of exercise, and also after the six-week washout. All medication and extraneous exercise was unchanged during the 18 weeks of observation. An Exercise (SAFE vs. aerobic vs. strength vs. control) × Time (0 vs. 12 vs. 18 weeks) ANOVA revealed a significant interaction, F(6, 104) = 3.51, p < .004. In contrast to controls, only the SAFE program (p < .002) resulted in significant UPDRS score improvement. Interestingly, the aerobic and SAFE programs appear to have a lasting effect according to washout data. Results will be discussed with respect to how and why the SAFE and aerobic exercise programs may be better suited for people with PD than strength training. Funding: Parkinson’s Society of Canada. Physical activity and intraindividual cognitive variability in children Samson, Jean M.; Jacob J. Sosnoff, Charles H. Hillman, University of Illinois Children are slower and more variable in their cognitive processing compared to young adults. It is maintained that children’s lower performance results from ongoing cortical organization during development, which has implications for the efficiency of their cognitive performance. Additionally, there is growing evidence that physical activity improves cognitive function in children. Currently, it is not clear if physical activity is associated with cognitive variability in children. In order to examine this gap in the literature, thirty-eight participants between the age of 8 and 11 years were divided into high-fit (HF, n = 19) and low-fit (LF, n = 19) groups based on the PACER test. A modified flanker task was used to assess interference control, one aspect of executive function. Each participant completed 312 trials equally divided into 6 blocks. The mean response time (RT), standard deviation (SD) of response time, and accuracy (percent correct) were calculated. Only correct responses were used in the RT analysis. Overall, there were no differences in mean RT and SD between HF and LF groups. However, the HF group was significantly more accurate than the LF group. The data were further analyzed to determine whether fitness influenced participants’ ability to manage perceptual interference. The LF group had lower interference scores for mean, accuracy, and SD of response time; however, these differences were not statistically significant. Overall, the findings suggest that accuracy of task performance is influenced by fitness in children; however, cognitive variability and mean cognitive functioning are unaffected, indicating that either the neurobiological mechanisms driving variability of cognitive processing in children are distinct from those of adult populations, or that differential mechanisms may be evident across the lifespan.
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Examining the effects of age on learner defined KR schedules for learning a two-part timing task Sanli, Elizabeth; Jae T. Patterson, Allan Adkin, Kinga Eliasz, Jenn Huffman, Brock University Learners afforded the opportunity to self-control a portion of their practice context has proven to be an effective strategy facilitating learning a novel motor skill. However, one area of limited inquiry is examining how the age of the participant interacts with learning effects associated with self-controlled practice contexts. The purpose of the present experiment was to examine the learning effects of younger and older adults afforded the opportunity to decide when they received knowledge of results (KR) during the acquisition of a two-part timing pattern. Two yoked conditions (one younger adult and one older adult) were also utilized where participants received KR on the same trials as their self-control counterparts, without the choice. During acquisition and retention, participants walked a 6-m straight pathway with the overall goal time alternating on trials between 80% and 120% of their preferred walking time. The first segment (2.5 m) of the pathway was to be completed in 32.5% of the total goal time, and the second segment (3.75 m) in 67.5% of the total goal time. During a transfer test, participants were required to complete the pathway in 70 and 130% of their preferred walking speed while maintaining the same segmental ratios. Our dependent variables of interest were absolute constant error The effect of different supra-postural task constraints on postural sway variability Saunders, Nichole E.; Michael A. Riley, University of Cincinnati Lightly touching a stable surface reliably reduces postural sway, even when mechanical support is negligible. Jeka and Lackner (1994, 1995) proposed that this occurs as a result of sensory information about body sway obtained from contact with the surface. An alternative hypothesis is that the reduction in sway variability represents facilitatory adjustments of postural control in response to the precision manual-control demands inherent in the task of lightly touching a surface (Riley, Stoffregen, Grocki, & Turvey, 1999). The goal of this study was to test contrasting predictions from these hypotheses by manipulating two constraints of light touching tasks: Force range (amount of variation tolerated in fingertip force production) and force level (the mean amount of force a person needs to apply to satisfy the task demands). We employed a factorial combination of two ranges (0.8 and 1.6 N) and two force levels (0.8 and 1.6 N). The sensory hypothesis (Jeka & Lackner) predicts the greatest reduction in sway would occur in the condition associated with the richest stimulation of cutaneous mechanoreceptors in the fingertip, which would correspond to a higher mean force level and a larger range, as the amount of fingertip pressure is proportional to mechanoreceptor discharge rate (Pubols, 1982).The supra-postural task hypothesis (Riley et al.) predicts, in contrast, that the greatest reduction in sway will occur when the precision demands of touching are greatest, which corresponds to the lower range, lower force level condition. Results indicated that differences between no-touch and touch conditions for anterior-posterior center of pressure range and maximum displacement were significantly affected by the force range manipulation, with a greater reduction in sway occurring for
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the 0.8-N range. This result is consistent with the sensory hypothesis—postural activity was differentially tailored to the precision demands of the touching task, and the largest reduction in sway occurred in conditions associated with presumably less rich fingertip mechanoreceptor stimulation. Cooperation between the limbs is better than we thought Shea, Charles H., John J. Buchanan, Attila J. Kovacs, Texas A&M University; Melanie Krueger, University of Leipzig The study of bimanual movements has been used as a window through which to discover how the nervous system self-organizes to accomplish specific behavioral actions (Kelso & de Guzman, 1988; de Guzman & Kelso, 1990). However, work by Mechsner (2001) has indicated that some of the difficulties participants experience producing bimanual movements arises from perceptual and attentional processing difficulties associated with typical testing conditions and are not exclusively the result of the inherent constraints of the motor system. The purpose of the present experiment was to observe the performance of participants attempting to produce 2:1 and 3:2 polyrhythms when attentional demands were reduced and feedback concerning the movement of the two limbs was integrated using a Lissajous plot. The task involved making continuous flexion/extension movements of the two limbs to produce the required polyrhythm. Participants could not see their limbs and feedback was in the form of a single dot tracing a Lissajous figure. We hypothesized that by reducing the processing and attentional demands typically associated with polyrhythmic behavior that participants would be able to effectively produce difficult rhythms with relatively little practice. The data from 14 participants indicated remarkably effective 2:1 and 3:2 performances after only 5 min of practice. The movement patterns of both limbs were continuous and harmonic. A frequency analyses indicated that a vast majority of power was within 0.1 Hz of the mean power frequency of each individual limb. This seems remarkable given that Summers, Davis, and Byblow (2002) have stated that “While a 2:1 ratio in a bimanual [finger] taping task is relatively easy to perform, producing the same ratio in tasks involving wrist or elbow oscillations where the limbs are moving continuously is extremely difficult.” These results are consistent with the notion that at least some of the difficulty typically associated with producing complex polyrhythms has been due to the perceptual and attentional demands imposed in various testing situations. Concurrent visual feedback reduces spatial errors in rapid continuous aiming movements Sherwood, David E.; University of Colorado; Kelly Klein, University of Colorado, Boulder The effect of concurrent visual feedback on continuous aiming movements was investigated in the preferred and nonpreferred hands of college-aged participants (n = 20). Participants made continuous rapid aiming movements with a lightweight lever in the sagittal plane over short 20° and/or long 60° distances. In different test conditions, participants either repeated the same distance either short or long or alternated the short and long movements. Participants performed 160 cycles in each test condition in 4 blocks of 40 cycles each. Concurrent visual feedback of the position-time trace was provided for the first 20 cycles of
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each block. The remaining 20 cycles were performed without visual feedback. The practice order of the short, long, and alternating conditions was randomized for each participant. Movement time was controlled by a metronome set at 1.43 cycles per second resulting in a cycle time of approximately 700 msec per movement. The constant error, variable error, and overall error in distance were calculated for each set of 20 cycles and analyzed with separate 2 (Hand: Preferred/Nonpreferred) × 2 (Condition: Same/Alternating) × 2 (Vision: Available/Not Available) × 4 (Set) ANOVAs with repeated measures on the last three factors. Movements were more accurate in the same condition compared to the alternating condition where the short movements were overshot and the long movements were undershot. The availability of visual feedback reduced constant errors in all conditions, particularly for the short distance in the alternating condition. Practice reduced constant errors in all conditions. The long movements were more variable than short movements, and vision improved variability, particularly for the short movements. Practice generally reduced variable errors. Overall errors generally followed the same trend as constant errors. The results suggest that the interference generated by alternating movement distances can be modulated by providing visual feedback. However, once the visual feedback is removed, interference effects appear immediately. Motor parameter value switching and spatial accuracy in discrete and continuous aiming movements Sherwood, David E.; University of Colorado Resent research has shown that reciprocal aiming movements were more accurate than discrete movements. However, in the earlier studies the index of difficulty was held constant over a given set of trials. The current experiment extended such work by asking the participants to change the movement distance from trial to trial or from cycle to cycle. College-aged participants (n = 20) made continuous or discrete rapid aiming movements with a lightweight lever in the sagittal plane over short (20°) and/or long (60°) distances. In different test conditions, participants either repeated the same distance or alternated the short and long movements. Participants performed 20 cycles or individual trials in each of 6 test conditions (long discrete, long continuous, short discrete, short continuous, alternating discrete, and alternating continuous). The practice order of the conditions was randomized for each participant. Movement time was controlled by a metronome set at 1.43 cycles per second resulting in a cycle time of approximately 700 ms. The constant error (CE), variable error (VE), and overall error (E) in distance were calculated for each set of 20 cycles or trials and analyzed with separate 2 (Distance: Short/Long) × 2 (Condition: Same/Alternating) × 2 (Type: Discrete/Continuous) ANOVAs with repeated measures on all factors. Alternating movements resulted in greater overshooting of the short movement and undershooting of the long movement compared to repeated movements. Discrete movements were less accurate and more variable than continuous movements, as expected. For E, alternating caused greater errors in the short movement compared to the long movement relative to repeated movements. The results confirmed the earlier results showing that continuous movements could be produced more accurately than discrete movements, even when movement distance must be varied from trial to trial or from cycle to cycle. The results also support recent neurophysiological evidence suggesting the control mechanism for discrete and continuous movements are different.
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Dorsolateral prefrontal cortex activity during the learning of computer tasks in a contextual interference paradigm using fNIRs: A case series Shewokis, Patricia A.; Hasan Ayaz, Kurtulus Izzetoglu, Meltem Izzetoglu, Scott C. Bunce, Maria T. Schultheis, Kambiz Pourrezaei; Drexel University One interpretation of contextual interference is that during acquisition a random practice order involves more cognitive processing than a blocked order because of the number of tasks and task features that are compared in working memory and results in enhanced retention and generalization. The dorsolateral prefrontal cortex (DLPFC) is thought to be involved in the maintenance of items in working memory and response selection (Wood & Grafman, 2003). The purpose of this study was to characterize the neural activity of the DLPFC during the acquisition and learning of computer tasks for blocked and random practice orders. Two righted-handed adults (one male, one female) were randomly assigned to either a blocked or random order. Each performed 35 acquisition trials each of three customized 3-D computer mazes (MazeSuite 1.0; Ayaz, 2005) across three days and 72 hours following acquisition, 30 retention and 20 transfer trials (2 mazes) were performed in a random order. DLPFC activity was monitored during all phases for 16 optode sites using functional near-infrared spectroscopy (fNIRs), an optical imaging technology which measures changes in cortical hemoglobin concentration associated with neural activity. Dependent measures included relative changes in the mean and maximum of oxygenated hemoglobin (oxy-hb) and behavioral measures of time (ms) and path length for the mazes. Random practice resulted in faster and shorter path lengths (9,344 + 925 ms and 37.0 + 0.7; 41,525 + 26,671 ms and 76.2 + 39.2) compared to blocked practice (10,103 + 678 ms and 37.4 + 1.1; 44,952 ms + 21,447 and 91.2 + 37.8) for retention and transfer, respectively. The patterns of mean oxy-hb for blocked and random practice decreased across retention trials indicating reduced activity in the DLPFC. During transfer there were increases in peak oxy-hb across the trials with different peak oxy-hb patterns for each order. Discussion focuses on the roles of cognitive processing and DLPFC metabolic neural activity during learning with different practice orders. Accurate perception of mass judgment: Breakdown factors reexamined Shim, Jaeho; Baylor University; Jeong Eun Lee, Dong Won Yook; Yonsei University The theory of direct perception suggests that observers can accurately judge the mass of a box picked up by a lifter shown in point-light display. Our previous research has shown that accurate perceptual abilities are limited to specific circumstances. The purpose of the present study was to reexamine accurate perception of mass corresponding to varying mass lifted, lifter’s strength, lifting speeds, and action types. In contrast to previous research, viewing manipulations were made from an ideally, and not a poorly judged, condition. We first created a circumstance where observers accurately judged lifts of five box masses performed by a lifter of average strength. In Experiment 1, we added observation of lifts of four additional, heavier masses performed by the same lifter. Thus, the masses ranged from 2.3 to 38.6 kg (which was almost a full range of the lifter’s maximum lifting strength). We also had a stronger lifter perform lifts of box masses which also covered a full range of that lifter’s strength. Fifteen and 14 observers viewed the average-strength and strong lifters, respectively. Results showed that observers viewing the strong lifter underestimated the box mass significantly more than the group viewing the average-strength lifter. In Experiment 2, 9.1-g and 22.7-kg box lifts were played at five (either faster or slower than normal) speeds, and were displayed either as lifter+box or box only. Observer judgment of mass
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was significantly influenced by display speed. Examining CV across the five speeds, results of a 2 × 2 (Mass × Display) ANOVA showed a main effect of display with less variation in the lifter+box condition. In Experiment 3, 20 observers gave estimation of box masses with live action rather than verbal report. Observers significantly overestimated mass when estimating using live action compared to verbal report. In conclusion, observers’ perception of kinetic property is accurate in sequence but inaccurate in true magnitude when viewing lifters of different strength, lifting speeds, and action types. Postural control in individuals with multiple sclerosis: A dual-task approach Shin, Sunghoon; Jean M. Samson, Stefani J. Voudrie, Erin M. Snook, Jacob J. Sosnoff, Robert W. Motl, University of Illinois at Urbana-Champaign Individuals with multiple sclerosis (MS) have deficits in both cognitive function and postural control. Traditionally, it is maintained that deficits in postural control in MS result from neuromuscular dysfunction. However, it is possible that the difficulties in postural control partially result from difficulties with cognitive function. The purpose of this investigation was to examine postural control in individuals with MS and the effect of performing a concurrent cognitive task on postural control. The sample included 11 individuals with MS and 9 age and gender matched controls that completed an upright postural task in isolation and while performing a cognitive task The cognitive task was silently counting backwards by 7 (i.e., serial sevens). Center of pressure excursion in the anterior-posture (AP) and mediallateral (ML) directions, total sway length, and sway area (95% ellipse) were calculated. As expected, individuals with MS had greater sway in the AP and ML direction, total sway length, and sway area than the controls. The addition of a secondary dual task significantly influenced the sway length in the ML direction, but this effect did not differ between MS and controls. There were no interactions between group and dual task on any of the postural control measures. Overall, the findings confirm the effect of MS on postural control and suggest that there is not an increase in the adverse effect of a cognitive task on postural control in individuals with MS. Comparison of center of pressure in inverted and upright stance positions Silver, Tobin A.; J.H. Ryu, J.M. Haddad, S. Rietdyk; Purdue University Fluctuations in the center of pressure signals may exhibit increased flexibility in the exploration of the base of support, consistent with improved balance capabilities. In addition, when these fluctuations’ variability are embedded in a higher dimensional state space throughout a time series, it may improve our understanding of the sensory motor system. This project explored the temporal fluctuations of the center of pressure while performing a difficult static stance and compared the results to a “simple” task. It was hypothesized that a challenging postural task would exhibit a more deterministic mechanism to maintain stability. To date, three healthy college-age females have participated 23 ± 4.6 years. Data collection is continuing. Participants performed two stance conditions: (1) quiet stance, where the participant stood quietly on a force plate, (2) inverted stance, where the participant balanced on their head on a force plate. For all three participants, head standing resulted in larger center of pressure displacement in the medial lateral (19.0 ± 10.1 vs. 1.3 ± 0.8 mm) and anterior posterior directions (10.5±8.1 vs. 5.1 ± 1.4 mm), decreased percent recurrence (3.4 ± 2.1 vs. 7.4 ± 1.1%), and increased percent determinism (99.5 ± 0.5 vs. 98.0 ± 0.8%). Additionally, entropy was larger during the headstand for two of the three participants (6.3 ± 0.5 vs.
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5.8 ± 0.7). These changes are consistent with the subject adopting an oscillatory strategy to control balance in the more challenging task, possibly indicating the balance control system is deliberately causing oscillatory body sway, so that it “knows” where the center of mass is going and where it has been, decreasing the chance of a fall caused by a perturbation. The changes in dependent variables and proposed strategy are similar to observations of balance control in Parkinson’s disease, where the subjects are challenged by neurological changes rather than postural changes. Does minimizing errors during practice result in superior learning for both experienced and inexperienced individuals? Smith, Peter J.; Illinois State University Maxwell, Masters, Kerr, and Weedon (2001) suggested that minimizing errors during practice elicited a more implicit performance style, which resulted in superior learning relative to more errorful practice. They excluded participants from their study if they had any previous experience of the task, on the basis that implicit learning was less likely for those who could draw on previous experience to guide current performance. However, their results indicated that “errorless” learning was effective despite these learners acquiring explicit rules during practice. Given this, the current study examines whether minimizing errors during learning is effective both for inexperienced and moderately experienced performers. Participants (N = 48) had either none, or between 3 and 7 years of informal golfing experience. The design followed that of Maxwell et al. (2001), where all participants practiced 50 golf putts from each of eight distances, but a minimal error group practiced short putts first followed by increasingly longer putts, while a maximal error group practiced the same putts in the reverse order (longer first). Both the number of successful putts and the time taken to address the putt was recorded during practice, and learning was assessed using a retention test, a transfer task requiring participants to count tones while putting, and a transfer task requiring putting across over a 6-inch ridge. Regardless of level of experience, minimal error practice resulted in fewer errors both during practice and retention. In secondary task transfer, only inexperienced individuals in the maximal error condition experienced impaired performance (suggesting less automatic performance). In novel task transfer no differences due to practice order emerged. All participants reported acquiring rules for task performance. On the basis of these findings it is suggested that the benefits of reducing errors during practice is not restricted to those with no task experience, and that such benefits might persist despite the accumulation of explicit knowledge of the task. Effects of bilateral skill training on the acquisition of fast overhand throws: A motor learning study with schoolchildren Stöckel, Tino, University of Leipzig, Matthias Weigelt, Bielefeld University, Jürgen Krug, University of Leipzig In team sports, athletes are frequently confronted with situations in which they have to adapt their skills to fast changes of play, often requiring the flexible execution of a particular movement skill. Little is known, however, about how bilateral practice of such skills can contribute to strengthen the dominant (throwing) hand. The present study investigated contralateral sequence effects on the acquisition of fast overhand throws, a skill used in team handball. Twenty-two school children (mean age = 11.7 years old; ranging from 10 to 14 years old) practiced the overhand throw under one of two training schedules in 8 sessions over 2 weeks:
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(1) the skill was initially practiced with the preferred, right hand for four sessions, before changing to the nonpreferred, left hand for the remaining four sessions (P-NP group), or (2) the skill was initially practiced with the nonpreferred, left hand, before changing to the preferred, right hand (NP-P group). Throwing speed (as a measure of throwing strength) was recorded for the dominant hand before the first training session (pretest), before changing the throwing hand (intermediate test), after the last training session (posttest), and after two weeks without practice (retention test). The analysis of the pretest/intermediate test, the pretest/posttest, and the pretest/retention test differences demonstrated a significant increase in throwing speed for the P-NP group as compared to the NP-P group. This was evidenced by higher throwing speeds with the dominant hand, even after the skill had to be retained over two weeks without practice. These results can be taken as evidence for contralateral sequence effects on the acquisition of a complex movement skill, and for the notion that bilateral training can improve motor performance on the dominant side of the body. Practical implications for the acquisition of skills for a number of team sports are drawn. Fatigue-induced adaptations to anticipatory postural adjustments (APAs) found in non-fatigued muscles: Support for central control of APA adaptation to fatigue Strang, Adam J.; William P. Berg, Miami Universitsy Anticipatory postural adjustments (APAs) refer to muscle activation occurring in the trunk and lower extremity that precede an expected or self-initiated perturbation of the body. Previous studies have shown that APAs undergo fatigue-induced adaptations that include early onset of muscle contraction. Early APA onset has been postulated to reflect a functional adaptation by the CNS to maintain postural stability during a focal movement performed in a fatigued state. It remains unclear, however, whether fatigue-induced early APA onset reflects a central CNS motor command or peripheral response muscle contractile properties or EMG artifact. One way to decipher whether APAs represent a central or peripheral response is to investigate whether fatigue-induced early APA onset can be found in nonfatigued muscles. If fatigue-induced early onset of APAs exist in nonfatigued muscles, then the central mediation of APA adaptations would be supported. In this study the APAs of thirty participants were recorded before and after conditions of either rest (n = 15) or fatigue (n = 15). APAs were induced through a rapid bilateral reaching task and APA onsets were observed using surface electromyography recorded bilaterally from the L4 erector spinae, rectus femoris, and semitendinosus muscles. Postural stability during the bilateral reaching task was recorded using a forceplate. Muscle fatigue was produced in the right leg using an isokinetic knee flexion/extension exercise. Results showed that fatigue-induced early APA onset was identified in the left, F(1, 26) = 9.95 p = .004, and right, F(1, 26) = 4.00, p = .056, L4 erector spinae muscles, despite the fact that neither of these muscles were involved in the exercise. In addition, all measures of postural stability either improved or were unchanged following fatigue. Based on these results, it appears that fatigue-induced early onset of APAs is centrally mediated and that this adaptation reflects a functional attempt by the CNS to maintain postural stability in the presence of fatigue. Synchronization timing is unique for tapping and circle drawing Studenka, Breanna E.; Howard N. Zelaznik, Purdue University Human motor timing can use an internal representation of time event timing or timing can emerge from control of movement. Differences between event and emergent timing have
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been explored for continuation movement without the aid of an external timing signal using repetitive tapping and repetitive circle drawing, respectively, as windows into event and emergent timekeeping processes (Robertson et al., 1999; Spencer et al., 2003; Zelaznik et al., 2005). Many tasks, however, require that an individual entrain to an external signal (e.g., musicians to a conductor and marching soldiers to a drill sergeant). This synchronization behavior has been well studied in tapping. If the external timer produces a shorter or a longer than expected interval, the performer makes a rapid adjustment, called a phase correction (Repp, 2000; 2001). This correction occurs even when the participant is not aware of the perturbed interval. An initial study examined whether phase correction occurred in synchronization circle drawing (Studenka & Zelaznik, NASPSPA 2006). We could not answer the question in that study because subjects were not able to synchronize in circle drawing. In the presently reported study, new procedures were developed to ensure that a subject was synchronized in circle drawing, prior to any potential temporal perturbation. Sixteen subjects performed two tasks, tapping and circle drawing, for 136 trials each. A trial involved five movements to an auditory metronome period of 400 ms, 10 movements without the metronome and, finally, 10 movements synchronized with the metronome. The 4th, 5th, or 6th interval of the last series was shortened or lengthened by either 25 or 100 ms. Subjects were initially synchronized with the metronome, resolving the main roadblock from the previous experiment. A change in the metronome interval elicited minimal error correction in circle drawing compared to the rapid and complete error correction seen in tapping. This new study presents another line of evidence bolstering the distinction between event and emergent timing processes. Use of enhanced feedback for arm motor recovery in chronic stroke survivors Subramanian, Sandeep; Alain Ptito, Mindy F. Levin, McGill University Virtual reality training environments (VEs) are promising new tools to improve functional recovery level in chronic stroke survivors. VE incorporates elements essential to maximize motor learning and recovery such as motivation and task relevant feedback. However, whether arm movement quality is improved by training in a VE that optimizes these elements has not been investigated. This is important since patients present with different levels of cognitive impairments that might affect their ability to use enhanced feedback. The study objectives were to determine whether training in VE leads to greater changes in arm motor patterns (movement quality) compared to similar training in a physical environment (PE) and to estimate whether cognitive impairments affected these changes. Twelve stroke survivors practiced 72 pointing movements in VE or PE for 10 sessions spread over 2 weeks. Both environments had 6 targets arranged in 2 rows in the ipsilateral, central, and contralateral arm workspaces. Clinical evaluations of arm impairment and function were done. Motor patterns used for a pointing task were evaluated (Optotrak, 100 Hz, 6 markers) before and after training and at 2 follow-up points (1 and 3 months). Cognitive function was also tested (memory, attention, mental flexibility, and problem solving). Both groups received feedback about use of motor compensations (knowledge of performance), movement speedm and end-point precision (knowledge of results). After training, the VE group increased shoulder flexion (p < 0.05). Trends were seen towards better performance in the VE in terms of shoulder horizontal adduction, speed, and precision. Patients with fewer deficits in executive functioning performed better in the VE. There was a positive correlation with speed (r = 0.62) and negative correlation with precision (r = −0.61) Training in VEs may offer a motivating and challenging environment for rehabilitation interventions.
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Effect of two types of imagery on throwing accuracy in cricket Thanikkal Kottayil, Soni John; Tony Morris, Victoria University of Technology Imagery is one of the most widely used psychological training methods in teaching and learning of motor skills. Mental imagery is used to signify the mental rehearsal of movement patterns through multi-sensory imagery prior to actual execution. Imagery can be used in sports for a range of functions, including performance enhancement, skill learning, and as a strategy for covert behavior modification. There have been a number of studies that have explained the effectiveness of imagery as a psychological strategy to enhance performance. We conducted a pilot study to examine the effect of two types of imagery on performance of a throwing task and also to test the efficacy of using imagery as a psychological tool with minimum processing time during the course of the movement. The first type of imagery used was traditional, real-time imagery and the second type was a reflective form of imagery with minimum processing time executed during the course of the movement. The reflective imagery represented intrinsic concrete reflections of the immediate task ahead during the approach movement to the task. The participants of the study were 12 male intercollegiate cricketers. We pretested participants for throwing accuracy. Then we randomly divided participants into three groups of four. We gave the first group traditional imagery and the second group the reflective form of imagery. The third group acted as a control group, participating only in the physical training of throwing for accuracy. We trained the participants for 6 weeks. Though the results were not statistically significant, mainly owing to the small number of participants, they provided encouraging signs because the reflective imagery group had larger performance gain scores compared to the traditional imagery group and the control group. The reflective imagery technique showed sufficient promise that further research should be conducted with larger samples, different tasks, and various kinds of participants. Bandwidth feedback in the learning of a volleyball serve Ugrinowitsch, Herbert; Fabiano S. Fonseca, M.F.S.P. Carvalho, Vitor L.S. Profeta, Rodolfo N. Benda; Universidade Federal de Minas Gerais Bandwidth knowledge of results (KR) has been investigated with laboratory motor tasks but rarely with sports motor tasks and consequently with knowledge of performance (KP). Furthermore, the experiments tested different bandwidths with its respective yoked groups and in general, although bandwidth groups had better performance than yoked groups, the results did not show agreement about the best bandwidth to the motor skill acquisition. This study aimed to investigate the effect of different bandwidth KP in the learning of the volleyball tennis serve. Twelve boys from 11 to 13 years old practiced the task that involved performing the tennis serve 4 m away from the net, trying to reach one round 2-m-wide target positioned in the opposite court, 3 m away from the net. The score from each serve was from 1 point (i.e., ball that did not cross the net to the opposite court) to 14 points (i.e., ball that reached the center of the target) and 8 points were selected and divided in three levels to give KP hierarchically during learning phase, which were analyzed later. The experimenter gave feedback about the first wrong point in the hierarchy accordingly to the group and just moved to another point after the volunteer performed the previous one correctly. These points were used to motor pattern qualitative data analysis as well. Three groups (n = 4) were randomly formed: no bandwidth group (NG), thin bandwidth group (TG) and wide bandwidth group (WG). The experiment had a pretest with 10 trials, acquisition phase with 120 trials, and posttest with 10 more trials. The analysis between pre- and posttests showed that although
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there was no score difference among the three groups, the WG had better movement pattern in the first and second points than NG and TG. These results show that wider bandwidth helps the motor pattern learning and thinner bandwidth has similar results to no bandwidth feedback. This research was supported by FAPEMIG, no. ED-419/05. Using 1/f noise to examine planning and control in a discrete aiming task Valdez, Andre B.; Eric L. Amazeen, Arizona State University Skilled movements generally reflect the influences of both a plan that changes slowly from one execution to the next and control processes that produce moment-to-moment changes in the movement. When such slow and fast moving processes operate together, the result can be 1/f noise. In fact, there is recent evidence of 1/f noise, or long-range correlation, in discrete aiming primarily during the initial stage of the movement. The present study used 1/f noise to examine further how movement timing affects planning and control processes in a discrete aiming task. Participants performed aiming movements at their preferred and fastest speeds. Multiple fractal time series analyses were applied to the data to provide converging evidence of 1/f noise: power spectral density, standardized dispersion, rescaled range; and to distinguish between short- and long-range processes, autoregressive fractionally integrated moving average (ARFIMA: comprised of a model selection procedure based on Akaike and Bayes information criteria that involved fitting 18 models to the time series studied). Measures obtained from all four analyses were in reasonable agreement, with a higher percentage of ARFIMA (i.e., long-range) models selected at peak velocity in the preferred speed condition and a comparatively smaller percentage selected at peak velocity in the fast condition. The measure of fractal dimension averaged across spectral density and standardized dispersion suggested an emerging trend that, for movements at preferred speed, of those participants who showed 1/f noise, more showed 1/f noise at peak velocity, when planning and control would overlap through time to the greatest degree. And for fast movements, where planning and control would have less time to overlap, of those participants who showed 1/f noise, fewer showed 1/f noise at peak velocity than in the preferred speed condition. These results provide initial evidence that, with sufficient time for both planning and control, 1/f noise in aiming may arise from a summation of short-range processes. The effect of plantar-surface sensory stimulation on gait in Parkinson’s disease Van Oostveen, Rachel B.; Quincy J. Almeida; Wilfrid Laurier University; Sandi J. Spaulding, Andrew M. Johnson, University of Western Ontario; Stephen D. Perry, Wilfrid Laurier University and Toronto Rehabilitation Institute; Marj E. Jenkins, University of Western Ontario Many spatiotemporal parameters of gait dysfunction have been reported among individuals with Parkinson’s disease (PD), including reduced velocity and step length. Studies have also reported reduced proprioceptive function and decreased plantar-surface touch sensation among individuals with PD, and proposed that these deficits may predict gait impairment. Yet, it is not known if this is due to reduced sensory receptor function, reduced motor output, or an interaction of these factors. The present study evaluates the effect of plantar-surface cutaneous sensory stimulation in a sample of 40 individuals with PD, and 40 healthy, agematched participants. Stimulation was accomplished through the use of a facilitatory shoe insole with a raised ridge around the lateral and posterior aspects of the foot. All participants demonstrated normal plantar sensitivity and were randomly assigned to one of two groups—
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one in which stimulation was provided with the facilitatory insole first followed by a blank insole, and one in which they were provided with the blank insole first and the facilitatory insole subsequently. All participants completed five walking trials with each insole and spatiotemporal gait parameters were assessed using an instrumented walkway. Despite the fact that a number of participants with PD reported a qualitative increase in sense of balance, no significant between-group differences were demonstrated for most gait parameters. Adaptation appears to be evident through a significant Group × Trial interaction, as participants with PD responded differently when initially using the facilitatory insole. Thus, although plantarsurface stimulation is unlikely to produce deleterious effects for individuals with PD, it does not appear to result in immediate large-scale gait improvements either. However, trial data suggests that there may be an underlying sensory effect that requires further examination. Additionally, the anecdotal reports of improved balance (and in one case, reduced freezing), provides good justification for longitudinal assessments in the future. Effects of intervals of KR presentation in motor skills acquisition Vieira, Márcio M.; Herbert Ugrinowitsch, Rodolfo N. Benda; Universidade Federal de Minas Gerais Knowledge of results (KR) is information about difference between the aim of the task and the real action result. An important aspect of KR supplies is the temporal locus, which is the moment that KR is informed. This question involves three intervals: delay KR, post-KR interval, and intertrial interval. This study aimed to investigate these intervals in three experiments using the same task. Ninety subjects performed a positioning task. It was developed using an apparatus that consisted by a wooden box, with six recipients and a key button to start and finalize the task. The closest recipients were named by 4, 5, and 6 and the more distant recipients were named 1, 2, and 3. In acquisition phase, the subject should press the key button waiting the LED lights turn on. After this, the subjects should move three tennis balls from the closest recipients to more distant ones in a sequence 4–2/5–3/6–1 and in time target of 3,000 ms in 30 trials with KR after every trial. After 10 min, the subjects performed, in immediate transfer test, 15 trials in a new task with new sequence (6–1/5–3/4–2) and new target time (4,000 ms) without KR. Another transfer test was realized 24 hours after acquisition phase. The first experiment investigated KR delay with three groups (n = 10): pre-KR, 4 s; pre-KR, 8 s; and pre-KR, 16 s. The results showed best performance of pre-KR 4 s group. The second experiment analyzed post-KR interval with three groups (n = 10): post-KR, 4 s; post-KR, 8 s; and post-KR, 16 s. The results did not show differences among groups. The third experiment investigated intertrial interval with three groups (n = 10): 4 s (pre-KR 2 s and post-KR 2 s); 8 s (pre-KR 4 s and post-KR 4 s); and 16 s (pre-KR 8 s and post-KR 8 s). The results showed that 16 s group had the worst performance. The experiments suggest that KR delay and intertrial interval seems to be more important that post-KR interval. However, new studies must be conducted to investigate whether these results are confirmed in different tasks. Toward an integrated theory of muscular effort–grip force compatibility Wallace, Stephen; David Anderson, Ryan Streeter, Mark Gorelick; San Francisco State University The study of reaching, grasping, and manipulation has become a fundamental paradigm for investigating broader questions about the control of actions and the remarkable dexterity of
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human behavior. Following a review of 4 recent experiments, we build upon an intriguing discovery concerning the errors associated with using the anatomical hand or two types of prosthetic prehensors to regulate grip force. Consistent with impulse-variability theory (Schmidt & Lee, 2005), error and error variability increases when the anatomical hand or a voluntary closing (VC) prehensor apply increasing levels of grip force to an instrumented object, whereas the opposite pattern of errors occurs when a voluntary opening (VO) prehensor is used. These divergent findings have led us to formulate the muscular effort–grip force compatibility (MEGFC) hypothesis. In the current presentation, we elaborate upon the MEGFC hypothesis by presenting new predictions related to muscle selection, attention demands, and required speed of response, along with specific experiments to test those predictions. We argue that the VO terminal device, as well as other tools that share its mechanics, while useful for holding objects, may be less than desirable in those tasks requiring grip force modulation. An important future direction concerns the generalizability of the findings with the VO and VC prehensor. Currently, there are several VO-like tools in the marketplace that are used in contexts as diverse as eating escargot and performing delicate surgeries. Do these tools suffer the same limitations as the VO prehensor owing to MEGF incompatibility and, if so, in what tasks and contexts are the limitations most apparent or serious? It is also possible that VO-like tools will have unsuspected advantages relative to VC-like tools, such as when high forces must be applied to an object and a low variability of force output is required. Understanding the limitations and advantages of VC- and VO-like devices could lead to the design of much more effective tools for object manipulation. Arm to leg coordination in butterfly stroke Wang, Ning; Yeou Teh Liu, National Taiwan Normal University Butterfly stroke is a unique swimming style. The simultaneous arms movement during the recovery period above the water earns its name of “butterfly.” Butterfly stroke has been considered as the most difficult swimming style to perform because of the synchronizing characteristics of the arm and leg movements. However, the forward speed not only depends on the arms and the legs movements, but also relies heavily on the arm-leg coordination. The aim of this study was to examine the difference of the arm-leg coordination patterns in the butterfly stroke between two levels of swimmers who were specialized in butterfly stroke at three race paces (50 m, 100 m, and 200 m). Eight Taiwanese elite swimmers and eight Division B college swimmers participated in the study. Two underwater high-speed cameras (200 Hz) were synchronized to capture the swimming movement. The kinematics data were digitized and calculated with the Kwon 3-D software. The shoulder and knee joint angles were used to derive the continuous relative phase and the timing difference between the arms’ entry to water and the occurrence of the first minimum knees angle was used for the discrete relative phase. The results showed that although both levels of swimmers demonstrated a 1 to 2 ratio between the arms and the legs movement, elite swimmers had a more consistent relative phase among different pace and among different stages of the cycle. For the discrete relative phase, the difference between performance levels was only found significant at the lowest pace. In conclusion, the continuous relative phase may be used to characterize the general coordination pattern of butterfly stroke whereas more specific synchronization between arms and legs may indicate different skill levels. More on neural processing during action observation and action execution in Down syndrome
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Weeks, Daniel; Simon Fraser University; Naznin Virgi-Babul, Alexander Moiseev, Teresa Cheung, Down Syndrome Research Foundation; Douglas Cheyne, Hospital for Sick Children According to the direct matching hypothesis, actions that are performed by others elicit activation of the same neural substrates involved in the execution of the observed action, suggesting a common coding between perception and action. This hypothesis has found support from the recent discovery of “mirror neurons” (Rizzolatti et al., 1996). There is well-documented evidence that persons with Down syndrome (DS) have difficulties associated with motor learning and skill acquisition. To investigate whether an action observation/ action execution matching system is preserved in individuals with DS, we compared neural responses during action observation and action execution in adults with and without DS using magnetoencephalography (MEG). Participants were asked to make self-paced reach-to-grasp movements (execution), or view the same movement made by the experimenter (observation). Cortical responses were recorded with a 151-channel whole-head MEG. Signals were first analyzed by computing the power spectra from fast Fourier transformation on single trials. Modulation in the µ, 8–10 Hz frequency band was examined because action execution and observation have been found to reduce the magnitude of the µ rhythm (Pineda, 2005; Lepage and Theoret, 2006). A SAM beam former was used to the highest evoked signalto-noise ratio in the .2- to 50-Hz band. Time frequency plots of cortical activity were then calculated. In all participants, execution of action resulted in µ suppression. As would be expected, observation of motion resulted in left hemisphere µ suppression in participants without DS over the left premotor and parietal areas. In contrast, there was minimal to no left hemisphere beta desynchronization in the participants with DS during the observation condition. Paradoxically, we observed a reversal in the pattern of µ suppression in the DS group, suggesting a right hemisphere mirror neuron response. It may be that at least some of the skill performance and acquisition challenges associated with DS are related to atypical perceptual-motor coupling. Dynamical information and deception in tennis Williams, Andrew M.; Liverpool John Moores University; Raoul Huys, University of the Mediterranean; Rouwen Canal-Bruland, Norbert Hagemann; University of Muenster Although there has been a significant growth in research examining issues related to anticipation skill in sport, there have been few published reports focusing on the mechanisms underpinning deception. The ability to effectively deceive an opponent as to one’s likely intentions would appear to be an important component of performance, particularly at the very highest levels of competition (Williams & Ward, 2007). We employed a novel approach to examine deception effects in tennis by manipulating the dynamical information presented at different body regions + racket. Three-dimensional data from six skilled tennis players executing inside-out and cross-court shots to different areas of the court served as stimulus material. We interchanged the dynamics at selected regions with those from strokes played to the opposite side of the court in an effort to induce false beliefs in relation to opponents’ intentions. Skilled (n = 12) and less skilled (n = 12) tennis players were required to anticipate stroke direction when presented with filmed sequences in stick-figure format in all 96 trials. There was a significant Skill × Condition interaction. Skilled players reported lower accuracy scores when both proximal (i.e., shoulders, trunk, and legs) and distal (i.e., arm + racket) cues were interchanged, implying use of a global perceptual strategy. The less skilled players showed a significant decrement only in the arm + racket condition, suggesting a more
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localized search process. Performance accuracy scores for both groups were only significantly below chance in the arm + racket condition, highlighting the importance of end-effector information when perceiving opponents’ intentions. Findings have implications for perceptual training and sportswear manufacturers interested in eliciting deception effects. Enhancement consolidation for a simple procedural task: Influence of increasing practice Wright, David L.; Joohyun Rhee, Amber Vaculin; Texas A&M University Within- and between-session phases of skill acquisition are accompanied by an intermediate phase, occurring within hours of the completion of training, manifest as robust offline performance gains beyond those expected from more practice. Offline gains, from memory consolidation, are reliably greater after sleep and conversely can be ameliorated with practice of a related task within less than 6 hr of initial training. The present study addressed whether increasing the extent of practice of a procedural task led to (a) an increase in the magnitude of the offline improvements, and/or (b) a reduction in the influence of practice with an interfering task for offline gains. Speed, number of correct sequences per trial, and error, percentage of erroneous key presses per trial, were recorded for each 30-s trial of a five-key sequence, A. Individuals experienced either 12 (short practice) or 48 (long practice) trials of practice of A. Half of the individuals in the short and long practice conditions experienced 12 additional trials with an alternative five-key sequence, B, 2 hr after the completion of practice of A. All participants returned 24 hr after the practice of A to complete three test trials for A. As expected, similar significant improvements in speed and error were evident for the first 12 practice trials of A for all practice conditions. A further reliable increase in speed and reduction in error for A was observed following longer practice. Predicted speed and error for the test trials was based on a logarithmic regression for each individual’s practice trials. Offline gain was defined as performance superior to the predicted speed or error. Reliable offline gains in speed were observed following short but not long practice. Exposing the learner to considerably greater practice within one session ameliorated the emergence of offline gains. Interestingly, incongruent with previous reports, exposure to a distracter sequence in close temporal proximity to the training of A had no influence on the display of offline gains. An external focus of attention increases jump height Wulf, Gabriele; Janet S. Dufek, Carolina Granados, Christina Pettigrew; University of Nevada, Las Vegas The present study followed up on a previous study showing that individuals jumped higher when they adopted an external focus of attention, relative to an internal focus or a control condition (Wulf, Zachry, Granados, & Dufek, 2007). The current study was aimed at determining the underlying causes of this effect. Participants performed a maximum-height vertical jump-and-reach task, using a Vertec measurement device. They performed under two conditions in a within-participant design: External focus (i.e., focus on the rungs of the Vertec that were to be touched) and internal focus (i.e., focus on the finger with which the rungs were to be touched). The results replicated those of the previous study, showing that jump height and center-of-mass displacement were greater with an external compared to an internal focus. In addition, impulse as well as joint moments about the ankle, knee, and hip joints were found to be increased in the external focus condition. These results suggest
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that participants jumped higher by producing greater forces when they adopted an external focus. This finding adds to accumulating evidence indicating that focusing on the movement effect (external focus), relative to the movements themselves (internal focus), facilitates the production of effective and efficient movement patterns. Motivational influences on motor learning: The impact of social-comparative feedback Wulf, Gabriele; University of Nevada, Las Vegas; Rebecca Lewthwaite, Rancho Los Amigos National Rehabilitation Center Motivational properties of augmented feedback have long been acknowledged, infrequently studied, and often assumed to produce only temporary effects on movement skill acquisition. The present study examined motivational effects induced through social-comparative feedback on the learning of a balance task (stabilometer). We investigated the influence of normative feedback, delivered in addition to veridical personal performance information (deviation from the horizontal position or root mean square error, RMSE), on the learning of a balance task. Two groups of novice participants, that did not differ in pre-experimentally assessed movement-related outcome, learning, and ability dispositional motivational orientations, received bogus information following each of 14 90-s balance trials over two days of practice. Feedback about the “average” performance of others was presented as a calculated RMSE that was 20% above (worse group) or 20% below (better group) participants’ own performance. Although participants in both groups improved balance performance over the 3-day experiment, the better group significantly outperformed the worse group on both days of practice and through a no-feedback retention test of learning on the third day. A post-experimental questionnaire revealed that participants assessed their own ability on this task in accord with the normative feedback received. Thus, this motivational intervention— potentially operating through feedback impacts on perceived ability—produced learning effects. The role of motivational aspects of augmented feedback on motor skill learning deserves renewed attention in this social-cognitive era. An analysis of KR frequency on the acquisition and retention of a simple movement Wyatt, William R.; Tom E. Parry, John B. Shea; Indiana University Relative frequency of KR has been a central topic in the motor learning literature. Numerous studies have demonstrated the benefits of a reduced relative frequency of KR schedule in learning motor skills (Montare, 1985; Salmoni et al., 1984). Much of the research has compared 100% relative frequency and one other lower relative frequency, commonly 50% (Goodwin et al., 2001) and 33% (Ho & Shea, 1978). However, no single study has completed a holistic appraisal of different relative frequencies and their influence on the acquisition and retention of a simple motor skill. The purpose of this experiment was to investigate the role of relative frequency of KR in the acquisition and retention of a time estimation task. More specifically, how normalized error during acquisition and retention is affected as relative frequency of KR is reduced, and how the learning profile is altered as a function of KR schedule. Subjects were asked to complete a three-key button-pressing sequence in a target time of 1,350 ms. Subjects performed a total of 48 acquisition trials, followed by a 6-min filled retention interval, then 12 no-KR retention trials. During acquisition subjects were assigned to one of eight relative frequencies (100%, 66%, 50%, 33%, 25%, 16%, 12.5%, and 0%). A kernel regression analysis found significant differences in error between
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feedback frequencies during acquisition, F(1, 334) = 25.369, p < .001. The 0% feedback group showed no sign of improvement (slope = .528), whereas the 66% feedback group showed an exponential pattern of improvement reaching near peak performance by trial 33, with a linear slope component of −132.46. A Kruskal–Wallis analysis showed significant differences for error by frequency during the retention period, χ2 = 46.61, p < .001. The 66% feedback group had lower error during retention; however, no linear pattern was found for error by frequency. This suggests that during a time estimation task learning has a pseudolinear relationship with feedback frequency; however, retention does not. The effects of learning cues while teaching the forehand to children with ADHD Yamaguchi, Andrea Y. S.; Iverson Ladewig, Universidade Federal do Parana; Priscila M. Caçola, Texas A&M University A key component of the learning process is selective attention. Depending on children’s age, they may have difficulties ignoring irrelevant information because they have not developed the control processes of selective attention. Discarding irrelevant information may be even more difficult for children with ADHD. Therefore, the objective of this study was to verify the efficiency of learning cues while teaching children with behavioral characteristics of ADHD. Forty-five children of both genders between the ages of 7 and 11 years, with and without behavioral characteristics of ADHD, participated in this study, selected based on the DSM-IV test. Children were distributed into four groups: ADHD-C (ADHD with cues / n = 9), ADHD-NC (ADHD without cues / n = 9), WADHD-C (without ADHD with cues / n = 12), WADHD-NC (without ADHD without cues / n = 15). Every child participated in six trials performing the tennis forehand, using 50 balls in each trial. During each trial, children were introduced to a new technical factor (grip, visualization, forehand position, racket position, ready position in relation to the body, and ready position in relation to the court). In addition to the instructions, children in the learning cue group received a specific cue for each of those technical factors. The dependent variable (the sum of the scores for the analysis of each technical factor) from the pretest, posttest, and retention was used for the evaluation of learning. The statistical treatment was performed using the nonparametric tests. As expected, the children with ADHD not given cues performed more poorly than the other groups, whereas children without ADHD given cues had the best performance. However, the children with ADHD given cues performed similarly in five technical factors to the children without ADHD given cues. Based on these results, the use of cues assisted children with behavioral characteristics of ADHD in learning, thus demonstrating the efficiency of cues while working with children that have problems with attention. Perceiving the distances of opponent’s lunge (in fencing) Yin-Hua, Chen; Liu Yeou Teh, National Taiwan Normal University The ability of perceiving the distances precisely is essential in combat sport, and fencing is no exception. For successful scoring to occur, to escape from the opponents’ attack (lunge) is equally important as to attack aggressively. According to Newell (1986), complex forms of motor behavior can be viewed as products of self-organization arising from interactions between task, environment, and organism constraints. Based on the tri-angular constraint model of Newell (1986), the purpose of the study was to investigate how fencers respond to opponents of different heights and different approaching velocities. Three opponents of different heights approaching in 3 different velocities (freq. controlled by metronome in 120,
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150, 180 bpm) to 8 participating fencers for them to perceive the distance of the opponent’s lunge. All the trials were captured by a camera (30 Hz) and analyzed with the 3-D motion digitizing system. The results showed that all the perceived distances were overestimated, and significant differences were found in different height, F(2, 28) = 12.44, p < .05, and velocity conditions, F(2, 28) = 41.99, p < .05. Height, F(2, 28) = 74.67, p < .05, and velocity, F(2, 28) = 28.76, p < .05 also had significant effect in normalized absolute errors, and there was a significant interaction between height and velocity, F(4, 28) = 8.98, p < .05. These results revealed that fencers’ depth perception would be influenced by the heights of the opponent and the approaching velocities of the opponent. Furthermore, there was a significant correlation between the approaching velocity of the opponents and the absolute errors of the perceived distance, r = .68, p < .05. The results of the study can applied to the training program of fencing, and future study should further look into the interactive situation of the fencers’ behavior. Anticipation timing as a function of expertise and effector specific training Young, Greg; Jeffrey T. Fairbrother, University of Tennessee-Knoxville Del Rey, Wughalter, & Whitehurst (1982) and Hart (2004) demonstrated that increased sport experience was related to superior anticipation timing (AT) performance, especially at faster task speeds. To date, no studies have investigated whether this relationship is a reflection of superior general anticipation capabilities or sport-specific training. The purpose of this study was to test AT performance in experts and novices across preferred and nonpreferred limbs. Expert performers were members of an intercollegiate soccer team. Novice performers had no formal training in soccer and limited experience in interceptive game settings. Participants were required to perform a simple movement task replicating the reception of a pass in soccer by intercepting the apparent motion of a series of lights on a Bassin anticipation timer (Lafayette Instruments) using the preferred and nonpreferred hands and feet. Participants completed 60 trials total at three different speeds: 4 mph, 5 mph, and 6 mph. Dependent variables were constant error (CE) and variable error (VE). For CE, a Condition × Speed interaction (p = .032) indicated that novices were less accurate on the 6-mph task than on the 4-mph and 5-mph tasks whereas experts performed similarly on all the speeds. For VE, a Condition × Preference interaction (p = .047) indicated that preferred limb responses of experts were more consistent than those of novices. These findings suggest that soccer-specific training rather than general anticipation capabilities enabled the experts to respond more accurately and more consistently than the novices. The index finger as the controlled variable in the reaching component of prehension Zaal, Frank; Ingeborg Jol; University of Groningen Prehension is the act of coordinated reaching and grasping. Whereas previous studies have agreed that the distance between thumb and index finger in a precision grip can be used to study the grasping component, the controlled variable of the reaching component has been less clear; most studies have considered the position of the wrist to study the reaching component, others have opted for the position of the thumb, and also other choices have been made. We set out to identify the anatomical landmark that represents the reaching component of prehension. We applied the method of the “uncontrolled manifold” (UCM). The UCM method determines how much of the variability in joint angles in the arm and hand, in this case of prehension, leads to stabilizing the position of—i.e., “controlling”—a
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certain anatomical part. We considered the thumb, index finger, and wrist as potential controlled variables. Preliminary analyses indicated that initially the wrist is being controlled, but that during the largest and final part of the movement it is the index finger that is being kept most stable.
Journal of Sport & Exercise Psychology, 2008, 30(Suppl.), S146-S215 © 2008 Human Kinetics, Inc.
Sport and Exercise Psychology* Perceptions of coaches’ social environment: Supporting or thwarting women coaches’ psychological needs? Allen, Justine B.; Sally Shaw, University of Otago Coaches have been the focus of considerable research, including examinations of coach behavior, athlete relationships (Jowett & Lavallee, 2007) and coach development (Erickson, Cote, & Fraser-Thomas, 2007), typically with the aim of enhancing the quality of athletes’ experience. However, researchers have also argued that coaches should be viewed as performers (Gould, Greenleaf, Guinan, & Chung, 2002) and coaches’ psychological needs be considered (Giges, Petitpas, & Vernacchia, 2004). Furthermore, sport organizations’ practices and culture influence coaches’ experiences and effectiveness (Gould et al., 2002; West, Green, Brackenridge, & Woodward, 2001). Self-determination theory (Deci & Ryan, 2002) has been employed to examine the characteristics of the social environment that support or thwart need satisfaction among athletes (Mageau & Vallerand, 2003) but not for coaches. In addition, there is concern over the under-representation of women in coaching, particularly in high performance sport (Lyle, 2002; Kilty, 2006). Therefore, the purpose of this research was to examine women coaches’ perceptions of their sport organizations’ social environment, with specific attention to psychological need support. Eight regional high performance women coaches from two sports participated in semistructured interviews. Coaches reported considerable autonomy in their activities; however, for some coaches this was experienced as isolating. All coaches reported opportunities to develop their competence through formal coach education; however, they also expressed a desire for more “informal” learning opportunities. A strong connection with their organization and other coaches was considered important; however, the coaches felt that this was challenging owing to existing informal social networks and competition with other coaches for positions. The findings provide insight into the motivational climate women coaches operate within, which should prove useful to those working with coaches, whether as coach educators, administrators, or sport psychology practitioners. Women exercisers’ affective reactions to gender variations in class leaders and co-exercisers Amirthavasar, Gaya; Steven R. Bray, McMaster University A recent study by Kruisselbrink et al. (2004) found that young women reported higher levels of social physique anxiety (SPA) when imagining taking part in mixed-sex exercise groups compared to all-female groups. Exercise class instructors have also been shown to affect exercisers’ psychological states (Bray et al., 2005). The purpose of this study was to investigate women’s ratings of SPA in response to four different exercise environments:
*The abstracts are alphabetically arranged by the first author’s surname within each of the four sections—Interdisciplinary, Motor Development, Motor Learning and Control, and Sport and Exercise Psychology. S146
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female instructor/all-female co-exercisers, female instructor/mixed-sex co-exercisers, male instructor/all-female co-exercisers, and male instructor/mixed-sex co-exercisers. A secondary objective was to examine whether ratings of SPA in response to the different exercise scenarios varied depending on participants’ levels of trait self-monitoring (Snyder, 1987). Young women with experience in group exercise classes (N = 90; M age = 23.51 ± 5.86) completed baseline measures of trait SPA and self-monitoring and state SPA after being presented with written descriptions of each of the 4 exercise scenarios (in random order). Results showed that women expected to feel more anxious about their physiques when exercising with men in the environment. Effects were stronger when the men present were imagined as co-exercisers, with the strongest effects observed when there was male instructor along with mixed-gender co-exercisers, paired t(91) range = 2.17–3.09, p < .05). Contrary to hypotheses, women who were lower in trait self-monitoring showed significant variations in their SPA ratings across the scenarios, paired t(57) range = 2.05–4.06, p < .05), whereas there were no differences (p > .10) across the 4 exercise situations for those who were high in trait self-monitoring. Low self-monitors may be more affected by changes in the exercise setting whereas high self-monitors may be accustomed to regulating their environment. Since SPA has been found to be negatively associated with exercise adherence (Martin Ginis et al., 2007), it may be important to take these factors into account when designing exercise programs for young women. Predicting changes in volleyball players’ well-being from changes in need satisfaction over the course of a competitive season Amorose, Anthony J.; Jillian Cooper, Illinois State University; Dawn Anderson-Butcher, Ohio State University According to basic needs theory (BNT; Ryan & Deci, 2002), the extent to which the psychological needs for competence, autonomy, and relatedness are satisfied will influence one’s physical and psychological well-being. While recent studies in the sport context have provided support for these relationships (e.g., Gagné et al., 2003; Reinboth & Duda, 2006; Reinboth et al., 2004), many questions remain. The goal of this study was to extend the literature by exploring the relationships among need satisfaction and indices of well-being over time. Specifically, we tested whether changes in perceived competence, autonomy, and relatedness over the course of a season were predictive of changes in self-esteem and burnout. Female club volleyball players (N = 93, M age = 15.78 ± 1.28 years) completed valid and reliable questionnaires at both the beginning and end of their season. Paired t tests indicated no significant (p > .05) changes over the season in any of the needs or indices of well-being; however, there was considerable intraindividual variability in the changes that occurred in perceived competence (M change = −.21 ± 1.44), autonomy (M change = −.03 ± .94), relatedness (M change = .05 ± 1.76), burnout (M change = .10 ± .92), and self-esteem (M change = −.00 ± .62). A series of hierarchical regression analyses tested whether changes in need satisfaction over the season predicted changes in each of the well-being variables after statistically controlling for scores at the beginning of the season. As expected, perceived competence (β = −.21), autonomy (β = −.36), and relatedness (β = −.23) significantly predicted changes in burnout (total R2 = .38, p < .01) after controlling for preseason scores on the set of variables. Changes in self-esteem were also predicted by changes in the needs after controlling for the preseason scores (total R2 = .41, p < .01); with perceived competence (β = .50), autonomy (β = .28), but not relatedness (β = −.01) significantly contributing to the relationship. Results are discussed in relation to BNT and implications for creating a positive sporting environment are provided.
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Examining the combined role of individual and environmental factors on leisure-time physical activity behavior in people with spinal cord injury Arbour, Kelly P.; Kathleen A. Martin Ginis, McMaster University The purpose of the present study was to determine whether neighborhood environmental perceptions can enhance the theory of planned behavior’s (TPB; Ajzen, 1985) ability to explain leisure-time physical activity (LTPA) intentions and behavior in people living with SCI. Baseline cross-sectional data from 246 men and women (M age = 44.18 ± 12.17) with an SCI were used to test the study hypotheses. Measures of the TPB constructs, perceptions of the neighborhood aesthetics and wheeling infrastructure, and LTPA behavior were administered over the phone by a trained research assistant. Structural equation modeling was used to test the hypotheses. In partial support of our first hypothesis, subjective norms and self-efficacy were significant predictors of LTPA intentions (β’s = 0.53 and 0.28, respectively). Together, the TPB constructs explained a significant 59% of the variance in LTPA intentions. In partial support of our second hypothesis, intentions emerged as a significant, positive predictor of LTPA behavior (β = 0.21). However, neither of the two PBC constructs (i.e., self-efficacy and perceived controllability) was found to be a significant predictor of LTPA behavior. Overall, the TPB constructs accounted for 10% of the variance in LTPA behavior. Contrary to hypothesis, neighborhood aesthetics and wheeling infrastructure were not found to explain a significant amount of additional variance in either LTPA intentions (ΔR2 = 2%) or LTPA behavior (ΔR2 = 1%). Of interest, though, was the significant, negative relationship between wheeling infrastructure and LTPA intentions (β = −.13, p < .05). Overall, results from the present study suggest that perceived neighborhood aesthetics and wheeling infrastructure do not enhance the TPB’s predictability of LTPA intentions and behavior in people with SCI. Further investigation is needed to determine specific environmental barriers that influence LTPA intentions and behavior in people with SCI. Determining the anxiolytic effects of an acute exercise bout on high anxious individuals using the dot probe protocol Barnes, Robert T.; Steve A. Coombes, Nicole A. Armstrong, Christopher M. Janelle; University of Florida Approximately 40 million individuals suffer from anxiety disorders. The anxiolytic effects of exercise are well documented and are substantiated by a large body of literature that advocates exercise as a successful intervention for reducing anxiety levels and increasing positive affect. Although researchers agree that exercise is an effective tool to alleviate anxiety, questions concerning the mechanisms driving these anxiolytic effects remain unanswered. The purpose of the current experiment, therefore, was to measure the anxiolytic effects of aerobic exercise by investigating pre- and postexercise levels of attentional allocation that are known to generate and perpetuate anxiety. High trait anxious participants (N = 30) completed exercise and quiet rest protocols on separate visits. During the exercise condition, participants engaged in 30 min of exercise on a cycle ergometer at 70% of their HRR, whereas the quiet rest condition consisted of 30 min of solitary rest. During each intervention, pretest and posttest dot probe assessments were completed. Dot probe testing consisted of 48 counterbalanced trials with probes being presented for 500 ms. Reaction times (RT) to emotional stimulus pairs (pleasant or unpleasant images paired with neutral alternatives) were calculated, and a series of self-report anxiety and affective questionnaires (STAI and PANAS state assessments) were administered. As hypothesized, RT was significantly
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faster following exercise compared to the pre- and post-rest conditions and the pre-exercise condition. Contrary to expectations, however, the reduction in RT was ubiquitous across all stimulus pairs, suggesting that attentional allocation was broadly facilitated following exercise. Analyses of self-report data confirmed that positive affect increased significantly, whereas negative affect and state anxiety decreased after exercise. Implications concerning the relevance of these findings to existing psychological interventions will be presented, and future directions will be offered. The relationship between physical activity, functional independence, and depression in individuals with spinal cord injury Barr, Neil; Kelly P. Arbour, Kathleen A. Martin Ginis; McMaster University Participation in physical activity has been associated with a reduction in depression (e.g., Craft & Landers, 1998). Given that individuals with spinal cord injury (SCI) have higher levels of clinical depression (30%) than the general population (5%), physical activity participation may be particularly valuable for this population (North, 1999). Some research has shown that individuals with SCI who exercise exhibit significant increases in measures of functional independence (Duran et al., 2001). Given that trouble in performing daily role functioning (Bombardier et al., 2004) and lower levels of functional independence (Kennedy & Rogers, 2000) have been associated with depression in those with SCI, it was hypothesized that exercise would be related to depression through the mediating influence of functional independence. This possibility was examined in the present cross-sectional study. Study participants were 223 men and women with SCI (M age = 43.66, SD = 12.09). Assessments were completed through telephone-administered questionnaires. Leisure time physical activity (LTPA) was assessed with the Physical Activity Recall Assessment for people with Spinal Cord Injury (PARA-SCI; Martin Ginis et al., 2005). Depression was measured using the Perceived Health Questionnaire (PHQ-9; Spitzer et al., 1999). Functional independence was measured using the telephone motor Functional Independence Measure (FIM; Dijkers & Yavuzer, 1999). Structural equation modeling revealed less than adequate fit indices for the hypothesized model (IFI = 0.86, CFI = 0.85, RMSEA = 0.10). LTPA was associated with increased functional independence (β = 0.17, p = 0.01), and greater functional independence was associated with lower depression (β = −0.18, p = 0.03). Although LTPA was associated with increased functional independence, it was not related to depression (β = 0.02, p = 0.75). Our results suggest that in this cross-sectional study, other unmeasured factors (e.g., social participation, pain) account for more variance in depression than physical activity. It takes more than just a little dissatisfaction: Body image investment moderates the relationship between leisure time physical activity and body image satisfaction Bassett, Rebecca L.; Kathleen A. Martin Ginis, McMaster University There has been mixed evidence regarding the direction of the relationship between leisure time physical activity (LTPA) and body image among individuals with spinal cord injury (SCI), with some studies finding a positive (e.g., Hicks et al., 2003) and others finding a negative relationship (e.g., Heinberg et al., 2001). This suggests that other variables may moderate the relationship between LTPA and body image. For the current study, Cash’s (2002) model of body image was used to examine the relationship between LTPA and functional body image (i.e., satisfaction with physical function) in men living with SCI. Specifically, we explored the moderating role of body image investment (i.e., the effect of
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functional body image on quality of life [QOL]). Men with SCI (N = 50, 50% paraplegic) reported their functional body image (Adult Body Satisfaction Questionnaire; Reboussin et al., 2000), body image investment (Cash, 2002), and completed a 3-day recall of their LTPA (Martin Ginis et al., 2004). Linear regression analysis found LTPA was a significant predictor of functional satisfaction (β = −.27, p < .01). However, the main effects of LTPA were superseded by an interaction with body image investment (β = .43, p < .01). Post hoc analysis showed that among individuals who reported a negative effect of body image on QOL, those who engaged in LTPA were less satisfied with their physical function than those who did not. For those who did not perceive their body image to negatively impact their QOL, there was generally no difference in functional satisfaction between those who engaged in LTPA and those who did not. It has been suggested that body dissatisfaction may motivate some individuals to engage in LTPA (Heinberg et al., 2001). However, for men living with SCI, functional body image may be associated with LTPA only when a negative effect on QOL is perceived. Future research should consider the moderating role of body image investment when examining the relationship between LTPA and body image among people living with SCI. Optimized pre-performance music increases corticospinal excitability Bishop, Daniel T.; Emma Z. Ross, Costas I. Karageorghis; Brunel University Music is used by athletes to optimize pre-performance emotional state, and higher music tempi and volumes can elicit approach-type behavior, which facilitates subsequent choice reaction time (CRT) performance; this may be mediated by activation of neural motor structures. Therefore, the objective of this study was to examine changes in athletes’ motor corticospinal excitability (CE) as a result of listening to purposively selected music. Ten full-time tennis players (8 M, 2 F; M age = 23.0, SD = 4.5 years), participated in each of three conditions (baseline, silence, music) prior to performance of a CRT task, and recorded their affective state. Pulses of magnetic stimulation were subsequently applied transcranially to the motor cortex, and motor evoked potentials (MEPs) in the biceps brachii (BB) were recorded. The participant then responded as quickly as possible to each of 30 randomized CRT trials (10 × 3 alternatives) by striking a corresponding button; EMG data were continuously acquired. Music was rated as significantly more arousing than baseline (p < .01), although ratings were not significantly higher than those for silence. CE was not significantly different across conditions. However, mean stimulation threshold and MEP latency were lower and shorter, respectively, in the music condition when contrasted with both baseline and silence conditions, and average MEP amplitude was higher for music when contrasted with silence. EMG latency in the music condition during CRT performance was significantly shorter than for silence and baseline conditions (p < .05). RTs were not significantly different but, importantly, mean values were again in the predicted direction: 3% and 4% shorter in the music condition than in the silence and baseline conditions respectively. Explanations for the present findings can readily be couched within motivation-based theories of emotion: heightened arousal resulting from emotional responses to music appears to heighten corticospinal activity, the cortical component of which is crucial in determining approachtype behaviors. The role of intentions and planning in relation to current leisure time physical activity levels in first-year undergraduate students Bittner, Jennifer P.; Chelsea Pelletier, Kathleen A. Martin Ginis, McMaster University
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Previous research has demonstrated that there is a significant decline in physical activity behavior during the transition from high school to university (Bray, 2007). This change is of particular importance because it represents a time when young people develop new health habits. Current literature identifies an inconsistency between leisure time physical activity (LTPA; defined as physical activity completed in one’s spare time, structured or nonstructured) intentions and behavior (Sheeran, 2002; Conner & Norman, 2005), termed the intention-behavior gap (Orbell & Sheeran, 1998). Gollwitzer (1993) identified the creation of implementation intentions, or planning, as a useful strategy to help people translate their intentions into behavior. The purpose of the current study was to explore the contribution of planning to the intention-LTPA relationship as described in the health action process approach (HAPA; Schwarzer, 2004). First-year undergraduate students (N = 98) completed assessments of current LTPA levels (mild, moderate, and strenuous intensity), intentions, and planning for LTPA. The planning variable measured the extent to which participants planed when, where, what, and how they would participate in LTPA. A significant correlation was noted between intentions and planning (r = .51, p < .001), and between planning and strenuous LTPA (r = .45, p < .001). However, hierarchical regression analyses revealed that planning did not explain any additional variance in LTPA behavior beyond intentions (R2 adj. = .50), providing evidence contrary to the HAPA. However, this may suggest that the lack of planning for LTPA plays a significant role in the lack of strenuous LTPA behavior in the undergraduate population. Body representation, body activity, and the use of (phantom) body parts Blaesing, Bettina E.; Thomas Schack, University of Bielefeld; Peter Brugger, University Hospital Zurich Body schema has been described as a multimodal representation of the body that integrates somatosenstory, proprioceptive, and vestibular information as well as visual information from observing body dynamics (Funk, Shiffrar, & Brugger, 2005). We investigated mental representations of body parts in two participants with congenitally absent limbs, one of which (Participant A) has perceived phantoms of all four limbs since birth (Brugger et al., 2000) whereas the other (Participant B) has never experienced any phantoms (Funk et al., 2005). Additionally, we tested a control group (group C, N = 12, age: 46.2 ± 9.8) matched to A and B in age and occupation and a group of sport students (group D, N = 18, age: 24.2 ± 2.4). The SDA-M method (Structure Dimensional Analysis–Motorics; Schack 2004) used here has been applied successfully to evaluate cognitive structures of sports movements in the long-term memory of athletes (Schack & Mechsner, 2006). Verbal labels indicating body parts (e.g., thumb, eye, knee) and body-related activities (e.g., writing, walking) were presented to the participants in randomized lists that had to be sorted according to a hierarchical splitting paradigm. Participants were instructed to refer to their somatosensory perception of their own body rather than to an outside image. Results of the hierarchical cluster analysis revealed similar cognitive structures of Groups C and D. The representation structure of Participant A resembles the structures of Groups C and D to a higher degree than does the structure of Participant B. Although the clustering solutions of A, C, and D show a differentiation of upper and lower body, the results of B reflect his specific way of using his foot for writing and gesturing. Results show that different modes of activity and use of body parts strongly influence the representation of one’s own body, and that this also applies to phantoms of limbs never physically experienced.
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Individual versus group-level effects of barrier and task self-efficacy on physical activity Blanchard, Chris M.; Dalhousie University; Eric Nehl, Emory University; Ryan Rhodes, University of Victoria; Frank Baker, New York Medical College Background: To date, the vast majority of research examining the influence of varying types of self-efficacy on physical activity (PA) have relied on group level, i.e., aggregated weighting in the analyses. However, social cognitive theory would suggest that individual efficacy judgments also be considered. Fortunately, having hierarchical data (e.g., individual efficacy judgments) nested within work-related divisions allows one to examine individual and group-level effects of self-efficacy on PA levels. Purpose: To examine the individual and group-level associations of task and barrier self-efficacy with PA. Method: A total of 1,941 employees (mean age = 40.25; SD = 11.41) throughout 17 divisions across the United States completed a Web-based survey that included questions pertaining to demographics, task and barrier self-efficacy, and PA. Results: Hierarchical linear modeling analyses showed that PA was significantly predicted by task (β = .15) and barrier (β = .51) self-efficacy at the individual level and task (β = .10) and barrier (β = .07) self-efficacy at the group, i.e., division level controlling for age, gender, education, race, and marital status. Conclusions: Self-efficacy interventions aimed at changing PA should potentially focus on individual and group-level approaches, particularly for task self-efficacy. The role of barrier self-efficacy and outcome expectations in explaining physical activity in people living with multiple sclerosis Blanchard, Chris M.; Dalhousie University; Nicole Dunlop, University of Ottawa The importance of physical activity (PA) to people living with multiple sclerosis (MS) has emerged in recent years, yet few people with MS engage in enough PA to reap the benefits. The purpose of the present study was to determine whether barrier self-efficacy and outcome expectations could help explain PA levels in people living with MS. Seventy-six participants with MS (mean age = 50.58; SD = 10.38) completed a baseline questionnaire and the Godin Leisure Time Exercise questionnaire via the phone one month later. Mean levels were 44.06 (SD = 25.49) for barrier self-efficacy, 5.87 (SD = 1.12) for outcome expectations, and 35.13 METS (SD = 28.36) for PA. Multiple regression analyses showed that 29% of the variance in one-month PA was accounted for by barrier self-efficacy (β = .34, p < .001) and outcome expectations (β = .27, p < .001) after controlling for functional limitations and education. The present study’s results suggest that developing strategies for people living with MS to increase confidence in overcoming PA barriers and providing knowledge pertaining to the positive outcomes associated with PA may help to increase their physical activity levels. Short-term effects of acute exercise on cognitive functions Blum, Brittany L.; Bruce D. Hale, Joanna K. Garner; Pennsylvania State University Berks In healthy adults, previous research has noted a beneficial effect on Stroop performance after twenty minutes of physical activity (Sibley et al., 2006). Acute exercise has also been shown to positively influence verbal fluency in older, diseased adults (Emery et al., 2001). The purpose of this study was to determine the effect of an acute bout of physical activity on these two aspects of cognitive function in healthy adults, using a true experimental design. Twenty participants were given the Color Word Interference (CWI) and Verbal Fluency (VF)
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scales of the Delis-Kaplin Executive Function System before and after twenty minutes of walking (exercise group) or reading (control group). Eight 2 ×2 (Group × Trials) repeated measures ANOVAs were calculated on the four subtasks of the two scales. Three significant, univariate interactions (VF Category, CWI Naming, Color Word Reading) favored exercisers. The results are discussed in terms of arousal effects on cognitive information processing efficiency. Social and achievement goal orientations, moral disengagement, and antisocial behavior in soccer Boardley, Ian D.; Maria Kavussanu, University of Birmingham Previous research has shown that achievement and social goal orientations predict engagement in antisocial behavior directed toward opponents in sport (Sage & Kavussanu, 2007). The current research extended this work by examining antisocial behaviors toward opponents and teammates, investigating the goal of toughness social status, and investigating whether moral disengagement mediates the relationship between goal orientations and antisocial conduct. Participants were 307 male soccer players (M age = 21.35 years, SD = 4.17), who completed questionnaires measuring task and ego orientations; the goals of social affiliation, social recognition, popularity social status, and toughness social status; antisocial behavior; and demographics. Popularity social status pertains to a player’s desire to be seen as popular within the team, whereas toughness social status refers to gaining respect from teammates by dominating and being aggressive toward opponents. Regression analyses revealed that antisocial behavior toward opponents was predicted by the social goals of toughness social status (β = .19), popularity social status (β = .27), social recognition (β = .13), and social affiliation (β = –.16) and by the achievement goals of task (β = –.26) and ego (β = .45) orientation. Antisocial behavior toward teammates was predicted by the social goals of toughness (β = .20) and popularity (β = .19) social status and the achievement goals of task (β = –.14) and ego (β = .26) orientation. Moral disengagement partially mediated the effects of ego goal orientation and all social goals except for social affiliation on both types of antisocial behavior. Overall, these results aid our comprehension of the motivations that drive antisocial conduct in soccer and suggest that moral disengagement may be an important variable in these relationships. Contextual influences on antisocial and prosocial behavior: Does moral disengagement mediate their relationship? Boardley, Ian D.; Maria Kavussanu, University of Birmingham Past research has demonstrated the importance of the social context in understanding antisocial and prosocial conduct in sport. This study aimed to extend previous work by examining whether moral disengagement mediated the relationships between two aspects of the team environment and four types of antisocial and prosocial behavior in sport. The two aspects of the environment were athletes’ perceptions of their coach’s character-building competency and their perceptions of a mastery motivational climate, while the four behavior types were prosocial and antisocial behavior toward teammates and opponents. Athletes participating in the sports of field hockey (n = 200) and netball (n = 179) completed questionnaires assessing moral disengagement, perceptions of their coach’s character-building competency, perceptions of a mastery team motivational climate, and frequency of engagement in the four types of behavior. Structural equation modeling indicated that perceptions of coach’s
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character-building competency predicted moral disengagement (β = –.31), which in turn predicted prosocial behavior toward opponents (β = –.22) and antisocial behavior toward both teammates (β = .28) and opponents (β = .66). Moral disengagement mediated fully the relationships between perceptions of character-building competency and prosocial and antisocial behavior toward opponents and partially the relationship between these perceptions and antisocial behavior toward teammates. Perceptions of a mastery motivational climate predicted prosocial (β = .49) and antisocial (β = –.42) behavior toward teammates. Multisample analyses demonstrated that the measurement and structural models were largely invariant across the two sports. Overall, these findings assist our understanding of the processes underlying antisocial and prosocial conduct in team sports and may have implications for interventions that aim to eliminate unsportspersonlike conduct. The Moral Disengagement in Sport Scale–Short: Multisample and multilevel confirmatory factor analyses Boardley, Ian D.; Maria Kavussanu, University of Birmingham The Moral Disengagement in Sport Scale (MDSS; Boardley & Kavussanu, 2007) measures the 8 moral disengagement mechanisms proposed by Bandura (1991) and consists of 32 items. The present study aimed to (a) investigate whether a subset of these items could form a short version of the scale; (b) test the measurement invariance of the short scale across gender and sport type; and (c) examine the multilevel factor structure of the short scale. The MDSS was administered to hockey (n = 200) and netball (n = 179) players. Confirmatory factor analysis (CFA) indicated that a model with 3 first-order factors, consisting of 17 items, had a good fit to the data. Based on these results, the Moral Disengagement in Sport Scale–Short (MDSS-S) consists of 17 items and three subscales. The first subscale is termed conduct reconstrual and victim targeting and measures the moral justification, euphemistic labeling, dehumanization, and attribution of blame mechanisms; the second subscale is termed cognitive distortion and measures the advantageous comparison and distortion of consequences mechanisms; and the third subscale is termed nonresponsibility and measures the diffusion and displacement of responsibility mechanisms. The 3-factor structure was confirmed with a second sample of 592 athletes from the sports of soccer (n = 228), rugby (n = 108), netball (n = 130), field hockey (n = 59), and basketball (n = 67). A strong (r = .98) correlation between the total scores of the long and short versions of the scale indicated a high level of convergent validity for the MDSS-S. Multisample CFAs established the measurement invariance of the scale across gender and its partial measurement invariance across the sports of soccer, field hockey, and netball. Finally, multilevel CFA confirmed the factor structure at the within and between-team levels. In conclusion, the MDSS-S is a reliable and valid scale for measuring moral disengagement in sport. Guiding physical activity during transition to university Bray, Steven R.; McMaster University; Mark R. Beauchamp, University of British Columbia; Amy E. Latimer, Queen’s University; Sharleen D. Hoar, University of Lethbridge; Chris A. Shields, Acadia University; Mark W. Bruner, Queen’s University Research has shown a dramatic drop in physical activity (PA) during first year at university compared to the last year of high school (Bray & Born, 2004). In a recent pilot study, Bray et al. (2007) showed that providing first-year students with a specially designed physical activity
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guide resulted in less of a decline in PA during the first semester at university compared to students who received either a general guide (Canada’s Physical Activity Guide; CPAG) or no guide. We extended that study to a broader field trial involving first-year undergraduate students (N = 238) from 4 Canadian universities. A secondary objective was to explore students’ ratings about the student guide in comparison to the CPAG in terms of interest, credibility, and information provision. Students completed measures of physical activity during the second and eighth weeks of their first semester at university and responded to questions about their respective PA guides at the second data collection. Results of a mixed model (Time × Guide Condition) ANOVA showed a main effect for time, demonstrating that average weekly volume of moderate/vigorous intensity PA declined during the first semester at university from pre-university levels, F(1, 231) = 86.10, p < .001. There was also a significant Time × Condition interaction, F(2, 231) = 4.24, p < .05, indicating less decline in PA among students who received the student guide compared to the other two conditions. Those who received the student guide also reported that guide to be more interesting and containing more new information than the CPAG. Both guides were perceived to be highly credible. These findings support previous results indicating first-year students may benefit from the provision of a specially targeted, print-based intervention to encourage moderate and vigorous physical activity during the acute transition to first-year university. The ongoing study will investigate whether these acute effects can persist. Martial art training and philosophy as a moderator of children’s aggression and conduct Brosvic, Gary; Rider University One hundred controls, plus 100 children referred for behavioral issues related to conduct and aggression, participated in an intensive program that alternated 30-day baseline periods (A) with 60-day periods of martial art training (B) according to an ABABABA design. The activities and time spent in the martial arts were balanced between programs that either emphasized a traditional martial philosophy or that presented no philosophical context for training, and, after matching on sex, age, academic performance, prior sport experience, and SES, equal numbers of controls and children with behavior issues were randomly assigned to one of the two martial art programs. Upon completion of the ABABABA design, the participants were followed for 90 days to assess carry-over effects. Multivariate analyses showed significant reductions in the inappropriate behavior of participants referred for behavioral issues when they participated in the martial arts, with the greatest reductions observed for the traditional martial art program centered on a philosophy for using aggression appropriately. Reductions in the inappropriate behavior of participants referred for behavioral issues in the traditional martial art group averaged 73% (median: 58%; range: 35% to 100%) whereas reductions in the nontraditional martial art group averaged 21% (median: 20%; range: 5% to 68%). The magnitude of these reductions continued to be observed during the follow-up period, especially for children who trained on their own or who had joined a martial art style espousing a philosophy for using aggression appropriately. These data support the results of on-going studies in which students with issues related to conduct and aggression who were participating in mixed martial arts (MMA) programs achieved the greatest reductions in behavioral issues when training in MMA programs that espoused a philosophy governing the appropriate and measured use of aggression only during self-defense situations.
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Examining the effects of team building on group task satisfaction in a youth exercise setting Bruner, Mark W.; Kevin S. Spink, University of Saskatchewan Team building (TB) in an activity setting has resulted in higher levels of individual satisfaction (Carron & Spink, 1993). Unfortunately, in that research, satisfaction was only measured at the end of the program so the effects of the TB on the development of satisfaction could not be determined. Further, the study examined individual satisfaction only. Given that satisfaction with the group has been associated with other measures of “groupness” (Spink et al., 2005), one wonders whether the effects of TB could be extended to group satisfaction. The purpose of this study was to examine the effects of TB on the development of group task satisfaction of individuals participating in a physical activity club. Participants included 100 youth (13–17 years) who were participating in 1 of 10 rural, school-based physical activity clubs and completed the program. Participants in five of the clubs were exposed to a 6-week TB program that was adapted from one used previously by Carron & Spink (1993), whereas those in the other five clubs were participants in a 6-week standardized group exercise program. Prior to the intervention, all participants were exposed to a 2-week standardized group exercise program to establish a baseline. To measure satisfaction, a modified measure of group task satisfaction (Reimer & Chelladurai, 1998) was assessed twice—after the baseline and at the end of the intervention. Results from a repeated measures ANOVA revealed a significant Group × Time interaction, F(1, 97) = 11.69, p = .001, wherein perceptions of group task satisfaction did not change over the course of the program for those in the TB program, but it declined significantly for those not exposed to the team-building program. These results extend previous research, which has found a relationship between TB and individual measures of satisfaction (Carron & Spink, 1993), to a measure assessing satisfaction with elements of the group. Further, it appears as if exposure to TB does not enhance satisfaction, but rather helps to maintain it. Supported by CIHR A self-determination theory approach to understanding the relationship between social physique anxiety and physical activity Brunet, Jennifer; Catherine M. Sabiston, McGill University Based on self-determination theory (SDT; Deci & Ryan, 1985) perspectives, this study investigated the relationship between social physique anxiety (SPA) and physical activity behavior. Three hundred and eighty-one older adolescent males (n = 161) and females (n = 220) completed scientifically supported questionnaires. The sample had a mean age of 18.7 (SD = 1.2) years and mean BMI of 22.6 (SD = 3.8) kg/m2. Main data analyses testing the integration of SPA within the self-determination theory were conducted using maximum likelihood structural equation modeling. The theoretically derived model was tested in which SPA was hypothesized to relate to the basic psychological needs, the basic psychological needs were hypothesized to relate to motivation, and motivation was hypothesized to relate to physical activity behavior. Goodness-of-fit statistics revealed good measurement models for the total sample and gender subsamples. Findings of gender invariance suggested that the male and female measurement models were similar. The path models were also deemed good-fitting models and accounted for 46–57% of the variance in physical activity behavior. The paths in the model were not significantly different for adolescent males and females. Collectively, these findings suggest that SPA experiences can be understood within a motivational framework. Further, these results suggest that interventions aimed at decreasing
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SPA among older adolescents may be helpful in promoting physical activity motivation and behavior. The role of active self-regulation and goal progress in promoting the integration of physical activity into the self-concept Carraro, Natasha; Patrick Gaudreau, University of Ottawa A growing body of research indicates that defining oneself as a physically active person relates positively to performance and goal attainment (e.g., Houser-Marko & Sheldon, 2006; Marsh, Trautwein, Lüdtke, & Köller, 2006). However, less is known about the process by which people incorporate physical activity into their self-concept. The aims of the present study were to (a) test whether identification with the physical activity domain would increase the likelihood that people form action plans that could result in greater progress on their goals, and (b) explore whether planning for and successfully progressing on a physical activity goal would increase the extent to which people identify themselves as physically active. The study used a prospective design with 118 university students involved in the pursuit of a self-set physical activity goal. Participants completed measures of identity and action planning at Time 1 and measures of goal progress and identity roughly four weeks later. Results from structural equation modeling with manifest variables indicated that Time 1 identity was positively associated with action planning (β = .47, p < .01) which, in turn, predicted goal progress one month later (β = .40, p < .01). Of even greater interest, it was found that both action planning (β = .13, p < .05) and goal progress (β = .25, p < .01) related to an increase in physical activity identity across time and that goal progress was a significant partial mediator in the planning-identity change relationship. These findings suggest that the use of action planning contributes to a spiraling effect in which the increased likelihood of goal attainment in the physical activity domain is bolstering the integration of this domain within the self-concept. The concrete process of actively working toward a personal goal through the use of planning strategies is thus a means whereby people can obtain success while strengthening important components of their self-concept. These findings have implications for the long-term adoption and maintenance of physical activity behavior. The relationship between perceived coaching behaviors and developmental experiences of high school athletes Carson, Sarah; Daniel Gould, Michigan State University Although sport has the potential to be a valuable psychosocial training ground for youth because of its capacity to instill life lessons and teach life skills (e.g., Hansen et al., 2003), it has been suggested that many variables have to be set in place for the sport experience to promote positive youth development (e.g., National Research Council and Institute of Medicine, 2002). Teams have to be affirming environments, roles and responsibilities have to be clearly stated, and athletes need a supportive leader who coaches beyond basic sport skills. Because of the central role coaches play in promoting youth development, the purpose of this study was to examine how coaching behaviors relate to developmental experiences in high school sports. To address this topic, 297 high school athletes attending 1 of 12 summer sports camps completed Hansen and Larson’s (2005) Youth Experiences Survey–2, the Coaching Behavior Scale for Sport (Cote, et al., 1999), and a set of questions derived from Gould et al.’s (2006) study of life-skill building strategies of successful high school coaches. A canonical correlation analysis revealed, as hypothesized, significant relationships between
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quality of coaching and positive and negative experiences in high school sport. For example, athletes who were more likely to report their coaches exhibited positive behaviors (e.g., helped with mental preparation, talked about how sport lessons relate to life, developed positive rapport with athletes) were also likely to report personal (e.g., initiative) and interpersonal (e.g., teamwork and social skills) developmental experiences through sport. Other findings revealed a correlation between coach–athlete negative rapport and athletes’ negative sport experiences (e.g., stress, negative group dynamics) and a relationship between coaches who emphasized putting team before self and athletes reporting teamwork and social skills developmental experiences in sport. Findings are discussed in light of current research and theory on the positive youth development and sport participation link. Predictive validity of a three-dimensional model of performance anxiety in the context of Chinese tae kwon do sports Cheng, Wen-Nuan K.; Taipei Physical Education College; Lew Hardy, University of Wales, Bangor A three-dimensional model of performance anxiety was proposed to acknowledge the adaptive potential (producing positive effects) of anxiety by including a regulatory dimension (reflected by perceived control) in addition to the traditional intensity-oriented symptoms of cognitive and physiological anxiety. The predictive validity of this model was preliminary examined in the context of elite level of university-based tae kwon do sports performers (N = 99) in Taiwan. Precompetitive anxiety ratings were obtained 30 minutes before performance using a 21-item measure of performance anxiety, previously developed in Chinese according to the proposed conceptual framework. A self-assessed performance measure based on six criteria for optimal tae kwon do performance was administered 30 minutes after competition. Data was analyzed via moderated hierarchical multiple regression. As hypothesized, the component of perceived control accounted for significant additional variance in performance (20.4%) over and above cognitive and physiological anxiety. A significant divergent form of interaction between perceived control and physiological anxiety also emerged, significantly accounting for additional performance variance (11.6%) over and above main effects of anxiety. In total, the whole model explained 36.9% of performance variance. To conclude, this study revealed initial support for the predictions based on the three-dimensional model of performance anxiety. Noteworthily, the regulatory component of perceived control has shown potential in further unfolding the complex relationship of anxiety and sports performance. The influence of team performance on athletes’ self-efficacy and collective efficacy beliefs Chow, Graig M.; Teri J. Hepler, Deborah L. Feltz, Michigan State University Research has consistently found that previous performance accomplishments are the most salient factor contributing to an individual’s self-efficacy. Team research on collective efficacy has found similar results to those obtained with self-efficacy (Feltz & Lirgg, 1998). Even though there are similar antecedents that predict efficacy beliefs at different levels of analysis (Chen et al., 2002), there is a lack of research on the cross-level determinants of efficacy
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beliefs. The primary purpose of this study was to examine the effect of team performance on players’ subsequent self- and collective efficacy beliefs. Participants (N = 537) were golf, baseball/softball, and basketball athletes from 41 male and female intercollegiate teams. Within 24 hours prior to a competition, players completed a questionnaire that assessed perceptions of self- and collective efficacy. Following the conclusion of the competition, a postcompetition questionnaire was administered that assessed athletes’ self- and collective efficacy. Using game statistics, a composite measure of individual performance was computed for each athlete, adjusting for the average individual performance of the competition. A composite measure of team performance was computed for each team, adjusting for the performance of the opponent. The individual performance scores and team performance scores were standardized by sport. Multilevel modeling was used to examine the influence of team performance on subsequent self- and collective efficacy while controlling for players’ previous efficacy beliefs, individual performance, and team gender. Separate multilevel analyses were conducted for self- and collective efficacy. In accordance with previous research, team performance significantly predicted athletes’ collective efficacy. Moreover, team performance significantly predicted subsequent self-efficacy, with members of higher performing teams holding stronger beliefs in their personal capabilities than members of lower performing teams. The findings provide support for the cross-level sources of efficacy beliefs. Self-regulatory depletion and physical performance: An examination of depletion effects and trait self control as an effect modifier Clayton, Courtney S., Steven R. Bray, Kathleen A. Martin Ginis; McMaster University Baumeister’s limited strength model of self-regulation (Schmeichel & Baumeister, 2004) proposes that people have a limited capacity to exert control over tasks requiring selfregulation. When self-regulatory strength is depleted, performance on other tasks requiring self-regulation is impaired. Tangney et al. (2004) have also proposed that people vary in their dispositional capabilities to exert self-control. The purpose of this study was to examine the effects of a self-regulatory depletion manipulation on physical performance and to investigate the extent to which trait self-control predicts performance following self-regulatory depletion. Undergraduate students (N = 49) completed the Brief Self Control Scale (BSCS; Tangney et al.) and were randomly assigned to an experimental protocol where they were stratified by gender and randomized to either a cognitive depletion condition (modified Stroop task) or a control (color word) group and completed two maximal isometric handgrip exercise endurance trials separated by the cognitive task. Consistent with the predictions of the limited strength model, participants in the depletion condition showed performance decrements following the Stoop manipulation when compared to the control condition, F(1, 47) = 3.80 p = .05. Residualized change scores for the depletion and control groups were –5.02 and +5.68 s, respectively. For participants in the depletion condition, scores on the BSCS were positively correlated with physical performance (r = .44, p = .04). Results are consistent with an interpretation that performance of cognitive and physical tasks draws on the same self-regulatory reserve. People who report higher levels of self-control for everyday tasks show resistance to acute depletion effects on their physical performance. Findings have implications for understanding why people fail at self-regulation and why some people are more prone to lapses in self-control compared to others.
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A structural perspective on the generality of achievement motives across competence pursuits Conroy, David E.; Pennsylvania State University Achievement motive dispositions serve to energize and provide the initial direction for achievement behavior. Although such motives were conceived as general motivational dispositions that transcend specific achievement contexts, this proposition has never been tested. This presentation will review seminal theoretical conceptions of achievement motives, and explain how different operationalizations of the original theory have led to questions about the contextual specificity of achievement motives (and self-attributed motives in particular). One approach to resolving questions about contextual specificity involves testing the latent structure of motives rated in different achievement contexts. Participants (N = 223) rated their need for achievement (nAch) and fear of failure (FF) during academic, athletic, and extracurricular competence pursuits. Mean differences between contexts were apparent for both motives—nAch was higher in athletic than in academic or extracurricular pursuits, FF was higher in academic than in athletic or extracurricular pursuits, and FF was higher in athletic than in extracurricular pursuits (p < .05). A structural equation model was estimated with six first-order factors corresponding to the context-specific motives, higher-order factors representing general nAch and FF, and three correlations between first-order disturbances that represented context-specific variance: χ2(369) = 727.50, NNFI = .92, CFI = .93, RMSEA = .07 (90% CI = .06 to .07). Fit did not change significantly when the correlations between disturbances from corresponding contexts were constrained to zero: χ2(3) = 0.60, p > .05. The higher-order nAch factor accounted for 54%–67% of the variance in nAch within each context; the higher-order FF factor accounted for 70%–85% of the variance in FF within each context. These results indicated that, mean differences notwithstanding, general appetitive and aversive achievement motive dispositions account for more variability in self-attributed motive scores than do context-specific cues. Exercise beliefs of pregnant and nonpregnant women Cook, Brian J.; Heather A. Hausenblas, University of Florida Because pregnant and postpartum women are at high risk for physical inactivity and thus developing diseases such as obesity and diabetes, theoretically based PA interventions are needed to increase and maintain the PA behaviors and motivational determinants of this special population. The purpose of our study was to theoretically examine pregnant women’s normative, control, and behavioral beliefs guided by the framework of the theory of planned behavior (TPB). Women (N = 59; pregnant = 38, M age = 28.66; nonpregnant = 21, M age = 28.16) completed self-report assessments of TPB constructs for exercise during their first trimester. Nonpregnant controls completed similar assessments of TPB constructs for exercise during the current three-month period. Pregnant and nonpregnant women did not differ in their reporting of beliefs, χ2(7) = 5.55, p = .593. A 2 (status) × 8 (belief type) ANOVA revealed no difference in reporting belief type, F(1, 862) = .031, p = .860. Both pregnant and nonpregnant women reported more advantages of exercise. The most commonly reported behavioral beliefs were behavioral beliefs were pregnancy benefits (pregnant) and overall health benefits (nonpregnant). The most commonly reported control beliefs were difficulty exercising when feeling sick (pregnant) and difficult scheduling exercise (nonpregnant). The most commonly reported normative beliefs were approval from husbands/boyfriends (pregnant) and approval from family (nonpregnant). Further understanding of specific beliefs
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throughout each trimester and applying theoretical paradigms is needed to create more efficacious interventions for specific populations such as pregnant women. Informal roles and cohesion within sport teams Cope, Cassandra J.; Mark A. Eys, Laurentian University; Mark R. Beauchamp, University of British Columbia Informal roles evolve as a result of the interactions that take place among the members of a group. Recent research by Cope and colleagues (2007) has identified twelve informal roles that could play an integral part within sport teams (e.g., comedian, enforcer, distracter, spark plug, informal leader nonverbal, informal leader verbal, team player, star player, malingerer, social convener, mentor, and cancer). Cope et al. also noted that discussion of these informal roles often was in context of other individual (e.g., satisfaction) and group level (e.g., cohesion) variables. The purpose of the present study was to compare perceptions of cohesion between two groups: those athletes who viewed various informal roles to exist on their sport team with those who did not. Athletes from a variety of competitive levels (N = 68; males = 35, females = 33; mean age = 19.97) participated by completing a questionnaire designed specifically to assess informal roles in addition to the Group Environment Questionnaire (Carron et al., 1985) for task and social cohesion. This was conducted prior to or after a practice session. Multiple MANOVAs were utilized and indicated that group differences on cohesion were present for two of the informal roles: cancer, F(4, 61) = 2.01, p < .05, η2 = .120; and star player, F(4, 62) = 3.53, p < .05, η2 = .185. At the univariate level, those who noted the presence of a “cancer” on their team held lower perceptions of Attractions to the Group-Task (M = 5.35) and Group Integration-Task (M = 5.72) than those who did not (M = 6.49 and 6.56, respectively). In addition, those who indicated that a “star player” was present on their team (M = 5.47) held lower perceptions related to Attractions to the Group-Task than those who did not (M = 6.27). Finally, implications and future research directions are discussed. Physical activity during a time of transition: An analysis of expectant and new mom’s exercise patterns Cramp, Anita G.; Steven R. Bray, McMaster University The transition from adolescence to adulthood marks a significant trend in decreasing physical activity levels for young women (Gordon-Larsen, Nelson, & Popkin, 2004). One factor which may contribute to the decline in women’s physical activity is pregnancy and the demands of motherhood (Godin et al., 1989; Mottola, 2002). Although there are a number of studies that have demonstrated that physical activity declines during pregnancy, few studies have examined change in physical activity during pregnancy and in the postnatal period compared to pre-pregnancy levels. The purpose of the present study was to examine the trajectories of women’s physical activity across pre-pregnancy, during pregnancy and through to the postnatal period. A total of 304 pre- and postnatal Canadian women completed the 12-month Modifiable Activity Questionnaire (MAQ: Kriska et al., 1990) and demographic information. Multilevel modeling was used to estimate a growth curve representing changes in physical activity (MET hr/month) over time and the degree of individual variation over time. Time (18 × 1-month intervals) was treated as the Level-1 within-person predictor with the individual represented at Level 2. The mean growth curve estimates for the linear, quadratic, and cubic trends were all significant (p < .05), indicating that physical activity levels declined during
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pregnancy compared to pre-pregnancy levels but then increased again following birth. One demographic predictor variable (having other children at home) was significant (β01 = −.87, SE = .44, p = 05). Physical activity levels were higher for first-time mothers compared to women who had other children. Importantly, the results also showed that the base rate and slopes varied significantly across participants; Var(intercept) = 3.88, Var(linear) = .58, Var(quadratic) = .12, Var(cubic) = .01. Although physical activity generally shows accelerated decline during pregnancy, many women quickly resume activities postpartum. Changes in the forms of physical activity undertaken by postnatal women are discussed. Yoga and quality of life in cancer survivors: Room for alternative physical activity Culos-Reed, S. Nicole; Jill M. Norris, Linda E. Carlson; University of Calgary; Tom Baker Cancer Centre, Calgary; Susi Hately-Aldous, Functional Synergy Inc., Calgary Purpose: Alternative forms of PA have been seldom examined in cancer survivors. This study explored the impact of a seven-week yoga intervention on QoL and associated outcomes in a sample of off-treatment mixed-cancer survivors. Methods: Fourteen waves (n = 140) of prescreened PAR-Q/PAR MED-X participants were randomized 2:1 to the weekly 75-minute group-based intervention (YI; n = 96) or wait-list control group (WC; n = 44). Assessments at preintervention (T1) and postintervention (T2) used patient-reported demographics, PA GLTEQ, and psychological outcomes: European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 36 version 3.0 (EORTC QLQ-C30), Profile of Mood States (POMS), Symptoms of Stress Inventory (SOSI), Mindful Attention Awareness Scale (MAAS). Results: Participants were predominantly females mean 51.4 years, with a previous breast cancer diagnosis mean 31.2 months since diagnosis. Adherence was 77%, with retention at T2 81% for YI, and 70% for WC. ANOVAs were significant for total PA frequency (p = 0.04) and duration (p = 0.01), with an interaction effect for mild PA frequency (p = 0.04), mild PA duration (p = 0.01), and strenuous PA duration (p = 0.02). Specifically, the YI increased mild PA duration, mean 22.4 to 42.7 min, p = 0.005. In contrast, the WC decreased in mild PA frequency, mean 5.8 to 2.5 times/wk, p = 0.04, and increased strenuous PA duration 19.5 to 36.4 min, p = 0.04. Controlling for T1 covariates, a significant Group × Time interaction was observed for QoL (p = 0.006). Specifically, YI significantly increased QoL over the intervention mean 67.1 to 75.3; p < 0.001. Significant effects for total mood disturbance (p < 0.001), total stress (p < 0.001), and mindfulness (p < 0.001), with improvements seen in both groups. Many of the QoL, POMS, and SOSI subscales also achieved significance. Conclusions: The yoga therapy intervention was effective in improving QoL and demonstrated psychological benefits for cancer survivors. Future work must address the issue of control-group contamination. Congruency of role perceptions in intercollegiate basketball teams Cunningham, Ian J.; Mark A. Eys, Laurentian University The purpose of the present study was to explore the degree to which task-related team knowledge (i.e., role behaviors) was shared between members of competitive basketball teams. In addition, the degree to which role knowledge was shared was examined in relation to perceptions of group cohesion. Participants included basketball team members (N = 106, M age = 20.19) of five male and three female intercollegiate basketball teams. Participants were asked to rank themselves and other members on task categories relevant to formal
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roles. Visual analog scales were utilized on which participants indicated the relative rank order of group members with regard to their contribution to each task-related role responsibility (e.g., rebounding). Responses for each role responsibility were further examined to create four variables for each participant: (a) a self-ranking (i.e., how each member ranked him/herself), (b) a normative ranking (i.e., the average of all members’ rankings for each individual), and (c) a reciprocal rank (i.e., the discrepancy between the self-ranking and normative ranking). Finally, each group’s overall consensus regarding specific role responsibilities (i.e., the consistency of rankings within each group) was determined. Perceptions of group cohesion were measured using the GEQ (Carron et al., 1985). With regard to four of the five task-related role responsibilities, results indicated that team members who ranked their own contributions closer to the normative ranking (i.e., how others viewed their role) held greater perceptions of cohesion (−.30 < r < −.21; p < .05). In addition, team members who had played a greater number of years with their present basketball team were found to rank their own role-related contributions closer to the normative ranking (−.27 < r < −.22; p < .05). The results of the present study offer both theoretical and applied implications to sport group functioning through highlighting the importance of role knowledge distribution within an interactive sport team. Who chokes under pressure?: An exploration of motivation and goals as processes involved in performance under pressure. Davis Marchand, Hannah; Luc Pelletier, University of Ottawa Choking has been broadly defined as a performance decrement under pressure. We propose a unique multidimensional approach to the study of choking using the self-determination theory (SDT). The SDT proposes that individuals engage in activities for different reasons (i.e., high self-determination [because it is chosen, important or fun] versus low self-determination [to comply with external pressure, to gain a reward, to avoid guilt]). Complementary to SDT is the achievement goal theory, differentiating between ego-involved goals (self/ others focused) and task-involved goals (mastery/learning focused). We propose a model based on predispositional and situational factors using these two approaches to help explain choking under pressure. Findings represent the first two studies of a series of studies that will be conducted to test our model of choking. The purpose of Study 1 was to examine the relationship between motivation, goal orientations, and the perception of successful performance under pressure. Participants (n = 464) completed the Global Motivation Scale (GMS), the Task and Ego Orientation in Sport Questionnaire (TEOSQ), and a pressure to perform survey. Significant correlations were found between self-determination and goal orientations. Regression analyses revealed that scores on the GMS and the TEOSQ significantly predicted perception of performance. The purpose of Study 2 was to identify how motivation and specific goals interact with performance using a laboratory pressure situation. Participants (n = 100) completed the GMS and the TEOSQ, and participated in three separate trials of shooting basketball free throws, with randomly assigned task-involved or ego-involved goals. Significant correlations were found between the GMS and the TEOSQ and low self-determined participants performed significantly worse under pressure in comparison to self-determined participants. Findings indicate that motivational orientation and goals, as predispositional and situational factors, help explain choking. Practical and theoretical implications will be discussed.
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Predicting collective efficacy through team-referent causal attributions: A multilevel analysis Dithurbide, Lori; Graig M. Chow, Michigan State University; Philip J. Sullivan, Brock University Research of team referent causal attributions in sport has examined the attributional differences between successful and unsuccessful teams (Bird & Brame, 1978; Greenlees, Lane, Thelwell, Holder, & Hobson, 2005). These studies have produced inconsistent results. In addition, little is known about the consequences of the different team attributions made by successful and unsuccessful teams, for instance on collective efficacy beliefs. The goal of this study was to examine the predictive value of team-referent causal attributions on collective efficacy beliefs while controlling for subjective and objective performance. Volleyball players (N = 248) from 45 recreational teams completed a subjective team performance measure and a team-referent causal attribution scale following the first match. Objective team performance was measured by the point differential of the match. Prior to the second match, each team completed a scale measuring the team’s collective efficacy regarding the match they were about to play. Due to the nested nature of the data (individuals nested in teams), hierarchical linear modeling was used to evaluate the predictive relationship. Results indicated that at the athlete level, team control was a significant and positive predictor of collective efficacy, whereas at the team level, stability was a significant, but negative predictor of collective efficacy. However, the influence of stability on collective efficacy was moderated by subjective team performance. These results suggest that the more athletes attribute the team’s performance to team controllable factors, the more they believe in their team’s ability. For teams with higher subjective team performance, the more stable the attribution was, the higher the athlete’s collective efficacy. For teams with lower subjective team performance, the more stable the attribution was, the lower the athletes collective efficacy. Parents’ experiences of child-to-parent socialization in youth sport Dorsch, Travis E.; Alan L. Smith, Meghan H. McDonough; Purdue University Sport psychologists exploring socialization processes have largely considered how young athletes are affected by their sport involvement, not how young athletes may affect others through that involvement. To build upon the sparse literature on child-to-parent influences in sport (Snyder & Purdy, 1982; Weiss & Hayashi, 1995), we conducted an in-depth exploration of parents’ beliefs about how they are socialized through the sport participation of their children. Within a grounded theory paradigm (Strauss & Corbin, 1994), the content of five semistructured focus groups with youth sport parents (N = 26) was inductively analyzed through open-, axial-, and selective coding. Emerging themes were separated into three broad categories of perceived parental change (i.e., changes in parent affect, behavior, and cognition). Eighteen descriptive themes were coded as changes in parent affect. The consequences of parents’ changes in affect were an increased emotional tie to sport (both the setting and outcomes) and emotional growth. Twenty-three descriptive themes were coded as changes in parent behavior, contributing to changes in the parent-child relationship and social networks of parents. Ten descriptive themes were coded as changes in parent cognition, resulting in parents’ increased appreciation of sport. Findings also exhibited an interplay of parental changes. For example, communication with children led to changes in parents’ thoughts about sport, parents’ regulation of emotion influenced their behavior, and reshaping their thoughts about sport influenced parents’ expression of emotion. This
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interplay resulted in parents learning and identifying with the “youth sport parent” social role. Finally, parents perceived child age, parent sport experience, parent and child gender, child temperament, community sport context, and sport type (i.e., team or individual) to moderate their socialization outcomes. This descriptive research extends both the depth and breadth of sport socialization knowledge and opens avenues for future research on parent sport socialization. Coping in the context of dyadic sport: Relationships with dyadic motivation, cohesion, and performance. Fecteau, Marie-Claude; Patrick Gaudreau, University of Ottawa; Stéphane Perreault, University of Quebec in Trois-Rivières The coping resources an athlete can use to face a stressful situation have broadly been studied in the field of sport psychology. Little attention has been allocated to coping of athletes in a dyadic sport context. Furthermore, coping has been found to predict individual outcomes such as affect (Ntoumanis & Biddle, 1998), and psychological adjustment (Hoar & al., 2006). Motivational orientations, as defined by tenants of self-determination theory (Deci & Ryan, 1985), have been identified as antecedents of coping in competitive sport (Amiot & al., 2004; Gaudreau & Antl, in press). Up to now, these researches have focused on motivation and coping at the individual level without considering the group and dyadic levels of these processes in team and dyadic sports, respectively. The goal of this study was to examine the relationship of dyadic coping of individual athletes with their dyadic motivational orientations as well as their dyadic cohesion and performance. This study was conducted with 70 competitive athletes from 35 dyads between 14 and 24 years of age before an important event. They completed a questionnaire measuring their individual perceptions of motivation, coping, performance, and cohesion at the dyadic level. The results indicated that self-determined motivation was significantly correlated with logical analysis (r = .35); cohesion (r = .58); and performance (r = .48). Also, logical analysis was significantly correlated with cohesion (r = .58) and performance (r = .35). Moreover, regression analyses indicated that coping mediated the relationship between self-determined motivation and cohesion. These results highlight the role of coping not only in the prediction of individual-level outcomes but also in explaining cohesion and performance at the dyadic level. Also, this study extends prior research on the mediating role of coping in the relationship between motivation and indicators of dyadic adjustment. These results will be discussed in light of burgeoning literature of sport-related coping. Theoretical and methodological implications are discussed. Examining the relationship between perceived coaching behaviors and changes across a competitive season in collegiate athletes’ evaluation of their teams dynamics Fenton, Lindsay R.; Thelma S. Horn, George Pappas, Miami University Although previous research has shown that coaches’ behaviors and leadership styles have a significant effect on individual athletes’ psychosocial well-being (e.g., anxiety, self- esteem, levels of intrinsic motivation), relatively less research has been conducted to examine the effects of different types of coaching behaviors on team dynamics. The purpose of the current study was to determine if the changes that occurred across a competitive season in athletes’ evaluations of their team’s cohesion and collective efficacy could be predicted by athletes’ perceptions of their coaches’ behaviors and leadership styles. The study sample included 180 NCAA Division I college athletes from a variety of sports. Self-report questionnaires
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were administered at two time points (early and late season) during the athletes’ competitive season to assess athletes’ perceptions of their team’s cohesion and collective efficacy. Athletes’ perceptions of their coaches’ behavior and leadership style were assessed at the end of the season using the Leadership Scale for Sports (LSS) and the Coaching Feedback Questionnaire (CFQ). Multivariate multiple regression analyses revealed that athletes who perceived their coaches to exhibit higher frequencies of democratic behavior, training and instruction, social support, and positive and informational feedback showed an increase over the season in their perceptions of their team’s level of cohesion and collective efficacy. Correspondingly, athletes who perceived their coaches to be higher in autocratic behavior and to provide high frequencies of punishment-oriented feedback and nonreinforcement/ ignoring mistakes exhibited a decrease in perceived cohesion and collective efficacy over the season. The relatively large redundancy index (57.4%) indicated that the combination of coaching behavior variables accounted for a significant and meaningful amount of the variance in the changes that occurred in athletes’ perceived levels of team cohesion and collective efficacy over the course of a competitive season. Focus group methodology: Strengths and limitations in sport and exercise psychology research Fifer, Angela M.; Eric A. Bean, Dan R Gould; Michigan State University Qualitative methodologies, including observation, in-depth interviews, and video analysis, have gained substantial use and impact in sport and exercise psychology in recent years. One underused method is focus group research. It is designed to understand a phenomenon through the discussion and interaction of multiple perspectives (Morgan, 1998). This presentation will discuss the strengths and limitations of focus group research by presenting results from two studies. Advantages of focus group research include its socially oriented nature, opportunities for peer interaction, and an increased depth of information (Marshall & Rossman, 2006). Limitations of this method include the potential for a single dominant voice, participants getting off topic, a lack of depth in responses, and complicated logistics. Study 1 was designed to identify coaches’ perspectives on positive youth development (PYD) through sport. This method allowed investigators to identify a range of specific factors involved in PYD through sport (e.g., failure of league administrators to commit to a PYD philosophy, the perception that PYD coaching education content is not culturally specific). The disadvantages of focus group methodology for this study included the logistics of organizing the time and place, coaches not showing up or arriving late, and a lack of time to ask all pertinent questions. The second study focused on coaches, athletic directors, and parents’ perspectives on the role parents play in educational athletics. The study allowed participants to share common experiences while discussing and debating different perspectives. Focus groups then seemed well suited to identify a range of responses and allow participants to stimulate each others’ thoughts and responses. Chief limitations were a lack of depth in responses and a few people dominating the discussion. In the future, focus group research should include a greater focus on logistics, encouraging triangulation across various subgroups, exploring grounded theory methodology, and incorporating field notes and observation. Affective responses to 10-minute and 30-minute walks in sedentary, obese women Focht, Brian; Ohio State University
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Accumulating recommended amounts of daily physical activity (PA) through multiple 10-min walks has been proposed as an alternative strategy for facilitating the adoption of PA in obese women. Efforts to promote PA through multiple 10-min walks are based on the expectation that brief walks are more pleasant and will foster greater motivation for regular PA participation. Nonetheless, relatively little research has directly addressed this contention. Therefore, the purpose of this study was to examine differences in affective responses and proxy measures of motivation for regular participation with 10-min and 30-min walks among sedentary, obese women. Twenty-three women (M age = 26.62 years; BMI = 33.53 kg/m2) completed 10-min walk, 30-min walk, and quiet rest (QR) conditions. Affective responses were assessed prior to, during, and following each condition using the Feeling Scale (FS) and Felt Arousal Scale (FAS). Self-efficacy and intention for daily participation in multiple 10-min walks or single 30-min walks during the next month were also assessed postexercise. ANOVA analysis yielded significant Condition × Time interactions for the FS, p < 0.05, and FAS, p < 0.01. Follow-up analysis revealed that significant increases in the FS and FAS emerged during and following both the 10-min and 30-min walks, whereas no changes were observed with QR. T-test analyses demonstrated that self-efficacy (p < 0.01) and intention for future participation (p < 0.01) were significantly higher for multiple 10-min walks. Thus, although overweight women exhibited comparable affective benefits with both 10-min and 30-min walks, they reported more favorable responses on proxy measures of motivation to participate in multiple daily 10-min walks. Consequently, even though affective responses to acute exercise may be an important determinant of PA participation, the present findings underscore the importance of addressing other barriers in interventions designed to promote walking among sedentary, obese women. Understanding adolescents’ positive and negative developmental experiences in sport Fraser-Thomas, Jessica L.; York University; Jean Côté, Queen’s University Organized activities have been proposed as an effective vehicle to foster positive youth development (Larson, 2000). Past studies (e.g., Hansen et al., 2003) have examined adolescents’ development across activity contexts, but there is a need to further understand youths’ development through sport, given programs’ popularity and diversity. The purpose of this study was to gain understanding of adolescents’ positive and negative developmental experiences in competitive swimming. High-investment adolescent competitive swimmers (N = 22) of mixed genders, competencies, and clubs were purposefully sampled (Patton, 2002). Participants engaged in a semistructured interview focused on positive and negative developmental experiences in competitive swimming during adolescence. Content analysis followed previously established guidelines (Tesch, 1990). Athletes suggested that swimming fostered primarily positive developmental experiences related to a strong work ethic, meaningful adult and peer relationships, a sense of community, and other life attributes. Athletes also outlined negative experiences related to poor coach relationships, negative peer influences, parent pressure, and the psychological challenges of competitive sport. Findings suggest sport facilitates distinct developmental experiences. Athletes outlined how characteristics of their sport (e.g., early morning practices) fostered a solid work ethic and how coaches’ unfaltering belief in their abilities built their self-esteem, motivation, and determination. Further, athletes spoke of the special relationships they developed with
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their parents as a result of traveling and sharing the highs and lows of their sport with them. Athletes also suggested their swim club facilitated their sense of belonging to a larger community. Finally, some athletes discussed their inability to deal with the mental challenges of competitive sport, whereas others outlined coping skills they developed as a result of their sport stress. Findings suggest important implications for practice and interesting directions for future research. A prospective examination of social cognitive predictors of walking for active transportation Fuller, Daniel L.; Nancy C. Gyurcsik, Lawrence R. Brawley, Kevin S. Spink; University of Saskatchewan Active transportation (AT) is any human-powered transportation. Walking for AT may be a viable strategy to increase physical activity levels. Limited research has examined motivational determinants of walking for an AT purpose and found some personal variables within social cognitive theory (SCT), such as attitude and perceived barriers, predicted AT. To advance this research, reliable predictors of exercise and physical activity for fitness/health purposes need to be studied relative to their predictive utility for purposeful walking for AT. The aim of the study was to examine whether the SCT constructs of walking self-efficacy, self-regulatory efficacy (i.e., barrier, scheduling), intention, and outcome expectations, as well as perceptions of distance and time were related to walking for AT. Participants were 106 university students, faculty, and staff aged 17–55 years (n = 105; 69.8% female) who reported living within a walkable distance to the university campus. Social cognitions for a 10-day period of school/work (Monday to Friday for 2 weeks) were assessed via a baseline Web-based survey. Walking for AT over the same 10-day period was assessed via weekly Web-based surveys. Participants reported walking for AT on 4.55 days (SD = 4.12). A multiple regression analysis including all social cognitions indicated that the model accounted for 65% of the variance in walking for AT, p < .01. Barrier self-efficacy (βstd = 2.41, p < .05) and intention (βstd = 5.74, p < .01) were significant independent predictors. Barriers to walking, for which participants were least efficacious included the following: walking when feeling sick, in the dark, and when faster transportation was available. Efficacy in overcoming AT barriers and intention may be important social cognitions related to purposeful walking for AT. Future research should examine whether self-efficacy to overcome AT barriers mediates and/or a reduction in salient barriers (e.g., provision of adequate lighting) moderates the relationship between the purpose of walking (i.e., AT, health, both) and adherence to walking as a mode of AT. Relations between body dissatisfaction, motivation, and perceived autonomy support in high school physical education Gammage, Kimberley L.; Ken Lodewyk, Melissa Pirrie; Brock University In North America, enrollment in high school physical education classes has continued to decline steadily. Throughout the high school years, males consistently have higher participation rates than females, but, in both genders, enrollment rates drop each year of high school (CDC, 2007). Given the increasing rates of obesity linked with physical inactivity, it is important to examine factors that may be related to physical education participation in this age group (CDC, 2001). Body dissatisfaction (BD), the discrepancy between one’s current perceived body and one’s ideal, may be one such factor. The purpose of the present study
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was to examine the relationship between BD, motivational factors for physical education, perceived autonomy support (i.e., the extent to which students feel understand by their teachers, and feel that they have choice), and perceived achievement in physical education. A total of 216 female and 108 male grade 9 and 10 students completed a series of questionnaires in their physical education classes. For males, BD was not significantly related to motivation for physical education, perceived achievement, or perceived autonomy support. However, for females, a different pattern of results emerged. Specifically, correlations showed that BD was negatively related to self-efficacy for learning and performance in physical education (r = −.15, p = .03) and perceived autonomy support (r = −.21, p = .002), and positively related to test anxiety (r = .24, p = .002). However, it was unrelated to achievement in physical education. Results of a regression analysis showed that the overall model was significant, F(7, 187) = 2.94, p = .006, with only perceived autonomy support (β = −.18, p = .03) and test anxiety (β = .20, p = .02) making significant contributions. The findings of this study suggest that BD may be linked to important motivational variables in physical education settings. Physical educators should recognize that, in high school females, BD may be an important factor in influencing motivation within the physical education context. The relationship between frontal brain asymmetry and exercise addiction Gapin, Jennifer I.; Jennifer L. Etnier, University of North Carolina at Greensboro Previous research on the causes of exercise addiction has focused mainly on personality traits, social influences, and disordered eating (Bamber et al., 2000; Beals, 2004). However, few studies have examined the psychophysiological nature of exercise addiction. Numerous studies have repeatedly found that baseline frontal asymmetry, as measured by electroencephalogram EEG, predicts important qualities of dispositional mood, temperament, and psychopathology. A common finding across studies is greater activity at right frontal electrode sites among individuals suffering from negative affect and depression. Because a defining feature of exercise addicts is to use exercise to control negative mood states, it is expected that those with symptoms of exercise addiction will exhibit different frontal activity. The objective of this study was to explore the hypothesized relationship between exercise addiction and frontal EEG activity. Regularly physically active women (n = 29, M age = 31.64, SD = 11.31) were recruited to participate in the study. Participants completed the Exercise Addiction Inventory EAI (Terry, Szabo, & Griffiths, 2004). After completing the EAI, each participant took part in an EEG session that consisted of eight 1-minute resting trials, four with eyes open and four with eyes closed, presented in counterbalanced order. Data were collected from the left and right F3 and F4 mid-frontal sites. Based upon scores on the EAI, participants were categorized as exercise addicts (n = 10, score = 24) or symptomatic exercisers (n = 19, score of 13–23). Results showed that there was not a significant correlation between EAI score and F3 left frontal, r = .29, p > .05, but there was a significant positive correlation between EAI score and F4 activity right frontal, more negative affect, r = .38, p < .05. These findings support the hypothesis that exercise addicts would demonstrate EEG activity consistent with a need to control negative mood states and suggests that exercise addiction is similar in its psychophysiological nature to other forms of addiction. Socially prescribed perfectionism, well-being of athletes, and health-related strivings of university students: The moderating role of self-oriented perfectionism Gaudreau, Patrick; University of Ottawa; Richard Koestner, McGill University
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Research on the achievement and well-being outcomes of dispositional perfectionism remains limited in sport and exercise psychology. Nonetheless, there is now growing evidence that socially prescribed perfectionism is reliably associated with negative outcomes. In contrast, self-oriented perfectionism has been labeled as a maladaptive-unhealthy (Flett & Hewitt, 2005), adaptive-healthy (Dunkley et al., 2006), or a neutral disposition (Bieling et al., 2004). A potential explanation for these inconsistencies could be the failure to fully account for the multidimensional nature of perfectionism and, more specifically, to examine the potential interaction between the self and the social dimensions. Two studies were conducted to examine whether self-oriented perfectionism buffers the relationships of socially prescribed perfectionism with subjective well-being of athletes (Study 1, n = 208) and goal progress of university students in the pursuit of a self-set health-related goal (Study 2, n = 64). Results of moderated hierarchical regressions indicated, both concurrently Study 1 and over a fourweek period Study 2, that socially prescribed perfectionism was severely associated with lower levels of subjective well-being (β = −.48, p < .01) and health-related goal progress (β = −.53, p = .05) for individuals who were low on self-oriented perfectionism. As expected, the thwarting association with well-being (β = −.22, p < .05) and goal progress (β = .28, p = .09) was strongly attenuated for individuals who were high on self-oriented perfectionism. These results indicate that labels such as neurotic or unhealthy should be limited to a clear-cut style of socially prescribed perfectionism, i.e., high on socially prescribed and low on self-oriented perfectionism rather than to people with a mixed profile of perfectionism, i.e., high on both socially prescribed and self-oriented perfectionism. The dynamics of goal involvement states in table tennis: The role of the historicity of scoring Gernigon, Christophe; Walid Briki, University of Montpellier 1; Katie Eykens, Catholic University of Leuven Research conducted in a natural sport context has shown that goal involvement states can undergo some abrupt variations (Gernigon, d’Arripe-Longueville, Delignières, & Ninot, 2004). Based on the dynamical systems perspective, the purpose of the present study was to experimentally investigate the influence of the historicity of scoring on the flow of goal involvement states in table tennis. Twenty-three male table tennis players, either regional or national level, had to empathize with a highly important contest by watching two video scenarios of a table tennis game in two sessions separated by one month. The videos presented two inverted and symmetrical scenarios in which score gaps gradually varied in increasing versus decreasing ways. Based on Elliot and McGregor’s (2001) model, goals of performance-approach (PAp), performance-avoidance (PAv), mastery-approach (MAp), and mastery avoidance (MAv) were assessed through single items before each point. Multivariate and univariate analyses of variance (p < .05) revealed some abrupt changes according to the score gaps for MAv, thus allowing to class this goal as a psychological content of momentum in sport (e.g., Perreault, Vallerand, Montgomery, & Provencher, 1998). Only PAp and MAv goals were sensitive to the historicity of scoring, displaying their highest scores in the increasing scenario and in the decreasing scenario, respectively. Moreover, MAv goals displayed a hysteresis pattern. These findings encourage further research on psychological momentum in sport based on the dynamical systems approach. Social cognitive and control theory: A test of self-efficacy and performance in strength and conditioning Gilson, Todd A.; Deborah L. Feltz, Michigan State University
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Research, along with anecdotal evidence, has argued that self-efficacy is a key component when it comes to measuring performance in sport. Presently, social-cognitive theory (SCT: Bandura, 1986, 2001) and perceptual control theory (PCT: Powers, 1978, 1991) differ in how each explains the manifestation of confidence in individuals who are repeatedly tested at a skill/task over a period of time. Specifically, Bandura and Locke (2003) found that selfefficacy has been consistent in its significant contribution to motivation and performance over a series of nine meta-analyses. In contrast, Vancouver and colleagues revealed that self-efficacy was negatively related to performance at the within-person level over time, but was positively related to performance at the between-person level (Vancouver & Kendall, 2006; Vancouver et al., 2001, 2002). In this study, 115 Division I collegiate football players from 5 universities (M age = 20.55, SD = .966) completed a self-efficacy measure within 72 hours of a 1-repetition max test in the squat at three time points during off-season training. Utilizing a linear growth model with HLM, results revealed that self-efficacy was nonsignificantly positively related to squat performance (p = .118) at the within-person level and significantly related to performance between-persons (p < .01) when controlling for athletes’ raw past performance. Furthermore, 17.7% of the Level 1 variance and 99.8% of the Level 2 variance surrounding current performance was explained with self-efficacy and raw past performance included in the model. Although results did not fully support either theory at the within-person level, they were in the opposite direction of what Vancouver et al. predicts within PCT. This study helps further the understanding concerning the relationship between self-efficacy and performance when using a unique real-world task that is less cognitively demanding and allows for changes in performance over time. Struggling with decisions about exercise therapy: Relation of efficacy and thought valence Glazebrook, Karen E.; Lawrence R. Brawley, University of Saskatchewan Previous social cognitive research in the asymptomatic population has shown that exercisers experience both acute positive and negative thoughts when contemplating their upcoming exercise. Acute positive thinking is related to lower decisional struggle, greater self-efficacy, and more consistent exercise behavior (Gyurcsik, Brawley, & Langhout, 2002). Selfregulatory efficacy (SRE) is crucial for adherence to rehabilitative exercise (e.g., cardiac: Berkhuysen et al., 2001; Woodgate & Brawley, in press); however, these studies have not examined either thoughts or decisional struggle in relation to SRE. Our purposes were to (a) examine social cognitive differences in positive/negative thinkers and (b) identify variables related to extent of decisional struggle and SRE among individuals participating in a structured center-based exercise program for disease prevention and rehabilitation. Forty-four participants were asked to record positive and negative thoughts about exercise at the program for the next 2 weeks, and the extent to which these thoughts made them struggle with their exercise decisions. Exercise SRE (scheduling) was measured relative to the same time frame. MANOVA revealed that negative thinkers (i.e., the valence of total thoughts was more negative than positive) experienced significantly more decisional struggle and had lower self-regulatory efficacy than positive thinkers (Wilks’s Λ = .769, p = .005). Decisional struggle and overall thought valence were correlated (r = −.423, p = .004). Multiple regression analysis indicated that SRE for upcoming exercise was significantly predicted by overall thought valence and decisional struggle (R2 adj. = .317, p < .001). Together, these results agree with previous research on acute positive and negative cognitions and extend the findings to the context of rehabilitation exercise therapy. Future research should examine what moderators prompt negative thinking in this population (e.g., experiencing a lapse; beginning vs. maintaining rehabilitation) given its relationship to lower SRE.
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Dissecting the “obesogenic” environment of a psychiatric hospital Gorczynski, Paul; Guy Faulkner, Laura Zeglen; University of Toronto; Tony Cohn, Centre for Addiction and Mental Health There is a higher prevalence of obesity and obesity-related diseases in individuals with serious mental illness in comparison to the general population. The purpose of this study was to examine the “obesogenic” factors, environmental influences on diet and physical activity that contribute to obesity, in the inpatient setting at one large psychiatric hospital. A qualitative approach was adopted and 25 semistructured interviews were conducted with a range of key stakeholders at the hospital. Interviews were audio-recorded and transcribed verbatim. Transcripts were analyzed through content analysis using the analysis grid for environments linked to obesity (ANGELO) framework as a categorical template (Swinburn, Egger, & Raza, 1999). In total, 54 factors related to food consumption and 30 factors related to physical activity or sedentary behavior were reported. Five valid, relevant, and modifiable factors included: (1) staff shortages; (2) inconsistent treatment delivery across all units; (3) a lack of educational programs for clients about diet and physical activity; (4) the nature of food services delivery; and (5) the client and survivor run food operations. Overall, interviewees noted that obesogenic factors related to diet had a greater impact on weight gain than sedentary behavior. However, many stressed the importance of addressing both in order to decrease obesity in the service user population. Obesogenic factors were extremely interconnected and mutually reinforcing. This highlights the need for greater interprofessional collaboration in reducing obesity prevalence in psychiatric settings. Does weight status moderate the motivation–physical activity relationship? Grattan, Kimberly; Philip M. Wilson, Brock University; Chris M. Blanchard, Dalhousie University; Samantha C. Major, Brock University Previous research supports the importance of physical activity as a mechanism for health promotion (Bouchard et al., 2007) yet few attempts have been made to understand the influence of weight status on the motivation–physical activity relationship (Blanchard et al., 2005). This study tested the moderating effects of weight status on the motivation–physical activity relationship. Participants were male (n = 297) and female (n = 1,724) employees of the American Cancer Society who ranged in age from 19 to 79 years (M = 40.26 years; SD = 11.42). Body mass index (BMI) values were slightly greater than the healthy range for this age cohort (M = 26.32, SD = 5.81). Participants completed the Behavioural Regulation in Exercise Questionnaire (BREQ; Mullan et al., 1997) and the Godin Leisure Time Exercise Questionnaire (GLTEQ; Godin & Shephard, 1985) on a single occasion. Preliminary analyses suggested no particular areas of concern with the fit of the BREQ or full measurement models (CFI/NNFIs = 0.94; RMSEA 90% CIs = 0.06–0.08; SRMSRs = 0.05) across subgroups stratified based on BMI values. Results of the simultaneous multigroup covariance analyses supported the partial invariance of a structural model whereby identified regulation (βs ranged from .43 to .44 across BMI subgroups; ps < .05) was the strongest predictor of regular physical activity (R2 ranged from .23 to .29 across BMI subgroups) irrespective of subgroup membership (change in CFI = −0.01). Overall, the results of this investigation suggest that the relationship between motivation and physical activity behavior is not moderated by weight status classified on the basis of BMI risk profiles. Furthermore, these findings corroborate the worth of identified regulation as a motivational basis for physical activity behavior and imply that the degree of self-determination regulating physical activity
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appears more relevant than the intrinsic or extrinsic nature of the motivation itself. Funding for this study was provided by the American Cancer Society and SSHRC. Dimensions of perceived coaching style and athlete motivation: A self-determination theory perspective Gregson, Paige; Philip M. Wilson, Brock University Previous commentary indicates that sport participation is a complex process susceptible to the influence of a coach’s interpersonal style (Vallerand, 2007). The purpose of this study was to examine the relationship between markers of perceived coaching style (namely, autonomy support, structure, and involvement) and motivation indices using a framework drawn largely from self-determination theory (SDT; Deci & Ryan, 2002). Participants (N = 82; 53.7% female) were Canadian interuniversity rugby players aged 18 to 27 (M = 20.04; SD = 2.62) who completed a multisection questionnaire at the mid-point and end of their competitive season. Intraclass correlation coefficients (ICC) indicated moderate stability across perceived coaching style and psychological need satisfaction indices over time (ICCs = .58 to .75). Hierarchical multiple regression analyses (HMRA) controlling for demographic and training variables indicated that perceived involvement of the head coach predicted effort put forth within sport by athletes at the midpoint (R2 adj. = .31; β = .24) and end of season assessments (R2 adj. = .21; β = .22). Additional HMRAs indicated that perceptions of competence and relatedness to fellow team members predicted the majority of variance in more self-determined motives to continue playing rugby the following season (R2 adj. values ranged from .20 to .38; βs ranged from .27 to .49, respectively). In line with previous research (Deci & Ryan; Vallerand), the results of the present study illustrate the dynamic nature of perceived coaching style and psychological need fulfillment over time in sport and imply that coaches who display empathy and genuine interest will likely motivate athletes to work harder during the competitive season. Furthermore, these findings also suggest that an enhanced sense of connection with other athletes in association with feeling effective in mastering challenging tasks is an important consideration for athletes when making decisions to continue sport involvement in future seasons. Funding for this study was provided by the SSHRC Predictors of well-being in persons with osteoporosis: Associations with demographic, health, and physical activity indices Gunnell, Katie E.; Diane E. Mack, Philip M. Wilson, Kristin G. Oster, Kimberly P. Grattan; Brock University The purpose of the investigation was to identify demographic, health, and physical activity correlates of psychological health in Canadians diagnosed with osteoporosis. Participants were 1,538 (nmale = 167; nfemale = 1,371) self-reported osteoporotics over the age of 51 (Md = 71 years) or older who participated in the Canadian Community Health Survey Cycle 2.2. Participants provided data concerning demographics (e.g., gender, age, marital status, educational attainment, and annual household income), health indicators (e.g., body mass index [BMI], smoking status, and high blood pressure), physical activity (i.e., estimated daily energy expenditure over three months), and indices of psychological health. Bivariate correlations revealed a pattern of weak to small relationships between physical activity behavior and psychological health (rs ranged from −.04 to −.29). Simultaneous multiple regression analyses accounted for 4 to 23% of the variance in markers of psychological health using
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demographic, health, and physical activity variables. Controlling for key demographic and health variables (p < .05), the unique variance accounted for by physical activity ranged from R2 change = 0% to 4% across regression equations. The meaningfulness of physical activity on psychological health was not uniform across all indices examined. Given that physical activity is advocated as a key component in intervention programs targeting either prevention or maintenance of osteoporosis and its comorbidities (Osteoporosis Canada, 2007), sustained research on the effectiveness of physical activity on promoting psychological health in people living with osteoporosis is warranted. This research was supported by the Social Sciences and Humanities Research Council of Canada. The use of observational learning in sport officials Hancock, David J.; Amanda M. Rymal, Diane M. Ste-Marie; University of Ottawa Observational learning (OL) is an evolving area within the sport psychology literature; OL is observing oneself or others, either live or on videotape, performing a task. Within the sport context, Cumming, Clark, Ste-Marie, McCullagh, and Hall (2005) have developed the Functions of Observational Learning Questionnaire (FOLQ), which identifies three functions of OL. The three functions of OL are skill, strategy, and performance. The skill function refers to observing and learning technical aspects of the sport. The strategy function refers to observing and learning the in-game strategies or game management, and the performance function denotes observing and learning how to obtain proper mental states required for performance. These functions of OL have been researched with athletes (Cumming et al.; Wesch, Law, & Hall, 2007); however, the functions of OL employed by sport officials have yet to be explored. Therefore, the purpose of this research was to examine whether sport officials utilize OL to increase officiating performance. Specifically, we asked whether officials use the functions of OL and, if so, is one function used more than another. To achieve this, the FOLQ (Cumming et al.) was administered to sport officials from a variety of sports. Participants rated, on a 7-point scale, their use of OL for the specific function described in the statement. Analysis of variance indicated a significant, F(2, 50) = p < .01, difference between all three functions of OL. The sport officials employed the skill function (M = 5.3, S = 1.1) significantly more than the strategy (M = 4.8, S = 1.0) and performance (M = 4.1, S = 1.2) functions of OL. Participants also utilized the strategy function (M = 4.8, S = 1.0) significantly more than the performance function (M = 4.1, S = 1.2). Discussion will consider the use of OL by sport officials and the implications of these findings. Elite female adolescent athletes perceptions of the motivational influences and social support of coaches, parents, and peers: A grounded theory approach Hassell, Kristina A.; Catherine M. Sabiston, Gordon A. Bloom; McGill University Self-determination theory (SDT; Deci & Ryan, 1985) research in sport has been directed almost exclusively towards the motivational influence of the coach (e.g., Vallerand, in press; Mageau & Vallerand, 2003). Parents’ and peers’ motivational influences, although important, have been studied to a much lesser extent (e.g., Gagné, Ryan, & Bargmann, 2003; Ntoumains & Duda, 2005). In addition, most recent research on social influences and self-determined motivation in sport with youth has been nomothetic and quantitative—disregarding youths’ meanings and interpretations of their social context (Garcia Bengoechea & Strean, 2007). Therefore, this presentation will focus on findings from a study which explored elite female adolescent swimmers’ perceptions of the motivational influences of their coaches, parents, and peers using a constructivist grounded theory approach (Charmaz, 2000). Nine elite
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female swimmers (aged 13–15 years) participated in two semistructured interviews that were audiotaped and transcribed verbatim. Six categories emerged, including individual factors, and social aspects, including assistance, informational, esteem, emotional, and network support. Results indicated girls’ unique interpretations of social support types and highlighted the differential importance of coaches, parents, and peers as salient providers. Swimmers’ social support experiences were uniquely linked to their perceptions of competence, autonomy, relatedness, and motivation in elite competitive swimming. These findings were consolidated into separate models linked to social support providers, which incorporated past SDT theoretical tenets and offered new insights into the important and differential influences of coaches, parents, and peers in youth elite sport. The influence of team perceptions and leader efficacy on team-referent attributions Hepler, Teri J.; Graig M. Chow, Deborah L. Feltz; Michigan State University Research has demonstrated that attributions are important factors in sport (McAuley, 1992). Recently, there has been growing interest in team-referent attributions (Greenlees et al., 2007). Most of this research has focused on differences in attributions based on outcome or gender. However, group perceptions and leader efficacy may also predict team attributions. The purpose of this study was to explore the predictive strength of team perceptions and coach efficacy on team-referent attributions. Participants included 537 intercollegiate athletes from 41 teams and their head coaches (golf, basketball, baseball/softball). Questionnaires assessed self-efficacy, collective efficacy, group cohesion, and coaching efficacy before a competition and team attributions afterward. The CDS-II (McAuley, Duncan, & Russell, 1992), which measures attributions, was modified to fit teams and three items were also added. These items assessed if the attributions were team-focused or self-focused. Multilevel modeling was used to analyze the data. Individual factors such as perceptions of individual success and self-efficacy were used as control variables. Results indicated that team perceptions and leader efficacy significantly predicted team attributions. Members of teams with higher collective efficacy made attributions that were more internal, team controllable, and team-focused than members of teams with lower collective efficacy. For group cohesion, individual attraction to the group–task was associated with less internal, team controllable and team-focused attributions. Moreover, athletes who played for coaches with high coaching efficacy attributed their team’s performance to factors that were more internal, team controllable, and less externally controllable. Finally, teams that perceived their performance as successful made more stable, externally controllable, and team-focused attributions. The findings of this study suggest that team and leader perceptions should be considered when examining team-referent attributions in team sports. Are proximal outcome expectancies and value associated with exercise identity? Linking self-efficacy theory to identity Jung, Mary E.; Lawrence R. Brawley, University of Saskatchewan; Shaelyn M. Strachan, University of Ottawa Role identities are considered essential components to one’s concept of self. Endorsement of a particular identity provides value to past behavior and directs future behavior in that individuals seek identity-behavior congruence (Anderson & Cychosz, 1995; Strachan, Jung, & Brawley, 2007). Determining which adherence-related social cognitions are associated with exercise identity (EXID) may clarify the relations between the more stable construct of identity and specific social cognitions. For example, strong endorsement of an EXID
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has been related to self-regulatory exercise efficacy (Strachan, Brawley & Woodgate, 2005, Strachan, Jung, & Brawley, 2007). However, the link between EXID and other self-efficacy theory variables (Bandura, 1986), such as outcome expectancies (OE) and value (OV), has not been examined. Theoretically, individuals who expect positive proximal outcomes from exercise and value these outcomes should wish to identify themselves as exercisers. The relationships between EXID, OE, OV, and self-regulatory efficacy were explored in a sample of 325 university students (M age = 24.9; 217 females). Participants completed one online questionnaire at the beginning of the academic year. A hierarchical multiple regression predicting EXID was performed. Self-regulatory efficacy was entered in Block 1. Proximal physical, social, and psychological OE and OV were entered in Block 2. The overall model was significant, F = 165.5(1, 324), adj. R2 = .44, p < .001. Self-regulatory efficacy explained 34% of the variance of EXID (B = .l38, p < .001). After controlling for efficacy, OE and OV explained an additional 11% of the variance (social OE, physical OE, and OV were main contributors; B = .28, −.15, and .22 respectively, p < .05). Findings confirm past research associating EXID and self-regulatory efficacy, and offer the first support for the OE, OV, and EXID relationships. Future research using a prospective design should determine the direction and strength of this latter relationship and consider when proximal OE matter for identity-behavior congruence. There is no “I” in team: Reconceptualizing immoral sport behavior as an interpersonal construct. Kaye, Miranda P.; Pennsylvania State University Moral issues are inherently interpersonal as immoral behaviors are actions that affect the material or psychological well-being of other people (Kohlberg, 1971) and are judged by their consequences to others (Haidt et al., 1993). Immoral sport behaviors may be considered interpersonal in nature in two ways. First, they focus on the violations of others’ rights such as having fair competition; an equal opportunity to strive for success; being safe from malevolence and degrading treatment or punishment; and being treated with dignity (Seefeldt & Martens, 1979). Second, immoral sport behaviors vary in their blend of agency and communion, thus potentially mapping onto a circumplex structure. There is general agreement that the appropriate structural model for representing interpersonal issues is a two-dimensional circumplex in which variables are ordered in a circular arrangement around the orthogonal dimensions of agency and communion (Wiggins, 1979). Circumplex models are well established in several psychological domains (i.e., interpersonal problems, traits, values, and social support) and may well serve to organize immoral sport behavior. This work proposes the circumplex as a theoretical model for the organization and understanding of immoral sport behavior. Items for an instrument to measure interpersonal immoral sport behavior were developed, including previously studied behaviors such as cheating and aggression as well as unstudied interpersonal behaviors such as acquiescence and melodramatic exhibition. A list of items representing the proposed categories of immoral sport behavior was developed and the psychometric properties were examined. Construct validity was assessed through associations with related measures (aggression, sportspersonship, and hypercompetitiveness) and to potential correlates of immoral sport behavior (personality, achievement motives and goals, anxiety, and social desirability). Initial results indicate support for the interpersonal nature of immoral sport behavior.
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Dispositional reinvestment and choking in cognitive and motor tasks of varying complexity Kinrade, Noel P.; Brunel University; Robin C. Jackson, University of Hong Kong; Kelly J. Ashford, Brunel University Performance breakdown under pressure has received considerable interest over the past two decades. This has generated a considerable body of evidence in support of “explicit monitoring” theories of choking. The purpose of the present study was to examine the predictive validity of the Reinvestment Scale in cognitive and motor tasks of varying complexity. This scale was designed to predict susceptibility to skill failure but has only been assessed using well-learnt proceduralized motor skills. In the present study, university students (N = 60) completed low- and high-complex motor tasks (pegboard and golf putting), psychomotor tasks (card sorting at two levels of complexity), and working memory tasks (modular arithmetic at two levels of complexity). The test battery was completed on two occasions, once under low pressure and once under high pressure. Results indicated that performance deteriorated under pressure in the pegboard task but not in the golf putting task. In the low-complex card-sorting task, performance was stable across pressure conditions; however, participants performed faster but with more errors in the high-complex version of the task. In the modular arithmetic tasks, the mean number of errors increased more under pressure in the complex version than in the simple version of the task, but completion time was unaffected. Reinvestment Scale scores were significantly related to skill failure under pressure in both the pegboard and golf putting motor tasks; were associated with faster task completion times under pressure in the low-complex and high-complex card sorting tasks (but not with change in errors); and were associated with the increase in errors under pressure in both modular arithmetic tasks (but not with change in completion time). These results are inconsistent with the Reinvestment Scale predicting conscious processing per se; rather, it predicts more general performance changes that result from increased pressure, be it speeding up of performance (card sorting) or the increased number of errors made (modular arithmetic). The two-component model of self-presentation: Examination of a weightlifting stereotype Kossert, Amy L.; Krista J. Munroe-Chandler, University of Windsor Self-presentation is the mechanism by which individuals attempt to monitor and control impressions formed of them by others (Leary, 1995). Substantive evidence suggests that, regardless of gender, self-presentational advantages exist for exercisers (Martin et al., 2000). Although this exerciser stereotype has been well documented, stereotypes proscribed to weightlifters (WL) have received considerably less attention. Thus, the purpose of this study was to examine whether the provision of an individual’s weight lifting habits influences the impressions that others form of that individual, and if those impressions are moderated by self-presentational motives. Male and female undergraduate students (N = 195) were presented with one of four vignettes depicting a male target who was described as an excessive WL, a typical WL, a non-WL, or a control. Participants rated the target on a series of personality and physical characteristics, and completed an adapted version of the Self-Presentation in Exercise Questionnaire (Conroy & Motl, 2000), modified for weight lifting. Results indicated that the excessive and typical WL targets were perceived more
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favorably in comparison to their non-WL and control counterparts in terms of both physical and personality attributes (p < .01). Although the motivation to self-present as a WL did not moderate impression formation based on WL habits information, a significant interaction emerged between impression construction and target type for one physical characteristic specific to attractiveness (p < .017). Participants high in the inclination to construct the image of being a WL attributed more favorable physical features to the excessive and typical weightlifters, in comparison with the non-WL and control targets. Results not only suggest that a social advantage is associated with being perceived as a WL, but also offer preliminary evidence that self-presentational motives may moderate the physical appearance attributed to men of varying musculature. Students with attitude: A retrospective examination of social cognitive variables that influence physical activity behavior during students’ transition from high school to university Kwan, Matthew Y.W.; University of Toronto; Steven R. Bray, McMaster University The transition from high school to university is one timeframe during which researchers have observed an abrupt decline in physical activity (PA) (Bray & Born, 2004), yet factors contributing to this decline are poorly understood. Retrospective examination of factors related to PA among students who are active compared to those who are inactive may be informative. The purpose of this case-control study was to compare active students (>4 days of 30 min of moderate/vigorous PA) and inactive students on selected social cognitive variables and relationships between those variables and PA. Two hundred and twelve first-year university students (female, n = 145) aged 17–19 (M = 17.79 ± .58), voluntarily participated. A MANOVA was computed to compare students’ scores on attitudes, subjective norms, perceived control, and intentions. The overall model was significant, F(4, 207) = 3.46, Wilks’s Λ = .094, p < .01, showing differences in subjective norms, perceived behavioral control, and intentions (ps < .01). Separate multiple regression analyses were conducted to predict students earlier intentions to be physically active. Results of both models were significant (p < .001). For students who were active, 44.5% of the variance in intentions was explained by one predictor: attitudes (β = .61). For insufficiently active students, 34.5% of the variance was explained by a combination of attitudes (β = .29), subjective norms (β = .18), and perceived behavioral control (β = .35). Thus, students who were active during their first semester at university had more positive PA cognitions going into university and a strong attitude-intention relationship. Given the high social and environmental volatility and vulnerability involved in adjustment to first-year university, PA promotion efforts in university should focus on personal evaluations and outcomes expectancies for PA to help bolster positive attitudes to be physically active. The effects of experimenter gender on state social physique anxiety and strength in a testing environment Lamarche, Larkin; University of Toronto; Kimberley L. Gammage, David A. Gabriel; Brock University Self-presentational concerns can influence actual effort put forth during exercise (Rhea et al., 2003; Worringham & Messick, 1983). Social physique anxiety (SPA), concerns over one’s body being evaluated by others (Hart et al., 1989), is a specific self-presentational concern that may be particularly relevant in a physical testing environment. A factor that may
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influence SPA, which may in turn influence the outcomes of a physical test, is experimenter gender. The present study examined the influence of experimenter gender on SPA and actual muscle strength in an experimental testing environment. Male (n = 49) and female (n = 51) university students were randomly assigned either a male or a female experimenter such that there were equal numbers of male and female participants in each condition. Prior to a strength test, a single-item measure of state social physique anxiety (SPA-S) was completed. Actual strength was represented by participants’ maximum voluntary contraction (MVC)-100 values. A MANOVA was conducted with participant gender and experimenter gender as the independent variables and strength and SPA-S as the dependent variables. Results revealed a significant gender of the participant, F(2, 94) = 23.11, p < .001, and gender of the experimenter F(2, 94) = 3.09, p = .05, effect. Follow-up univariate ANOVAs indicated that MVC-100 values were significantly higher for men (p < .001). However, although the overall effect of experimenter gender was significant, univariate follow-ups showed no significant differences with regard to strength or SPA-S between those having a male or female experimenter. Although the gender of the experimenter did not influence SPA-S or muscle strength, other forms of anxiety (i.e., performance anxiety) may have been more relevant in the testing setting. It is important to investigate other factors in the testing environment (e.g., type of task, number of observers present) which may be more influential on psychological or performance outcomes. Research supported by NSERC. Attention and movement variability: Facilitation of compensatory mechanisms under optimal attentional focus Land, William; Gershon Tenenbaum, Florida State University The study of expert performance has been examined by multiple scientific disciplines, each with their own unique level of analysis. However, up to this point, there has been little research that has attempted to illuminate the interaction between cognitive and more biomechanical systems in the production of skilled movement. Specifically, a firm link between the role of attention and variability of the motor system has yet to be established. The present study examined novice (n = 24) and skilled golfers (n = 20) on a putting task while performing under a discrete and continuous secondary task designed to aid external focus. Putting performance was measured via both a product- and process-oriented approach, which provided a comprehensive account of performance under optimal and nonoptimal focus. Results revealed that under both “optimal” external focus manipulations, skilled performance improved accompanied by increased variability in key kinematic parameters associated with the putting stroke. The increased movement variability associated with improved performance suggests that optimal attentional focus may facilitate functional and compensatory mechanisms that can aid overall performance. In contrast, novice outcome performance was unaffected by the “nonoptimal” secondary task demands, but exhibited decreased movement variability. We suggest that the increased task demands brought about by the secondary tasks resulted in novices freezing degrees of freedom in order to reduce task complexity. Overall, these findings highlight the relationship between attention and compensatory variability, and suggest that attentional focus may be vital to facilitating compensatory mechanisms in the motor system. Athletes’ use of modeling in injury rehabilitation Law, Barbi; Queens University; Craig Hall, University of Western Ontario
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Previous examinations of athletes’ use of modeling in natural sport environments have focused on the functions that it serves in practice and competition contexts (Cumming, Clark, Ste-Marie, McCullagh, & Hall, 2005; Hall et al., 2006; Wesch, Law, & Hall, 2007). Through the use of surveys, Cumming et al. (2005) found that athletes reported using modeling to aid the learning and performance of specific skills and strategies, as well as to attain optimal mental states for performance. However, athletes may also benefit from modeling in other sport-related contexts. The purpose of this study was to gather descriptive data on athletes’ use of modeling in injury rehabilitation. As part of a larger qualitative study, eleven varsity athletes (6 male, 5 female) participated in semistructured interviews about when, where, why, what, and who they observe in relation to several sport-related contexts. With respect to the use of modeling during injury rehabilitation, content analysis of the interview transcripts provided descriptive information on the structure (i.e., frequency and duration) and content (i.e., modality and focus of attention) of their modeling experiences. Athletes also described the specific types of models they observed and identified the functions modeling served for them during injury rehabilitation. Results are discussed in terms of directions for future research and possible applications of modeling throughout the injury rehabilitation process. Personal and contextual determinants of elite young athletes persistence in versus dropping out of national training centers Le Bars, Hervé; Christophe Gernigon, Grégory Ninot; University of Montpellier 1 The aim of this study was to examine whether elite young judokas (M age = 17.9) who persisted in national training centers (n = 52) were different from dropouts (n = 52) in their perceptions of coach-, parent-, and peer-induced motivational climates, goal orientations, self-perceptions, perceived competence, and intention of dropping out. Participants completed the following set of questionnaires six times during a period of two years: SOGIRSQ (Le Bars, Ferron, Maïano, & Gernigon, 2006), French versions of the POSQ (Durand, Cury, Sarrazin, & Famose, 1996) and of the PSPP (Ninot, Delignières, & Fortes, 2000), two items of perceived competence in judo, and two items of intention of giving up high level judo. For dropouts, the last measures that were recorded before they gave up were considered for the analyses. For persisting athletes, the times of measurement that were retained were yoked to dropouts. Self-perceptions were higher for males than for females but did not differ according to dropout versus persisting status. Compared to persisting athletes, dropouts perceived the roles of all the significant others as less task-involving, were less task-oriented, and intended more to drop out. No differences were observed regarding ego orientation and perceptions of ego-involving climates which were high for both samples. Dropping out or persisting might thus be more a matter of capacity to endure the difficulty of elite context, thanks to the emphasis on task perspective, rather than a matter of perception of it as more or less ego-involving. Development and validation of the collective efficacy scale in football Leroux, Mathieu; Université du Québec à Trois-Rivières Introduction: Collective efficacy has been defined by Bandura (1997) as a group’s shared belief in its own collective ability to organize and execute a course of action to produce a given level of attainment. Because high collective efficacy teams possess major advantages
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on low collective efficacy teams (Greenlees, et al., 2000; Hodges et al., 1992), it seems necessary develop a valid means of evaluating team collective efficacy in sport. In football, Myers et al. (2004) developed a scale measuring efficacy solely for offensive unit. However, this game is interdependent in nature and requires three separated units (the offensive, the defensive, and the special teams). The aim is to present the results of a sport specific collective efficacy scale in football. Method: Based on a literature review and interviews with six experienced players (college to professional level), 63 items were developed. Second, items were assessed for face and content validity by five football coaches. This step eliminated nine items and led to 54 test items. Following this steps, the remaining items were submitted to a sample of 820 players from 19 teams (M = 18.9 years old, SD = 1.9). Analysis and Results: First, item analysis was conducted using Rasch modeling, a model from item response theory. Results from this modeling procedure rejected 11 items, yielding a final version of this scale composed of 43 items, 23 items (specific to the offensive unit), 17 items (specific to the defensive unit), and 3 (specific for the specials teams). Response scale ranges from 0 to 10 (M = 7.56 and SD = 1.1). The person reliability coefficient and item reliability demonstrated good psychometric qualities (0.96 and 0.99). Results from the confirmatory factor analysis showed that a hierarchical first-order model best fitted the data (NNFI = 0.95 and SRMR = 0.066). Discussion: Strengths and limits will be discussed in addition to the use of this newly developed scale as a diagnostic tool for coaches and sport psychologists when attempting to improve confidence in football team. Skilled memory performance in soccer coaches and players Locquet, Claire; Université de la Méditerranée; Bachir Zoudji, Université de Valenciennes et du Hainaut Cambrésis; Allistair P. McRobert, Paul Ford, A. Mark Williams, Liverpool John Moores University; Hubert Ripoll, Université de la Méditerranée We examined skilled memory performance in intermediate level soccer coaches (n = 11) and players (n = 10) using a novel modification of the traditional recognition paradigm. In the viewing phase, participants were presented with 30 min of continuous film footage from the first half of a televised professional soccer match. The subsequent recognition phase contained 36 discrete trials each lasting between 8 and 12 s. Altogether, 24 sequences had been seen previously in the viewing phase and the remaining 12 sequences were new and taken from the remaining 15 min of the same half. During the entire test procedure, visual point-of-gaze data were recorded using a head-mounted, corneal reflection system. Participants were required to indicate whether or not they had previously viewed the sequences presented in the recognition phase. The dependent measures were recognition accuracy (RA), and the location, number, and duration of fixations. A mixed 2-way ANOVA was employed to assess RA with group (coaches vs. players) as a between-participant and condition (seen vs. new) as a within-participant factor. There was a significant main effect for Group, F(1, 19) = 8.0622, p = .01048. The soccer coaches (M = 76%, SD = 5) recorded higher accuracy scores than players (M = 66%, SD = 7). There were no other significant effects. The visual point-of-gaze data indicated that the coaches employed fewer fixations of longer duration and spent less time fixating on the ball than the players. The results suggest that coaches develop refined memory structures that enable them to more accurately recognize match action sequences than players. Implications for the training and development of coaches are discussed.
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Tactical bias in professional tennis: Generalized hitting preferences causing the lefthanders’ advantage in interactive sports? Loffing, Florian; Norbert Hagemann, Bernd Strauss; University of Münster Many interactive sports like tennis, table tennis, or cricket are characterized by a higher incidence and a higher-than-average rate of success of left-handed professionals, respectively. Following the strategic advantage hypothesis (Wood & Aggleton, 1989), left-handers take advantage of having different angles of attack and mirrored stroke or shot movements compared to their right-handed competitors. As right-handers are overrepresented, athletes are supposed to be more familiar with their playing techniques and tactics leading to a leftright bias, which is characterized by an imbalance in the proportion of attacking putative weak areas of the opponent. As a consequence, we hypothesize a tactical bias in athletes’ behavior when facing a left-hander; i.e., competing against a left-hander in tennis leads to a decrease in proportion of balls played to the commonly weaker backhand side compared to when playing against a right-hander. A total of N = 24,068 ball placements (n = 3,127 left-left, n = 11,671 left-right, and n = 9,270 right-right constellations) of 54 randomly chosen professional tennis matches from ATP, WTA, and Grand Slam tournaments were analyzed (data of ball coordinates by courtesy of Hawk-Eye Innovations). According to the lateral displacement relating to the midline of the tennis court, ball bounces were classified as backhand vs. forehand placements in the opposing field. Nonparametric analyses of proportion of ball placements suggest no tactical bias for left-handed players when competing against right- and left-handers (backhand 60%, forehand 40%), respectively. However, for right-handed players a significant 3.2% difference in proportion of balls placed on the backhand side (58.3% right-handed and 55.1% left-handed opponents) was found, χ² (1, N = 15, 130) = 14.23, p < 0.01. The results indicate a tactical left-right bias in right-handers even at the highest level of professional tennis. Thus, the advantage of left-handers in interactive sports may be at least partially a consequence of players’ generalized hitting preferences to the right side. Has peak performance changed over time? An update of Schulz and Curnow (1988) Logan, Jane; Joseph Baker, York University In 1988, Schulz and Curnow presented data on the age at which peak performance occurs in sprint (e.g., track), endurance (e.g., marathon), and skill-based sports (e.g., golf, baseball). Twenty years have passed since this classic study was published, and in light of the current controversy surrounding performance-enhancing substances, it seemed pertinent to reexamine age of peak performance in the sports examined by Schulz and Curnow. Data from Olympic swimming, Olympic track and field, professional baseball, and professional golf were collected from official archives, from 1980 through to the present time. For the Olympic sports, the age and time of the gold medal winners in track and field and swimming events were collected from 1984 to 2004. For baseball, the top three performances in hitting and pitching statistics were collected, as well as the age of the athlete. The ages of the players of the year in PGA golf were also included in the sample. T-tests demonstrated that the peak for events requiring explosive power (e.g., high jump in men) has increased over the past twenty years (t = 2.66, p < 0.04), from early twenties to late twenties (e.g., 28 for long jump). As well, peaks for female athletes have aged as well (e.g., 100-m dash, t = 4.75, p < 0.005), from early twenties to late twenties; this increase may be explained by higher rates
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of participation in Olympic sports. However, the peak performance in the majority of events did not change. Implications of these findings will be discussed. The influence of team goal setting on cohesion and team performance Loughead, Todd M.; Krista J. Munroe-Chandler, University of Windsor It has been shown that higher levels of cohesion is related to improved performance (Carron, Colman, Wheeler, & Stevens, 2002). Given the significant relationship between cohesion and performance, it is not surprising that coaches make attempts to enhance cohesion. The process of developing or enhancing cohesion can be accomplished through a process known as team building. One common method of team building is goal setting (Widmeyer & Ducharme, 1997). Overall, the research suggests that team goal setting positively influences cohesion and individual goal setting positively influences performance. However, it is unknown how the different types of goals influence cohesion and team performance. Therefore, the purpose of the study was to examine the influence of assigned and participative team goal setting on cohesion and team performance. The participants were 201 undergraduate kinesiology students who completed a novel task in teams of three. Participants were randomly assigned to one of three team goal setting conditions: assigned, participative, or control. The results revealed a significant multivariate effect for team goal type, Pillai’s trace, F(10, 390) = 3.12, p < .05. Insofar as cohesion is concerned, post hoc ANOVAs revealed significant differences between participative team goal setting and the control condition on perceptions of social cohesion ATG-S and GI-S as measured by the GEQ. Specifically, the participants in the control condition perceived ATG-S and GI-S to a greater extent than participants in the participative team goal setting condition, F(2, 198) = 2.98, p < .05) and F(2, 198) = 5.48, p < .05, respectively. As for performance, participants in the assigned team goal setting condition significantly improved their performance more than their participative team goal setting counterparts, F(2, 198) = 5.39, p < .05. The results are discussed in terms of their implications for understanding the role of team goal setting in sport. The why and how of exercise goal pursuit: Self-determination and goal process cognition Lutz, Rafer; Baylor University; Paul Karoly, Morris A. Okun; Arizona State University There is ample evidence to suggest that self-determination for exercise predicts variance in exercise participation. It is less clear, however, what motivational strategies are employed by those who have more self-determined motivational profiles. Such an understanding may lead to better interventions to promote adherence to physical exercise regimens. Goal process cognition, thoughts about the goal striving process, organized within a control systems (Ford, 1987) framework exist as a possible means to assess motivational strategies and processes. The purpose of this research was to examine goal process cognition as a mediator of the relationship between the self-determination index and strenuous exercise participation. Surveys were administered to university students (N = 535) who were asked to identify their most important exercise goal and rate this goal according to nine goal process dimensions of the Goal Systems Assessment Battery (Karoly & Ruehlman, 1995). Students were also asked to complete measures of self-determination for exercise and leisure-time exercise participation (Leisure Time Exercise Questionnaire; Godin & Shephard, 1985). To examine mediation, a multiple mediator model was tested using the Preacher and Hayes
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(2007) bootstrapping procedure. There was a fully mediated effect of self-determination for exercise on strenuous leisure-time exercise. There was no direct effect of self-determination on strenuous exercise participation and 72% of its total effect on strenuous exercise was indirect via the goal processes of self-monitoring, planning, and positive arousal for exercise goals. Thus, it appears that goal process cognition is a viable means for understanding how self-determination influences strenuous exercise behavior. Also, future studies should further examine intervention strategies centered on self-monitoring and planning, as well as attempts to create greater positive arousal for exercise goals. The relationship between coaching efficacy, coaching experience, and leadership styles among coaches in Botswana Malete, Leapetswe; University of Botswana; Philip J. Sullivan, Brock University Much research has supported the construct of coaching efficacy and its various predictors, particularly coaching education and coaching experience. However, little is known about how these factors are related to leadership styles. Examining the impact of coaching efficacy and coaching experience on leadership styles of coaches should make significant contribution to the burgeoning literature on this less studied yet important construct. The current study examined the relationships between coaching efficacy, coaching experience, and leadership styles. One hundred and eighty-four coaches from Botswana completed the Coaching Efficacy Scale (Feltz et al., 1999) and the Revised Leadership Scale for Sports (Zhang et al., 1997). Given that the four factors of the CES were highly intercorrelated, a second-order factor of general coaching efficacy (GCE) was used in the subsequent analysis. Further, only the LSS factors of positive feedback, training and instruction, situational consideration and social support were significantly related to coaching experience and GCE. Four stepwise multiple regressions were run with each factor of the LSS as a dependent variable to determine the nature of the relationships between coaching efficacy, experience, and leadership style. Conceptual models of both coaching efficacy and coaching effectiveness state that experience affects efficacy, which in turn affects leadership style. Therefore, in each model coaching experience was entered as a predictor on the first step and GCE on the second. For each LSS factor, each stepwise regression was significant (p < .001). Further, the addition of efficacy as a predictor led to a significant improvement to each model (p < .001). Together, these two variables accounted for between 12 and 25% of the variance in coaching style. In each model, coaching efficacy resulted in an R2 change of approximately .10. Therefore, both coaching experience and coaching efficacy appear to be significant sources for a variety of leadership styles of coaches. Team building interventions in sport: A meta-analysis Martin, Luc J.; Albert V. Carron, Shauna M. Burke; University of Western Ontario Team building has been defined as “a method of helping the group to (a) increase effectiveness, (b) satisfy the needs of its members, or (c) improve work conditions” (Brawley & Paskevich, 1997, p. 13). The primary purpose of the present study was to conduct a metaanalysis of studies that have used team-building interventions in sport teams. A secondary purpose was to examine the influence of various moderator variables: source of publication (refereed, unpublished), study design (quasi-experimental, nonexperimental), method of delivery (indirect, direct), dependent variable examined (performance, cohesion), and type of intervention goal setting (adventure experience, omnibus). Standard literature searches produced 16 studies containing 166 effect sizes. The effect sizes were subjected to the
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corrections suggested by Hedges and Olkin (1985). Overall average Hedges’s g was .452 (p < .001). Subsequent analyses indicated (a) a small positive effect for published (g = .232, p < .004) and a moderate positive effect for unpublished (g = .624, p < .001) studies, (b) a small effect for studies with quasi-experimental designs (g = .223, p < .003) and a moderateto-large effect in nonexperimental studies (g = .638, p < .001), (c) moderate effects for both direct delivery (g = .460, p < .001) and indirect delivery interventions (g = .466 p < .001), (d) a moderate positive effect for performance (g = .634, p < .001), (e) small effects for individual attractions to the group-social (g = .265, p < .005) and group integration-social (g = .330, p < .001), (f) moderate-to-large effects for individual attractions to the grouptask (g = .520 p < .007) and group integration-task, respectively (g = .744, p < .001), (g) moderate-to-large effects for goal setting and adventure experiences interventions (g = .686 and .674 respectively, p < .001), and (h) no effect for omnibus interventions (g = .089, p > .05). The results are discussed in relation to their contribution to group dynamics theory and practice in sport. Exercising self-control: A lab-based measure of exercise-related self-regulatory strength predicts 8-week exercise adherence Martin Ginis, Kathleen A.; Steven R. Bray, McMaster University The limited strength model (Schmeichel & Baumeister, 2004) posits that self-regulatory strength is a finite, renewable resource that is drained when people attempt to regulate emotions, thoughts, or behaviors. Consequently, when a situation demands two consecutive acts of self-regulation, performance on the second act is frequently impaired. Self-regulatory depletion may explain people’s inability to follow through with their exercise intentions (Baumeister et al., 1994). As such, we hypothesized that a trait measure and an exercisespecific measure of self-regulatory strength would predict exercise adherence. Participants were 27 women (M age = 19.96) whose motivation to perform an impending exercise bout was assessed immediately before and after a cognitive self-regulatory depletion task. Changes in motivation were considered an index of exercise self-regulatory strength. They also completed the Self-Control Scale (Tangney et al., 2004) and indicated how many days/ week and min/session they intended to exercise over the next 8 weeks. Adherence was operationalized as the difference between the amount of exercise participants planned to do and the amount that they actually did over 8 weeks. Exercise self-regulatory strength significantly predicted adherence-days/wk, over Weeks 1 to 4 (r = .43) and Weeks 5 to 8 (r = .52, ps < .05); women who reported a greater decrease in motivation following the selfregulatory depletion manipulation also did fewer days of exercise than planned. Exercise self-regulatory strength did not predict adherence-min/session. Trait self-control did not predict adherence-days/wk or adherence-min/session (all ps > .07). In partial support of the limited strength model, our results indicate that women who are more susceptible to the acute effects of self-regulatory depletion on exercise motivation are more likely to skip planned exercise sessions. These findings have implications for understanding how daily self-regulatory demands can lead to episodes of exercise nonadherence. An investigation of the influence of self-modeling on causal attributions McCardle, Lindsay; Diane M. Ste-Marie, Rose Martini; University of Ottawa Dowrick (1999) proposed the method of feed-forward self-modeling (FF-SM) in which a video is edited to show a higher level of performance than the learner’s current ability. In this experiment, the FF-SM video showed a gymnast performing a combination of two floor
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skills which they were able to do separately but not yet in combination. Eight gymnasts (7 females, 1 male; M age = 9.9) participated in a pretest, nine intervention sessions, and a posttest. During the intervention sessions, the gymnasts received a FF-SM video for one skill combination and no intervention for a control skill combination. We investigated the possible influences of viewing the FF-SM video on the gymnasts’ self-regulatory processes within the context of Zimmerman’s (2000) model of self-regulation. We had a specific focus on the causal attribution process of the self-reflection phase. Weiner’s 1986 theory of causal attributions puts forward three important dimensions to individuals’ attributions: locus of causality, controllability, and stability. These were tested by having participants complete a modified Revised Causal Dimension Scale (McAuley, Duncan & Russell, 1992) for both the control and FF-SM skill combinations. First, they reflected on a well-performed skill combination. A repeated measures ANOVA revealed that there were no differences between the FF-SM and control combinations (F = 2.4, p > .05). There was, however, a significant main effect for dimension (F = 14.25, p < .001). In addition, participants reflected on a poorly performed combination for each FF-SM and control conditions. A repeated measures ANOVA was performed and again found significant differences as a function of dimension (F = 23.99, p < .001) but no main effect for FF-SM versus control conditions (F = 1.17, p > .05). Adolescent swimmers’ goals and stress appraisals across a swim season McDonough, Meghan H.; Purdue University; Valerie Hadd, Peter R.E. Crocker, University of British Columbia; Katherine A. Tamminen, Nicholas L. Holt; University of Alberta; University of Alberta Adolescent athletes experience considerable stress surrounding competition in sport. Lazarus’s (1991, 1999) cognitive-motivational-relational theory suggests that stress is dynamic, context-dependent, and influenced by goals and goals importance. Many previous studies have examined stress in sport using retrospective or cross-sectional designs. More recently there has been an emphasis on examining the stress process over time to better understand the patterns of stress appraisals and how they change and develop over time in competitive situations. Therefore, this study used a qualitative approach to document patterns of stress appraisals and links to their goals among elite adolescent swimmers across one season. Four female and four male swimmers who were participating in provincial and national level meets took part in the interviews. Four of the swimmers were in the 14 and under age category and four were 17 and under. Swimmers were interviewed nine times each: at the beginning of season and before and after each of four major meets. Data was analyzed first using a content analysis approach to identify the types of goals and stress appraisals experienced, and then using an interpretive phenomenological analysis (Smith & Osborn, 2003) to examine changes in goals and stress appraisals across the season. Swimmers identified several types of stress appraisals relating to swimming performance (e.g., pressure to improve time, technique, qualifying for future events, pressure to perform), interpersonal relationships (e.g., coach, friends/teammates, parents), and environmental (e.g., unfamiliar conditions) and physiological (e.g., fatigue, pain, injury/sickness) conditions. Stress appraisals that were linked to goals (e.g., pressure to improve time) exhibited some consistency between the pre- and post-race interviews and across the season for many swimmers. Findings have implications for future research examining the link between stress and coping attempts over time in athletic settings.
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Examining needs satisfaction in “action” stage exercisers McGowan, Erin L.; Erin Pearson, Craig Hall, Harry Prapavessis, Kim Shapcott, University of Western Ontario; Paul Gorczynski, University of Toronto; Courtney Newnham-Kanas, University of Western Ontario; Johan Wikman, University of Copenhagen The purpose of the study was to examine the relationship between perceived need satisfaction as conceptualized in self-determination theory (SDT; Deci & Ryan, 1985; 2002) and physical activity behavior over a six month period of time. Participants included “new exercisers” (N = 186; 81.2% female) between the ages of 18 and 50. At baseline (T1) participants completed demographic information as well as the Psychological Need Satisfaction in Exercise Scale (PNSE; Wilson, Rogers, Rodgers, & Wild, 2006) that measures competence, autonomy, and relatedness, and the International Physical Activity Questionnaire (IPAQ; Craig et al., 2003). The PNSE and the IPAQ were again completed by participants at 2 months (T2), 4 months (T3), and 6 months (T4). Path analysis results indicated that (a) competence, autonomy and relatedness remained stable over the four time points; (b) baseline competence and relatedness were both significantly related to physical activity behavior at T2, and T2 physical activity behavior was significantly related to T3 competence and relatedness; and (c) T2 physical activity behavior was significantly related to T3 autonomy. Overall, the results demonstrate that SDT appears to be useful for understanding the temporal pattern of physical activity behavior in “new exercisers.” Physical activity and successful aging in Canadian older adults Meisner, Brad A.; A. Jane Logan, York University; Ann-Marie Kungl, North SimcoeMuskoka Local Health Integration Network; Patricia Weir, University of Windsor; Joseph Baker, York University The number of older adults living in Canada will increase considerably over the next few decades. Alas, many older adults may experience conditions of morbidity and/or dependency. Consequently, gerontologists have focused on latent factors associated with optimal health with aging. Rowe and Kahn 1987 proposed that successful aging (SA) is the balance of three components: (a) absence of disease and disease-related disability; (b) high functional capacity; and, (c) active engagement with life. The main purpose of this study was to examine the Rowe and Kahn (1987) model criteria in older Canadian individuals to determine the role that physical activity (PA) has on the promotion of SA. A secondary objective was to identify potential demographic correlates associated with SA. An ordinal regression model was used to examine the relationship between PA and SA. Data from the Canadian Community Health Survey, cycle 2.1, were used (N = 12,042). Main results indicated that PA is a significant predictor of SA such that active respondents were more than two times as likely to be rated as SA. This effect was present after adjusting for significant demographic covariates. Furthermore, three demographic covariates reliably predicted SA: (a) younger respondents were more likely to be aging successfully than older respondents; (b) those with lower SES were less likely to be rated as successful compared to reports of greater SES; and, (c) males were more likely than females to be rated as aging successfully. Findings provide additional evidence regarding the role that PA plays in maintaining optimal health in later life. This main effect highlights the need for increased public health awareness, particularly for PA promotion. Also, at-risk groups were discovered that will aid when targeting prospective interventions. Implications of these findings in a clinical setting will be discussed.
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Exploring growth, maturation, and social physique anxiety in female athletes Monsma, Eva V.; Jennifer L. Gay, Toni Torres-McGehee; University of South Carolina This study examined the relationship between indicators of puberty and social physique anxiety (SPA) among female adolescent athletes. SPA, a salient predictor of eating disorders, tends to increase with age but little is known about underlying pubertal factors such as the growth spurt and menarcheal timing. Participants were adolescent female athletes, n = 362 (74.6% aesthetic) who completed the SPA scale (Martin et al., 1997), self-reported age at menarche, and underwent anthropometric measurements. Maturity offset (MO), a proxy estimate of peak height velocity (PHV), was derived (Mirwald et al., 2002). SPA was significantly correlated (p < 0.01) with MO (r = −0.29) and age at menarche (r = 0.18) but not with age. Aesthetic individual sport participants reported higher SPA scores than other sport types (aesthetic team, nonaesthetic individual, or nonaesthetic team) and attained menarche later (p = .001). SPA did not differ between pre- and postmenarcheal girls. Late maturers had higher SPA scores than early maturers who had the youngest age at PHV (M = 12.10, SD = 2.12). Late maturers had the oldest age at PHV (M = 14.03, SD = 1.49). Age accounted for 1% and sport type 8% (p = .001) of the variance in SPA. Separate hierarchical regression analyses indicated that MO explained 15% of SPA variance (p = .001), but age at menarche was not a significant predictor. Aesthetic individual sport participants were late maturers but reported higher SPA. Because leanness and linearity are associated with later maturation and certain sport contexts, these findings indicate that aesthetic sports may perpetuate negative self-perceptions through size-related mechanisms. MO predicted more variance in SPA than age, suggesting that SPA is associated with growth and maturation and is not just age-related. Given the association with maturational timing, the construct validity of MO is supported by these results. Subsequent investigations should consider critical growth periods in the etiology of maladaptive perceptions and perhaps behaviors. Transformational teaching and health promotion: A focus group study Morton, Katie L.; Sharon E. Keith, Mark R. Beauchamp; University of British Columbia The present study drew from Bass and Riggio’s (2006) full range model of leadership, to examine adolescent perceptions of the prevalence of, and preference for, transformational and transactional teaching behaviors within school-based physical education settings. Eight focus groups were conducted with 62 Canadian high school students (aged 13 to 15) and data were analyzed using a combination of deductive and inductive content analytic procedures. The results revealed that physical education teachers were primarily perceived by adolescents to employ transactional behaviors (i.e., management-by-exception, contingent reward) rather than transformational behaviors (i.e., idealized influence, inspirational motivation, individualized consideration and intellectual stimulation). However, adolescents also indicated a greater preference for teachers to employ transformational teaching behaviors within physical education settings. Issues related to theory development, future research, and the application of transformational teaching to physical activity and health promotion settings are considered. Implications for fostering physically active lifestyles amongst adolescents are also discussed. Transformational teaching and physical activity among adolescents: What is it and does it matter? Morton, Katie L.; Mark R. Beauchamp, University of British Columbia
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A potentially important framework, and one that has yet to be applied to the fields of health promotion, behavioral medicine, and indeed physical education, relates to the full range model of leadership developed by Bass and colleagues (Bass & Riggio, 2006). This model conceptualizes transformational and transactional leadership. The purposes of this study were twofold. Using a qualitative interview-based methodology, the first purpose of this study was to examine the extent to which transformational behaviors manifest themselves within school-based physical education settings. The second purpose was to examine the extent to which transformational teaching behaviors, as utilized by physical education teachers, were aligned with adaptive physical activity outcomes among adolescents. Semistructured interviews were conducted with 18 students (10 females, 8 males, M age = 14 years) and data were analyzed using a constructivist grounded theory approach (Strauss & Corbin, 1990). Results revealed that students who perceived their physical education teachers to utilize transformational behaviors (e.g., idealized influence) also described more adaptive responses, which were categorized as cognitive (e.g., self-efficacy to be physically active), affective (e.g., satisfaction with the teacher), or behavioral (e.g., effort in class) in nature. Directions for future research and theory development are addressed, along with implications that relate to the fostering of physically active lifestyles among children and adolescents. Sources of support for exercise: A self-determination perspective Muon, Sovoeun; Meghan E. LeBlanc, Philip M. Wilson; Brock University Previous research examining the relationship between exercise behavior and perceived support from others has typically focused on a restricted array of sources (Wilson & Rodgers, 2004; Edmunds et al., 2006). The purpose of this study was to identify and describe other relevant sources of perceived support for exercise as reported by young adults, using selfdetermination theory (SDT; Deci & Ryan, 2002) as a guiding framework. The sample in this study (N = 257; 62.7% female) were physically active (M METS = 52.88; SD = 29.30), healthy (M BMI = 23.48; SD = 3.05), and in young adulthood (M age = 20.83 years; SD = 2.20). Participants completed a series of open-ended questions prompting them to declare which individuals they perceived to be important to their exercise participation and experiences with respect to perceptions of autonomy support, structure, and involvement (Deci & Ryan). Preliminary analyses revealed that participants reported 76 different sources of autonomy support, 81 sources for structure, and 49 sources for involvement. Descriptive statistics indicated that 29.4% of participants reported 5 sources of autonomy support, whereas 16.9% and 13.3% of participants provided 5 sources for structure and involvement respectively. Among the diverse sources reported, the most frequently stated sources were friends (ranging from 17.2%–28.8%), fathers (6.4%–8.8%), and mothers (6.9%–13.4%). Overall, the results of this study extend previous SDT-based research by implicating multiple sources of perceived support for exercise participation that may be relevant to adherence decisions in young adults. Future studies may wish to be cognizant of the various sources of perceived support relevant to young adults engaged with regular exercise and consider using SDT as a guiding framework for understanding the manner in which various sources (as well as agents of support) influence adherence, maintenance, and termination decisions in young adults. Funding for this study was provided by SSHRC Lifting anxiety: Strength-training in a mixed-sex environment induces greater state social physique anxiety than in a same-sex environment Murru, Elisa C.; Kathleen A. Martin Ginis, Heather A. Strong; McMaster University
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Self-presentational concerns have been identified as a potential barrier to exercise participation requiring further study (Hausenblas, Brewer, & Van Raalte, 2004). Two aspects of self-presentation that have been studied in the context of exercise are situational social physique anxiety (SSPA) and self-presentational efficacy (SPE). Characteristics of the exercise environment have been found to influence both SSPA (e.g., Kruisselbrink, Dodge, Swanburg, & MacLeod, 2004) and SPE for exercise (e.g., Gammage, Martin Ginis, & Hall, 2004). One aspect of the exercise environment that has been found to influence SSPA and SPE among women is the presence of men (Kruisselbrink et al., Gammage et al.). However, it is not known how mixed- and same-sex exercise environments influence SSPA and SPE in the context of strength-training. Therefore, the purpose of the present study was to examine changes in SSPA and SPE among 47 sedentary women with little strength-training experience (M age = 21.70 years, SD = 3.45), who were randomly assigned to strength-train in either mixed-sex or women-only exercise environments. SSPA and SPE were measured immediately pre- and postparticipation in a 45-min beginner’s level group strength-training class. Repeated-measures ANOVAs revealed a significant Condition × Time interaction for SSPA, F(1, 45) = 15.36, p < .001, η2 = .25, indicating that women exercising in the same-sex environment experienced a significant decrease in SSPA, whereas women exercising in the mixed-sex environment had consistently high SSPA from pre- to postexercise class. Also, a main effect for time on SPE was found, F(1, 45) = 9.48, p < .01, η2 = .17. Participants in both conditions experienced significant increases in SPE of similar magnitude. Results of this study suggest that it may be beneficial for sedentary women who wish to start strength training to begin in a women-only environment in order to minimize social physique anxiety. A qualitative analysis of athletes’ voluntary image speed manipulation O, Jenny; Craig R. Hall, Samantha Pang, Krista J. Munroe-Chandler; University of Western Ontario It is common for sport psychology practitioners to suggest that imagery be performed at “real time” speed (e.g., Nideffer, 1985); however, several studies have anecdotally reported the use of slow and fast motion images by athletes (e.g., Munroe et al., 2000). In a recent quantitative analysis, O and Hall (2007) found that athletes reported employing not only real time, but also slow motion and fast motion image speeds for all imagery functions (Hall et al., 1998). O and Hall proposed that voluntary manipulation of image speed may serve a functional role for athletes. The primary purpose of the present study was to gather descriptive data regarding elite athletes’ voluntary use of image speed manipulation when imaging for sport. Sixteen varsity athletes (8 male, 8 female; team and individual sports) participated in semistructured interviews that focused on identifying the various functions that voluntary image speed manipulation serve for athletes. Content analysis of interview transcripts provided insight into the nature of athletes’ image speed manipulation in both practice and competition. Slow motion images were most often used by athletes in practice to focus on specific movements or sequences of novel or complex skills and strategies. Real time images were reported as being used most frequently overall, and used most often before competition to assist in accurately replicating the competition environment to increase feelings of familiarity and confidence. Fast motion images were used most often during competition to “fast forward” through sections of images that athletes deemed as unhelpful in strategy selection. Additional information was also gleaned concerning developmental changes in image speed use, the combination of image speed manipulation with other visual features of images, and
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the use of multiple image speeds in single imagery sessions. Results are discussed in terms of directions for future voluntary image speed research and applications. The relative age effect among female Brazilian youth volleyball players Okazaki, Fabio A.; Birgit Keller, Federal University of Parana; Fabio E. Fontana, Ovande Furtado; Eastern Illinois University The aim of this study was to examine the relative age effect among female youth volleyball players in Brazil. The relative age effect refers to performance disadvantages of children born early in the competition year compared to children born soon after the cutoff date. Only a few studies have concentrated in female youth sports, and they generally did not support the relative age effect (Helsen, Winckel, and Williams, 2005; Vincent & Glamser, 2006). For the current study, birth dates were acquired from the rosters of teams registered to play the female Under-14 2005-International Volleyball Cup held in Curitiba, Brazil. A total of 114 under-14 female players participated in the study of which 62 were born in 1991 and 52 in 1992. Three separate chi-square analyses were performed to examine the birth date distribution. An overall analysis combining years 1991 and 1992 was performed first. Results from this analysis were significant (M = 34.82, df = 3, p < .0005). More players were born in the first quarter than in any other quarter of the year. Similar results were achieved when the years 1991 and 1992 were considered separately. The results for 1991 (M = 14.26, df = 3, p = .003) and 1992 (M = 15.23, df = 3, p = .002) were also significant. This study indicates an overrepresentation of youth female players born in the early quarters of the competition year (Jan.– Dec.). Results may be due to the popularity of women’s volleyball in Brazil. In more popular sports, there is a larger competition for a spot in the team. Well-being indices: The association with health-enhancing physical activity Oster, Kristin G., Diane E. Mack, Katie E. Gunnell, Philip M. Wilson, Brock University; Peter R.E. Crocker, University of British Columbia; Kent C. Kowalski, University of Saskatchewan Physical activity has consistently demonstrated small, albeit meaningful, relationships with indices of psychological well-being (Biddle, Fox, & Boutcher, 2000). The present investigation extended existing literature by operationalizing well-being as purposeful engagement in life (i.e., eudaimonic well-being; Waterman, 1993). More specifically, the pattern of relationships between indices of eudaimonic well-being, the satisfaction of basic psychological needs, and engagement in health-enhancing physical activity HEPA were examined. A convenience sample of university students (N = 168; n [females] = 106) volunteered to participate. On a single occasion, participants completed an Internet-based questionnaire comprised of three instruments: the Scales of Psychological Well-being (Ryff & Keyes, 1995), which assesses six dimensions linked to eudaimonic well-being; the Psychological Need Satisfaction in Exercise (PNSE; Wilson, Rogers, Rodgers, & Wild, 2006) and; the Short Questionnaire to Assess Health-Enhancing Physical Activity (Wendel-Vos & Schuit, 2002). Bivariate correlations revealed moderate-to-strong relationships across dimensions of eudaimonic well-being (rs = .42–.80). Consistent with suppositions advocated by Ryan, Huta, and Deci (in press), positive relationships between eudaimonic well-being and PNSE scores were noted rs = .25–.37. The pattern of relationships between eudaimonic well-being and HEPA (rs = −.04–.13) was somewhat inconsistent with Ryff and Singer (in press), who
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suggested that eudaimonic well-being may be positively associated with active engagement in health behaviors. Based on this preliminary investigation, theoretical predictions between eudaimonic well-being and psychological need satisfaction were supported. The link between eudaimonic well-being and HEPA warrants continued exploration. This research was supported by the Social Sciences and Humanities Research Council of Canada. The athlete-parent-coach triad: Perceptions of coaching competence and coaching efficacy in youth sport Paiement, Craig A.; Ryan Hedstrom, William Porecca; Castleton State College In youth athletics, a coach plays a variety of roles, such as teacher or role model. The interplay between positive adult role models, nonparent adult relationships (i.e., coach), and youth programs (i.e., organized sports) have been found to greatly influence the “developmental assets” that a young person acquires. Within the current youth sport structure, there is interplay among parents of young athletes, the athletes, and coaches. Hellstedt (1987) refers to this phenomenon as the athlete-parent-coach triad. The relationship between athlete, parent, and coach can be one of strength or strain on a child’s sport involvement. Understanding this triangulation can allow coaches, parents, and athletes to maximize the experience of sport involvement. The purpose of this research is to examine the athlete-parent-coach triad by investigating coaches’ level of efficacy and how it relates to athletes and parents’ perceptions of coaching competency. Participants include 275 youth athletes, parents, and coaches from 19 teams. The coaching competency scale (CCS; Myers, et al., 2006), a 24-item scale that measures athletes and parents’ perceptions of their coach’s competency was used for this study. This measure is analogous to the coaching efficacy scale (CES; Feltz et al., 1999) used with the coaches. A factorial MANOVA was conducted to assess the differences in parent and athlete perceptions and coaches’ efficacy. Results indicate that parents, athletes and coaches differ in perceptions, Wilks’s Λ = .881, F(10, 462) = 2.71, p = .03, of competency and efficacy, and these perceptions also differ by team, Wilks’s Λ = .475, F(90, 1,014)= 1.89, p < .001), although the effect sizes were small. Scheffe post hoc results indicate that coaches rate their efficacy significantly higher than the perceptions of athletes and parents and significantly lower than perceptions of parents in game strategy. Only one team indicated difference in all areas. The lack of difference between groups’ perceptions can lead to positive support relationships from parents and athletes, an important factor for coaches. Social support and exercise in cardiac patients: Does it really help? Pelaez, Sandra; Concordia University; Kim L. Lavoie, Université de Quebec a Montreal; Andre Arsenault, Montreal Heart Institute; Simon L. Bacon, Concordia University Background and goal: Coronary heart disease (CHD) is one of the leading causes of death in the Western world. The benefits of exercise (EX) in these patients are widely known; however, it has been well documented that these CHD patients fail to either initiate or maintain EX programs. Social support (SS) has been shown to influence EX adherence. The aim of this study was to investigate the role of SS on EX in patients with CHD. Method: 758 cardiac outpatients (236 women, 520 men) referred for an exercise stress test at a tertiary care cardiac center were recruited. All patients completed sociodemographic, anthropometric, and EX questionnaires. Results: After controlling for age, sex, and peak exercise METS, living with someone—irrespective of the relationship—was related to EX, F = 5.41, p = .020, such that those individuals who lived with someone (28.17 % of the population) tended to
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exercise less than people who did not live with anyone (71.83 %). With regards to different sources of SS, living with a partner (F = 0.37, p = .544), living with a parent (F = 1.78, p = .182), living with a friend (F = 0.00, p = .984), and living with anyone else (F = 0.00, p = .944) was not significant related to EX. The only source of SS related to EX participation was living with children (F = 8.24, p = .004). Living with children was significantly related to a lack of EX in the patients of this sample. Further analyses were run to assess the interaction between living with children and cohabitation and living with children and sex. Results indicated that there were no interactions (F = 0.00, p = .970, and F = 1.30, p = .255, respectively). Irrespective of sex and cohabitation, having children resulted in a reduction of EX. Discussion: This pattern suggests that interventions to promote adoption, maintenance, commitment, and adherence to EX involvement in cardiac patients should probably target the whole family in order to attain better results regarding EX adherence. Future research is needed to investigate the dynamic underlying the present relationship. FQRSC Doctoral Research Fellowship #122942. Accuracy of free throw shooting during dual-task performance: Implications of attentional disruption on performance Price, Jayme L.; Diane Gill, Jennifer Etnier, Kurt Kornatz; University of North Carolina at Greensboro The division of attention among multiple demands has been studied in psychology for many years. Researchers in sport psychology have begun to map out the time course of attentional demands in athletic skills ranging from horseshoe pitching to sprinting, finding that particular points of a task pose a greater demand for attention than others. The purpose of this research was to use a dual-task paradigm to determine the point of peak attentional demand during the free throw shooting process. Thirty men (n = 26) and women (n = 4), ranging in age from 18 to 62 (M = 23.9 + 8.3 years), with at least two years high school basketball experience, comprised the sample. After baseline measures, each subject completed 40 free throw trials. During the free throw, the participant was instructed to respond verbally to a sound stimulus to determine reaction time (RT). The sound stimulus was administered at one of 4 probe position (PP) conditions or was not administered catch trial condition. The participant was blinded to the randomly ordered presentation of conditions. No significant difference in free throw performance as a function of PP was found (p > .05), suggesting that any differences in RT across conditions could be attributed to differences in attentional demand. Repeated measures analysis revealed significant differences in RT as a function of PP. Simple contrasts showed that RT at PP1 and PP2 was significantly slower (p < .05) than baseline RT, whereas PP3 and PP4 did not produce RTs significantly different (p > .05) from baseline RT. These results suggest that the pre-shot routine PP1 requires the greatest attentional demand, followed by the first upward motion of the ball PP2, and that later stages PP3, remaining upward motion of the ball, and PP4, immediately after ball leaves fingertips, create little attentional demand. Results lead to the implication that focusing strategies utilized during the pre-shot routine and the first upward motion of the ball may be beneficial to successful performance. Peer leadership in sport: Relationships among personal characteristics, leadership behaviors, and team outcomes Price, Melissa; Maureen Weiss, University of Minnesota
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The purpose of the present study was to extend previous research (Glenn & Horn, 1993; Moran & Weiss, 2006) by examining relationships among personal characteristics, peer leadership behaviors, and team outcomes. Adolescent female soccer players (N = 191) completed measures of perceived competence, peer acceptance, behavioral conduct, and intrinsic motivation; teammate ratings (Glenn & Horn, 1993) and self-ratings of leadership (Glenn, 2003); and team cohesion and collective efficacy. Because the peer leadership measures were new, factor analyses were conducted. The teammate-rated measure produced two factors—instrumental behaviors (confident, consistent, determined, skilled, respected) and prosocial behaviors (honest, responsible, positive, organized). Factor analysis of the self-rated measure produced a one-factor solution—effective peer leadership. Factor scores were created and used in canonical correlation analyses: (a) relationship between personal characteristics and peer leadership, and (b) relationship between peer leadership and team outcomes. The first analysis revealed a significant relationship (Rc1 = .62, Rc2 = .38, redundancy = 18.5%). Athletes who were rated higher by teammates on instrumental leadership and rated themselves higher in leadership behavior reported higher soccer competence, peer acceptance, and intrinsic motivation. Athletes rated higher on prosocial leadership by teammates scored higher on perceived behavioral conduct. The second analysis showed a significant relationship (Rc1 = .56, Rc2 = .18, redundancy = 15.8%). Athletes who rated themselves higher in leadership behavior reported greater task and social cohesion and collective efficacy. Athletes who were rated higher by teammates on instrumental and prosocial leadership reported greater social cohesion. Collectively, findings extend previous research by providing further validity for self- and teammate-rated leadership behaviors, and by demonstrating relationships among positive personal characteristics, effective peer leadership, and positive team outcomes. Prospective examination of physical activity and gestational weight gain in pregnancy Rauff, Erica; Danielle A. Symons Downs, Jennifer M. DiNallo; Pennsylvania State University High gestational weight gain (GWG) is associated with negative maternal and fetal outcomes. Meeting exercise guidelines in pregnancy may help women to mitigate their GWG; however, limited research has examined the possible protective effects of exercise during each pregnancy trimester. Purpose: To prospectively assess exercise behavior and GWG across the pregnancy trimesters. We hypothesized that (1) exercise behavior and mean GWG would be inversely associated, and (2) across each trimester women meeting exercise guidelines would have lower mean GWG than women who were less active. Method: Pregnant women (N = 316; M age = 30 years) prospectively self-reported their exercise behavior and GWG across the pregnancy trimesters. Women were classified as meeting or not meeting exercise guidelines based on the ACSM 2000 guidelines of 150 min of exercise/wk. Groups were first compared on pre-pregnancy BMI and no significant differences were found; thus, it was not entered as a covariate in the analyses. Results: Pearson correlations revealed that exercise and mean GWG in Trimester 3 were significantly inversely associated (ps < .05); however, these associations were not observed in Trimesters 1 and 2. One-way ANOVAs found no significant differences in GWG between women who met and did not meet exercise guidelines in Trimesters 1 and 2. However, in Trimester 3, women who met exercise guidelines gained significantly less weight (M = 8.9 lbs, SD = 5.2) compared to women who did not meet exercise guidelines (M = 12.9 lbs, SD = 4.2; F(1, 86 = 13.87, p < .05). Conclusions:
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During pregnancy Trimester 3, regardless of prepregnancy BMI, women who met exercise guidelines gained significantly less weight. These results suggest that meeting the current exercise recommendations may be a useful tool in preventing high weight gain, particularly in Trimester 3. Prenatal exercise interventions targeting the unique physical changes of each pregnancy trimester are warranted and may help to control GWG. Effects of green tea extract on cognition, mood, workload, physiology, and athletic performance Reed, Alex; Bryan Raudenbush, Wheeling Jesuit University Previous anecdotal reports indicate that green tea extract can have beneficial effects on overall health, cognitive functioning, and athletic performance. The purpose of the present study was to determine whether green tea extract could significantly impact cognitive functioning, endurance, perceived workload, mood, and physiology over time in a controlled experimental environment. The participants were 18 athletes who were tested over a 6-week time period. In a participant-blind administration, athletes consumed one capsule each day of the 6-week period that may or may not have contained green tea extract (experimental condition vs. placebo control condition). To assess cognitive functioning, athletes completed a variety of computer-based physiological and neuropsychological tests assessing word discrimination, verbal memory, design memory, attention span, reaction time, problem solving, and response variability. In addition, physical endurance was evaluated via a modified treadmill stress test (Bruce protocol) and performing pushups to exhaustion. Perceived workload was measured by the NASA-Task Load Index, and mood was assessed using the Profile of Mood States. Results of the experiment revealed athletes showed a significant improvement in the number of push-ups completed when given green tea extract. No statistically significant improvements were found for cognition or a positive mood; however, the majority of these measures were greater in the green tea condition. The implication of these results is that natural, and in the case of green tea, very healthy, substances could be used to enhance exercise-related endurance, rather than pharmacological methods such as caffeine and steroids. EEG coherence associated with using an explicit strategy during a motor task Rietschel, Jeremy C.; Brad R. King, Melissa M. Pangelinan, Jane E. Clark, Brad D. Hatfield; University of Maryland–College Park During motor skill acquisition, those given explicit instructions about a task demonstrate enhanced performance compared to those who are prevented from engaging explicit strategies. Recently, the electroencephalographic metric of coherence (specifically between the verbal-analytical region (T3) and motor-planning region (Fz)) has been used to index the degree of explicit, cognitive processes guiding movement. The purpose of this study was to investigate the relationship of T3-Fz coherence between those provided with an explicit strategy (ES), compared to those provided no explicit strategy (NES), during execution of a novel visuo-motor task. The task consisted of 150 trials of a 30° visual-feedback distortion causing a discrepancy with actual movement. The ES group was told about the rotation and how to compensate for it, whereas the NES group was not provided with this information. Coherence and initial directional error (IDE, indicative of performance) were calculated for the beginning (1–30 trials) and end of the task (120–150) and separately subjected to a 2 (strategy) × 2 (time) ANOVA with time as a repeated-measures variable. An interaction was revealed for coherence, F(1, 13) = 13.629, p = .003. Post hoc analysis revealed that the ES
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group had higher coherence than the NES group during the end of the task. As predicted, the ES group demonstrated better performance than the NES group regardless of time, p = .015. Further, the ES group developed increased cortico-cortical communication between task-relevant areas (T3-Fz coherence) as a result of being given an explicit strategy. This suggests adoption of this strategy over time. Future analysis will further investigate the relationship between T3-Fz coherence and motor performance. The athlete to coach transition: Does a new coach teach old tricks? Rotteau, Thea O.; James Lyons, McMaster University Evidence suggests that coach development begins during athletic participation (Erickson et al., 2007). Thus, novice coaches with previous playing experience should be more advanced in their development relative to those without such a background. However, others have found that expert performers have difficulty understanding the challenges associated with learning basic skills within their domain of expertise (e.g., Hinds, 1999). This study explored the effects of previous athletic experience on current coaching abilities in novice and experienced coaches. Twenty-three elite level gymnastics coaches were divided into four subgroups based on their coaching and athletic history. The coaches performed both a knowledgebase test asked to list technical errors associated with nine gymnastic elements, and an error detection task in which they watched a series of gymnastic video clips and were asked if and where a technical error occurred during the performance. Overall, experienced coaches demonstrated both a superior knowledgebase (F = 6.18, p < 0.03) as well as a greater sensitivity in detecting the presence of errors d’ = 1.066 vs. d’ = 0.788. Further analysis of the error detection task revealed a significant main effect for coaching experience (F = 22.7, p < 0.0002) as well as an Athletic Experience × Coaching Experience interaction (F = 5.3, p < 0.033). As expected, experienced coaches outperformed novice coaches. However, for the novice coaches the participants without previous athletic experience were better at identifying errors than those with previous athletic experience. These results suggest that although previous domain specific experiences do not affect a coach’s knowledgebase, there appears to be some degree of negative transfer between performing gymnastic elements and error detection within those elements. Further, these results suggest that rather than serving as a strong foundation for future coaching efforts, previous participation within the domain may in fact hinder coaching development. Promoting autonomous physical activity through autonomy need satisfaction following a group-mediated cardiac rehabilitation intervention. Russell, Kelly L.; Steven R. Bray, McMaster University Despite the known benefits of regular physical activity (PA) for cardiac patients, long-term adherence rates remain low following graduation from cardiac rehabilitation (CR) programs (Oldridge, 1991). Self-determination theory (Deci & Ryan, 1985) considers how the social environment can promote behavior through the nurturing of three psychological needs: competence, autonomy, and relatedness. Needs satisfaction is enhanced when individuals interact in social contexts that provide opportunities for mastery experience, positive feedback, and a chance to feel connected with others (Ryan & Deci, 2000). Individuals participating in CR would likely benefit from an environment that provides support for competence, autonomy and relatedness. The present study examined the effects of a 6-week group-mediated intervention promoting practice of self-regulatory skills on needs
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satisfaction and PA behavior compared with an exercise-only condition. It was hypothesized that autonomy and competence needs satisfaction during the intervention would mediate the effects of the intervention on postintervention PA behavior. Fifty-one volunteer graduates from a hospital-based CR program (M age = 66; 90% male) were randomly assigned to either a group-mediated intervention program (GMCB) (n = 25) or an exercise-only group (n = 26). Participants completed the PNSE (Wilson et al., 2006) at the start and completion of the program, and PA was assessed 6 weeks post-program using a 7-day PAR (Blair et al., 1985). The intervention group reported higher autonomy need satisfaction and postprogram PA compared with the exercise-only group (β = .38, p < .01 and β = .35, p = .01, respectively). After controlling for the effect of autonomy satisfaction, the intervention effect on PA was nonsignificant (p = .10) and reduced by approximately 30% (from β = .35 to β = .23), indicating partial mediation. Findings provide evidence of the behavioral benefits of participating in a group-mediated counseling program and the role that psychological need satisfaction can play in facilitating PA behavior among cardiac patients. Participation in school athletic teams and use of alcohol, tobacco, and cannabis among 10th graders: United States, 2006 Santiago, Olga J.; Carlos F. Rios-Bedoya, Deborah L. Feltz; Michigan State University Analyzing epidemiological data from the 2006 Monitoring the Future (MTF) survey, we evaluated a hypothesized negative association between participation in school athletic teams and use of alcohol, tobacco, and cannabis. The MTF survey assessed a national probability sample of 8th and 10th graders attending public and private schools in the United States (n = 5,612). The 10th-grader sample used in this study consisted of 2,786 students. The key response variables in this study are odds ratios for ever having used alcohol, tobacco, and cannabis (OR_a, OR_t, OR_c). The extent of sport participation was dichotomized in the low extent (LE) group (i.e., moderate, slight, or no involvement) and high extent (HE) group (i.e., considerable or great involvement). Results revealed that the estimated crude OR_a, OR_t, and OR_c from a logistic regression model for the HE group compared to the LE group were 1.3 (p < 0.001), 0.8 (p < 0.05), and 0.8 (p < 0.005). ). Statistical adjustments for sex, race/ethnicity, mother’s education, father’s education, and school grades produced no attenuation on the OR_a estimate (1.5; p < 0.001). The HE group had a 50% higher likelihood of ever using alcohol than the LE group. But the negative association found for tobacco and cannabis was no longer present (p > 0.05). Researchers and youth sport advocates suggested that sport participation could prevent or delay substance use. However, data from MTF survey do not support this hypothesis. On the contrary, HE participation tends to increase the likelihood of ever using alcohol among 10th graders. Further studies are needed to confirm or reject our findings because of their prevention implications. Relationship between passion, perfectionism, and general life satisfaction Schiphof, Lieke; University of Paris Sud–Orsay; Philippe C. Brunel, University of Limoges Vallerand et al. (2003) proposed a motivational approach of the passion individuals develop towards activities. This concept is based in part on SDT. Authors proposed a dualistic model in which they define passion as a strong inclination toward an activity that individuals like, that they find important, in which they invest time and energy, and which comes to be internalized in one’s identity. Obsessive passion (OP) results from a controlled internalization of
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the activity into one’s identity. Individuals feel compelled to engage in it owing to internal contingencies that come to control them. Harmonious passion (HP), by contrast, results from an autonomous internalization of the activity into the person’s identity and individuals fell free to engage in. Studies found a positive relation between HP and flow or positive affect experienced during task engagement, wheras OP was positively related to negative affect and rumination after engagement and when prevented from engaging in the activity altogether. The purpose of this study was to test the dualistic model. Participants (M = 22.56; SD = 1.55; N = 108, 42 males, 66 females) were requested to fill out the passion scale, the multidimensional perfectionism scale, the global motivation scale, perceptions of autonomy and competence and general life satisfaction. Results of partial correlation indicated that HP was positively linked to perceived autonomy (r = .31, p < .02) and consequently with the self-determined form of motivation (r = .25, p < .01), whereas OP was linked to the non-self-determined one (r = .29, p < .003). However, no relationship emerged between both types of passion and perceived competence. Furthermore, OP appeared positively linked to self-referenced perfectionism (r = .25, p < .01) and socially prescribed perfectionism (r = 35, p < .001). Finally, HP was positively related to life satisfaction (r = .41, p < .001), whereas OP was negatively linked to life satisfaction (r = −.21, p < .03). Results confirm the dualistic model and it appears that the more perfectionist individuals are the more obsessively passionate they are. Does relative frequency of augmented knowledge of results influence perceptual learning and retention in a handball task? Schorer, Jörg R., WWU Münster; Rouwen Canal-Bruland, University of Münster In motor learning, the role of frequency of augmented feedback is a well-studied subject. However, to date, the influence of frequency of augmented feedback on learning and longterm retention using video-based perceptual training has not been examined. The current study examined the influence of four frequencies of augmented feedback on perceptual learning and retention of an acquired anticipation task in a handball. The 48 novice goalkeepers were divided randomly into four groups of twelve participants. These included groups with augmented feedback in 0%, 33%, 66%, or 100% of the cases. A temporal occlusion approach with three different occlusion conditions was administered. Participants had to decide in which of four corners of a handball goal throws from four expert penalty shooters would go. Video stimuli were presented on a notebook with Presentation 9.81, and reactions were measured by keyboard presses, which were chosen in accordance with the different corners of the goal. As expected, results revealed differences between the three temporal occlusion conditions, F(1.45, 53.78) = 309.90; p < .01; η2 = .89. Additionally, a significant interaction was found for temporal occlusion and test phase, F(4, 148 = 5.71); p < .01; η2 = .13. Even after a 7-month retention interval, participants showed better performances than in pretest conditions, F(2, 74 = 10.77); p < .01; η2 = .22. However, results revealed no significant interaction between feedback conditions and tests, F(6, 74 = 0.75); p = .62. These findings suggest that concurrent visual feedback seems more important than augmented feedback in perceptual learning. To test this assumption, further studies using spatial and temporal occlusion paradigms are proposed. Goal striving and well-being in sport: An investigation of marathon runners’ responses to success and failure. Smith, Alison L.; Nikos Ntoumanis, University of Birmingham
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Grounded in self-determination theory (Deci & Ryan, 1985), the present study examined the impact of motives underlying runners’ target times upon tendencies towards self-aggrandizement and self-derogation following a marathon. Consequences of these tendencies for psychological well-being were also investigated. Target times were recorded for 193 British runners one week prior to a marathon along with self-report measures of motives underlying their target and psychological well-being (positive and negative affect). Follow-up well-being measures were completed in the week following the marathon. In addition, runners who attained their time (N = 74) completed measures of comparative (CSA) and noncomparative self-aggrandizement (NCSA), whereas those who did not (N = 119) completed a measure of self-derogation. Structural equation modeling supported a model—scaled χ2(17) = 22.94., p > .05, CFI = .95, NNFI = .92, RMSEA = .07 (CI = .00–.13), SRMR = .10—in which autonomous motives predicted both CSA and NCSA. Controlled motives were found to only predict CSA. In turn, NCSA was positively associated with changes in positive affect whereas CSA was positively associated with changes in negative affect. Additionally, autonomous and controlled motives were found to have positive and negative direct paths to premarathon positive affect, respectively. For those who did not attain their target time, structural equation modeling revealed—scaled χ2(13) = 19.66, p > .05, CFI = .94, NNFI = .91, RMSEA = .07 (CI = .00–.12), SRMR = .06—that controlled goal motives were linked to self-derogation, which in turn positively and negatively predicted changes in negative and positive affect, respectively. Autonomous motives were positively associated with premarathon positive affect alone. The findings support links between the motives underlying marathon runners’ target times and their responses following success and failure, and highlight implications for well-being. These findings are discussed in relation to implications for runners and future research directions. Season-long goal striving in sport: An investigation of the temporal interplay between goal motives, coping strategies, and well-being Smith, Alison L.; Nikos Ntoumanis, Joan L. Duda, University of Birmingham; Maarten Vansteenkiste, Ghent University Using a cross-sectional design, Smith, Ntoumanis, and Duda (2007) supported the selfconcordance model (Sheldon & Elliot, 1999) as a framework for further goal setting research in sport. Expanding upon these findings, the present study examined the goal motives underlying season-long goal striving in sport as well as the role of coping strategies in the goal striving process. Self-report measures of goal motives, effort, and goal attainment (Smith et al., 2007), in addition to measures of goal-related coping strategies, psychological need satisfaction, and psychological well-being (positive affect and life satisfaction), were administered to 97 British athletes at three time-points (start, mid-, and end of season) during a University sport season. Structural equation modeling supported a model—scaled χ2 (26) = 27.42, p > .05, CFI = .99, NNFI = .99, RMSEA = .02 (CI = .00–.08), SRMR = .11—in which autonomous goal motives at the start of the season linked to goal striving during the season through the following sequence: autonomous motives → mid-season effort → end of season attainment → changes in need satisfaction → changes in well-being. Changes in need satisfaction were additionally predicted by the interaction of autonomous motives and goal attainment. Controlled goal motives were found to be unrelated to goal striving. An additional structural model—scaled χ2 (53) = 58.55, p > .05, CFI = .97, NNFI = .96, RMSEA = .03 (CI = .00–.08), SRMR = .11—identified opposing associations of autonomous and controlled goal motives with mid-season effort, via approach and avoidance coping
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strategies utilized up to mid-season, respectively. The findings provide further support for the adaptation of the self-concordance model to context-specific goal striving in sport as well as demonstrating the differential roles of approach and avoidance coping strategies for goal persistence. These findings will be discussed in relation to the implications for athletes and directions for further research. Relationship between adolescent exercise identity scale scores and self-reported rates of physical activity Soukup, Gregory J.; Linwood B. Clayton, Ferrum College Anderson and colleagues have suggested that higher exercise identity is positively related to higher rates of physical activity in adults (1995, 1998, 2001). The purpose of this study was to determine if a significant relationship existed among high school adolescents regarding rates of exercise identity and physical activity. It was hypothesized that adolescent students with stronger rates of exercise identity would have higher rates of physical activity. Data were collected from a convenience sample of 310 students (164 females and 146 males) with an average age of 17 years and 4 months. Permission for the study was obtained from the university and school district where data were collected. Student assent and parental consent forms were obtained from all participants before data collection. The Exercise Identity Scale (EIS; Anderson & Cychosz, 1994) was used to estimate rates of exercise identity. The EIS has nine items rated on a 7-point Likert format. Responses range from strongly disagree (1) to strongly agree (7). Scores on the EIS range from 9 to 63. Higher scores indicate greater exercise identity. The Previous Day Physical Activity Recall (PDPAR; Weston, Petosa, & Pate, 1997), a self-report instrument, was used to determine rates of physical activity. A regression was executed to determine if a significant relationship existed between adolescent rates of exercise identity and physical activity. EIS scores were used as the independent variable and PDPAR rates were used as the dependent variable. Regression analysis of the data generated an r value of .366, which indicates a significant positive relationship between higher rates of exercise identity and higher rates of physical activity among adolescent participants. The R2 indicated that EIS scores explained 13.4% of the variance of the PDPAR rates. Results of the study indicate the EIS could be used as a tool by physical education, health, and exercise professionals to predict future rates of physical activity for adolescent students and clients. Social physique anxiety in pre-adolescents Stadulis, Robert E.; Kent State University; Mary J. MacCracken, University of Akron One of the important components of an individual’s self perception is how satisfied one feels about her/his body or physique and whether society’s emphasis on a person’s shape can lead to increased anxiety. To this end, Hart, Leary, & Rejeski (1989) developed the Social Physique Anxiety Scale (SPAS). Recently, Fender-Scarr et al. (2003) adapted Martin, Rejeski, Leary, McAuley, & Bane’s 1997 revised 9-item SPAS to a form that is appropriate to children (the SPAS-C). Stadulis et al. (2005) have reported adequate reliability and validity for the SPAS-C. The focus of the present investigation is to determine if and how social physique anxiety changes in preadolescence. Is there evidence that as a child advances in age anxiety concerning one’s body increases? At present, there appears to be little data that describes how social physique anxiety might change over age. A related question concerns the sex of the child: are boys and girls influenced differently such that their social physique anxiety
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responses are different? The SPAS-C was administered to preadolescent girls and boys (N = 319) between the ages of 9 and 14 years old. Cronbach alpha internal reliability = .791. Factor analysis yielded results matching a number of previous outcomes using adult data (Stadulis et al., 2007). Therefore, the reliability and validity of the SPAS-C with the current sample was supported. A two-factor ANOVA (Age × Sex) indicated significant (p < .05) effects due to both age and sex. The younger children, 9 and 10, evidenced the lowest levels of anxiety (M = 20.8), with the highest levels (M = 24.5) evidenced by the older children, 13 and 14. Females evidenced an earlier rise in anxiety, reaching the highest levels by 12 years of age and then remaining fairly stable through age 14. The boys reached approximately the same level of anxiety as the girls but not until age 14. These descriptive findings suggest that both boys and girls experience heightened social physique anxiety but that girls evidence an increase in anxiety at an earlier age. Are we having fun yet? Testing the effects of imagery use on affective states and enjoyment during and after moderate exercise Stanley, Damian M.; Jennifer Cumming, University of Birmingham Although many people start exercising for health reasons, the more intrinsic reasons of well-being and enjoyment typically predict higher levels of exercise behavior and adherence (e.g., Salmon, Owen, Crawford, Bauman, & Sallis, 2003). Such findings suggest the importance of identifying strategies to maximize people’s enjoyment of, and affective responses to, exercise. The current study compared the effects of different audio imagery scripts on exercise-related enjoyment and affect during and following an acute bout of 20 min of moderate intensity cycle ergometry (50% heart rate reserve). Physically active participants (n = 72) were randomly assigned to one of four experimental conditions: (a) enjoyment imagery; (b) energy imagery; (c) technique imagery; or (d) exercise only (control). It was hypothesized that the enjoyment and energy imagery groups would demonstrate greater enjoyment and larger improvements in affect than the control group. The interest/enjoyment subscale of the Intrinsic Motivation Inventory (Ryan, 1982) measured exercise-related enjoyment before and after the bout, and the Feeling Scale (FS; Hardy & Rejeski, 1989) and Felt Arousal Scale (FAS; Svebak & Murgatroyd, 1985) both measured exercise-related affect. A single-item 7-point scale was developed for this study to measure exercise-related enjoyment at Minutes 6, 12, and 18 of the bout. Repeated measures mixed analyses showed that the enjoyment and energy imagery groups reported enjoying the exercise bout significantly more than the control group at 5 min postexercise. The energy imagery group also reported a significant improvement in affect (both FS and FAS) from pre- to postexercise. One-way betweensubjects analyses revealed that the enjoyment imagery group reported significantly higher enjoyment than the control group at Minutes 12 (p = .02) and 18 (p = .00) during the exercise bout. These findings highlight imagery, in particular enjoyment and energy imagery, to be a psychological strategy that influences exercise-related cognitions. When the referee sees red . . . Strauss, Bernd; Norbert Hagemann, Jan Leißing; University of Münster Hill and Barton (2005) have shown that wearing red sports attire impacts positively on the outcome of single-combat sports. They suggest that it enhances performance in contests by triggering a psychological effect in the wearer (or in the opponent) reflecting an evolutionary association of the color red with dominance and aggression. We disagree
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with this interpretation, because the effect of red on performance and on the decisions of referees may well have been confounded in the original data. We propose alternatively that the perception of colors triggers a psychological effect in referees that can lead to bias in evaluating an identical performance. We conducted an experiment on the effect of the color of the protective gear in tae kwon do on the decisions of referees. A total of N = 42 experienced referees (13 female, 29 male; age: M = 29.30 years; experience as referees: M = 8.02 years) watched 22 videotaped excerpts from sparring rounds (2 balanced blocks of 11 clips in random order with an average length of 3.3 s). They had to decide how many points they would award either the red or the blue competitor. The color of the protective body gear was switched in both blocks using a digital toolkit. The main findings were that the competitor wearing red protective gear was awarded an average of 13% (1.88 points) more points, t(41) = 2.85, p < 0.01, d = .35, than the blue competitor. The number of points awarded increased when a blue competitor was digitally transformed into a red competitor (t(41) = 2.45, p < 0.01, one-tailed, d = .36) and decreased when a red competitor was digitally transformed into a blue competitor (t (41) = 1.66, p < 0.05, one-tailed, d = .25). Hence, competitors dressed in red are awarded more points than competitors dressed in blue despite identical performance. The effect found here can also explain the stronger influence of color in relatively symmetric contests. We argue contrary to Hill and Barton (2005) that it is the referee who is mainly responsible for the bias. What not to wear: Revealing exercise attire and public exercise settings increase women’s acute body image concerns and cortisol levels Strong, Heather A.; Kathleen A. Martin Ginis, McMaster University; Shawn M. Arent, Rutgers University; Steven R. Bray, McMaster University Body image concerns are ubiquitous among women. Poor body image has been linked to low self-esteem (Levine & Smolak, 2002), depression, and anxiety (Stice & Whitenton, 2002). However, it is not known if body image concerns are related to physiological markers of stress, such as cortisol. Therefore, the purpose of our study was to experimentally manipulate body image to determine if an acute increase in body image disturbance elicits an increase in cortisol secretion. Participants were 43 women (M age = 20.74 years, SD = 2.62) who were randomly assigned to one of two conditions. In the experimental condition, participants were shown a very public, mirrored fitness facility where they were told they would be exercising. They were also given revealing exercise attire, and were told that the session would be videotaped by a man (Gammage et al., 2004). In the control condition, participants were shown a private, nonmirrored fitness room, given nonrevealing exercise attire, and the session was not videotaped. Participants completed a trait and state version of the SPA Scale (Hart et al., 1989) and the BIS Scale (Cash et al., 2002) and provided two saliva samples to measure cortisol secretion before and after the manipulation. Results revealed the experimental condition experienced higher state social physique anxiety (M = 31.9, SD = 8.5) and poorer state body image (M = 24.5, SD = 11.6) after the manipulation than those in the control condition (M = 24.0, SD = 9.0; M = 32.7, SD = 9.1, p = .02). Results also revealed that after the manipulation, the experimental condition had higher cortisol levels (M = .25 mg/dL, SD = .15) than the control condition (M = .16 mg/dL, SD = .09, p = .01), indicating a higher stress response. Finally, regression analyses revealed that situational social physique anxiety explained 7.6% of the variance in postmanipulation cortisol (p = .005). These findings indicate that situational body image concerns increase cortisol. This
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study provides an empirical basis for developing interventions to improve body image and regulate cortisol levels. Sources of social support and perceived competence on same-sex and coed competitive sport teams: Does the athlete’s gender matter? Stuntz, Cheryl P.; Julia K. Sayles, Erin L. McDermott; St. Lawrence University The benefits of attending coed (CE) or same-sex (SS) schools and physical education have been hotly debated (see Mael, Alonso, Gibson, Rogers, & Smith, 2005). Most findings point to different psychological and emotional environments for males and females depending upon the CE or SS nature of the environment, with females generally benefiting more in terms of comfort, support, and feedback in SS than in CE settings (e.g., Derry & Phillips, 2004; Lirrg, 1994; Osborne, Bauer, & Sutliff, 2002). Even though the impact in educationfocused settings has been studied, the impact of participating on SS and CE competitive sport teams has not been examined. This study addressed whether athletes on SS and CE teams differed in the sources of social support as well as sources and level of perceived competence reported. One hundred and ten (62 male, 48 female) collegiate athletes from a variety of sport teams completed questionnaires assessing social support, level of perceived competence, and sources of competence information. A series of group difference analyses with team type and gender as the independent variables and sources of social support, level of perceived competence, and sources of perceived competence as dependent variables were performed. A significant Gender × Team Type interaction effect revealed that males on SS teams perceive more social support from teammates and friends and less support from coaches than males on CE teams. Differences in sources of social support based on team type were much smaller for females. Whereas level of perceived competence did not significantly differ, several sources of perceived competence (e.g., coach evaluation, samesex peer evaluation, effort) significantly differed based on gender and team type. Results are compared to past work in the physical domain (e.g., Horn, Glenn, & Wentzell, 1993; Lirrg, 1993, 1994). The results of this study clearly indicate that male and female athletes experience participating in CE and SS competitive sports differently with regards to sources of social support and competence information. Athlete satisfaction as an outcome of humor styles in recreational sport teams Sullivan, Philip; Kyle Paquette, Brad Rootes; Brock University Humor is a personal attribute that has been researched in team dynamics in a variety of settings (Martin et al., 2003). Recent research on humor in sports has found that it is closely linked to perceptions of team cohesion, particularly individual attraction to group (Sullivan & Brachlow, 2006). However, it appears that Martin et al.’s conceptual model of humor styles may not be valid in sports. As opposed to the original four-factor model, Sullivan and Dithurbide (2007) found support for a two-factor model comprising positive humor directed at teammates, and self-deprecating humor. The current study sought to examine the relationship between humor styles and the outcome of athlete satisfaction, as well as to examine the factor structure of this revised model. A sample of 148 (66 female, 78 male; 4 did not respond) recreational team sport athletes completed a modified (i.e., two-factor) version of the Humour Styles Questionnaire and an abbreviated version of the Athlete Satisfaction Questionnaire (per Eys et al., 2007) that measured satisfaction with respect to
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individual and team performance, team task contributions, and team integration. The scales were counterbalanced across the sample. Although the sample was small, a preliminary confirmatory factor analysis was run to examine the fit of the data to the two-factor model from the previous EFA. Results showed adequate fit (robust CFI = .922, robust RMSEA = .052). All factors of both the ASQ and HSQ were normally distributed and showed acceptable levels of internal consistency. A set correlation analysis was then conducted to examine the relationship between these two sets of variables. Results showed that there is a significant, but small multivariate correlation between the constructs, and further that athlete satisfaction with respect to team integration and team task coordination is significantly predicted by humor styles, particularly positive team-oriented humor. Ways of learning to cope among female adolescent basketball players during a season Tamminen, Katherine A.; Nicholas L. Holt, University of Alberta We examined ways in which athletes learned to cope with stressors over the course of a competitive basketball season. This study was guided by proactive coping theory (Aspinwall & Taylor, 1997). Proactive coping consists of efforts undertaken in advance of the occurrence of a potential stressor in order to avoid it or minimize its severity. This theory emphasizes the individual’s coping resources as well as the recognition of stressors and the elicitation and use of feedback in learning about past coping efforts. Thirteen female basketball players (M age = 16 years) completed pre- and postseason interviews and maintained audio diaries during the season. Through idiographic analyses, individual coping profiles were created and athletes were grouped into two types of coping approaches: A reactive-exploratory coping approach (10 athletes) and a proactive coping approach (3 athletes). During the early season, athletes who used the reactive-exploratory approach tended react to stressors rather than anticipate them. However, as the season progressed, these athletes appeared to evaluate their previous coping efforts and plan ahead for future stressors. Their perceptions of coping effectiveness also improved as the season progressed. Athletes grouped as having a proactive approach planned their coping and used feedback to evaluate success consistently from the start of the season. Their coping also appeared to improve as the season progressed. Results suggest that temporal aspects in the deployment of coping strategies and eliciting and using feedback about coping efforts were important features of how these athletes learned to cope over the season. Furthermore, the results suggest that proactive coping theory may be a useful framework for assessing coping in sport. Motivational predictors of students’ leisure time physical activity and general physical self concept in physical education: A multilevel growth curve analysis Taylor, Ian M.; Kingston University; Nikos Ntoumanis, University of Birmingham; Martyn Standage, University of Bath; Chris M. Spray, Loughborough University Embedded in self-determination theory, this study explored the degree to which changes in Physical education (PE) students’ psychological needs and their motivational regulations for PE predict changes in their general physical self concept (GPSC) and leisure-time physical activity behavior (LTPA). Extending previous research, this study explored change at the intra- and inter-individual levels of two important motivational consequences in PE. Physical education students (N = 178) aged between 11 and 16 years (M = 13.82, SD = 1.29, 69%
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male) were asked to complete a multisection inventory at the beginning, middle, and end of a school semester. Linear multilevel growth models revealed that, of the three needs, only changes in perceived competence positively predicted changes in LTPA and GPSC at the intra- and interindividual levels. In addition, a significant Time × Perceived Competence interaction was found, indicating that students with high levels of perceived competence increased their physical activity levels more over time compared to students with low levels of perceived competence. Of the five motivational regulations, changes in intrinsic motivation positively predicted changes in GPSC at the inter- and intraindividual levels. Also, changes in external regulation positively predicted changes in GSPC at the intraindividual level. Moreover, changes in LTPA were positively predicted by changes in identified regulation at the intraindividual level, as well as intrinsic motivation at the interindividual level. Finally, a significant Time × Intrinsic Motivation interaction was found, indicating that students with high levels of intrinsic motivation increased their physical self-concept more over time when compared with students with low levels of intrinsic motivation. The results underscore the importance of facilitating students’ perceived competence and selfdetermined regulations in PE. Domain specific coping as intermediate processes in the relationships between dispositional optimism-pessimism and satisfaction in the school and sport domains Thompson, Amanda S.; Patrick Gaudreau, University of Ottawa; Sharleen D. Hoar, University of Lethbridge; Valerie Hadd, University of British Columbia; Jonathan Lelièvre, University of Ottawa Prior research has revealed that optimism-pessimism plays a role in the differential use of coping skills in both athletes (Gaudreau & Blondin, 2004) and students (Thompson & Gaudreau, 2007), but limited attention has been allocated to the student-athlete population. The focus of this study was to investigate domain specific coping skills as intermediate processes in the relationship between dispositional optimism-pessimism and the multidimensional life-satisfaction of student-athletes. Initially, a sample of 146 high school student-athletes completed measures of optimism and general life-satisfaction. After a final exam and sport competition, respectively, participants completed measures of academic coping and academic satisfaction and sport coping and sport satisfaction. Using structural equation modeling with manifest variables, dispositional optimism was a significant predictor of academic (β = .29, p < .05) and sport (β = .24, p < .05) task-oriented coping. Academic task-oriented coping was a significant predictor of school satisfaction (β = .32, p < .05), whereas sport task-oriented coping was a significant predictor of sport satisfaction (β = .38, p < .05). In contrast, dispositional pessimism was a significant predictor of both academic (β = .27, p < .05) and sport (β = .29, p < .05) disengagement-oriented coping. In turn, academic disengagement-oriented coping was negatively related to academic satisfaction (β = − .39, p < .05), whereas the use of sport disengagement-oriented coping was negatively related to sport satisfaction (β = −.37, p < .05). Furthermore, domain specific task-oriented coping mediated the relationship between optimism and domain specific satisfaction (indirect effects: β = .09, p < .05; β = .09, p < .05). Complementary analyses revealed no significant cross-domain effects between coping and satisfaction. This research highlights the importance of self-regulation in explaining the relationship between dispositional expectancies and psychological adjustment of individuals participating in multiple activities.
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Mood and enjoyment following 10 and 30 minutes of cycling: The role of cycling enjoyment Tobar, David A.; Nicole Serene, Bowling Green State University The purpose of this study was to determine the role of cycling enjoyment on mood and enjoyment following 10 and 30 min of cycling at a moderate intensity. College students (N = 47) completed 10- and 30-min cycling (counterbalanced) on an upright cycle ergometer in a laboratory. Cycling conditions were completed on separate days at the same time of day. RPE and HR were collected at 3-min intervals during exercise, and participants could adjust the resistance to maintain an RPE of 13. Cycling enjoyment (PACES-Trait) was assessed prior to the 1st cycling condition on a separate day, and low (LCE) and high (HCE) cycling enjoyment groups were formed using a median split procedure. Mood (POMS) was measured at pre-, 5 min post-, and 20 min postexercise, and enjoyment (PACES-State) was measured only at 5 min postexercise. Data were analyzed using repeated-measures MANOVA and ANOVA. Independent variables included groups (LCE, HCE), conditions (10 min, 30 min), and time (pre, post-5, post-20). Groups did not differ in average HR for either condition. Results revealed a significant time effect for tension (p < .001), depression (p < .001), anger (p < .001), vigor (p < .05), fatigue (p < .01), confusion (p < .001), and total mood (TM: p < .005). Mood states improved following exercise. A Group × Conditions × Time effect was found for TM (p < .05). For 10-min cycling, the LCE reported a greater improvement in TM compared to HCE at 5 and 20 min after. For 30-min cycling, the improvement in TM was evident only at 5 min after for the LCE, whereas the HCE reported improvement at 5 and 20 min postexercise. A group effect and a Group × Conditions effect were found for enjoyment (p < .05). HCE reported similar postexercise enjoyment for both cycling conditions, whereas LCE reported significantly lower postexercise enjoyment for 10-min cycling. No other main or interaction effects were found (p > .05). These findings suggest that 10 and 30 min of cycling are associated with similar improvements in mood, but cycling enjoyment and exercise duration do influence postexercise enjoyment and total mood. The utility of motivation regulation profiles for understanding students experiences in physical education Ullrich-French, Sarah C.; Purdue University; Anne E. Cox, Illinois State University Self-determined motivation is desirable in physical education, relating positively to students’ effort, enjoyment, and physical activity out of school (see Hagger & Chatzisarantis, 2007). A popular approach to assessing self-determined motivation is to create a relative autonomy index (RAI; see Vallerand, 1997) by weighting different motivational regulations to form one score. Though accounting for the multidimensionality of motivation, different combinations of motivational regulations are not captured and it is possible for different combinations to result in the same RAI score. To address this issue, cluster analysis was used to identify distinct motivational profiles of external, introjected, and identified regulation, and intrinsic motivation. The utility of this approach was examined by testing for differences in theoretical antecedents (competence, autonomy, relatedness, and consequences enjoyment) of motivation among profiles. Middle school PE students (N = 384) completed a survey containing valid and reliable measures of study variables. Cluster analysis revealed four motivation profiles: externally regulated (n = 59), motivated (n = 147), self-determined (n = 109), and amotivated (n = 69). An ANOVA showed the profiles differed on the RAI, F(3, 1) = 367.24, p < .01; ηp2 = .74. Pairwise comparisons indicated all profiles differed on the RAI except
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the motivated and amotivated profiles. A MANOVA revealed differences among profiles on theoretically relevant constructs, Pillai’s trace = .55; F(4, 12) = 21.43, p < .01; ηp2 = .18. Follow-up ANOVAs indicated that enjoyment differed (p < .01) among all profiles. Profiles also differed on perceived competence, autonomy, and relatedness (p < .05) with the exception of the motivated and self-determined profiles. Profile differences on study variables were consistent with theory. Of note is that the motivated and amotivated profiles differed on all study variables though their RAI scores did not differ. Findings suggest that the motivational profiles provide unique information over and above the RAI. Cardiorespiratory and cortisol responses to mental challenges during exercise in high and low-fit females Webb, Heather E.; Supatchara E. Tangsilsat, Kelly A. McLeod; University of New South Wales; Edmund O. Acevedo, Virginia Commonwealth University Stress responses to physical and mental challenges are regulated by hormones released following activation of the sympathoadrenal (SA) axis and the hypothalamo-pituitaryadrenocortical (HPA) axis. This activation subsequently results in increased cardiorespiratory (CR) responses and cortisol (CORT) levels. However, the impact of CR fitness on the combination of mental and physical stress has not been investigated beyond activation of the SA axis. This study compared CR and CORT responses in females of below-average fitness (VO2max = 31.30 ± 2.59 mL/kg/min-1) and above-average fitness (VO2max = 48.41 ± 3.4 mL/kg/min-1). Twenty-four apparently healthy females (12 high fit [HF] and 12 low fit [LF]) participated in two counterbalanced experimental conditions. In the dual-stress condition (DSC), the participants were mentally challenged while exercising on a cycle ergometer at 60% of VO2max, whereas in the exercise-alone condition (EAC) the participants exercised at the same intensity without the mental challenge. State anxiety measures and the NASA Task Load Index (NTLX) were used to assess the perceived mental and physical workload during each condition. NTLX scores were significantly greater in the DSC. The DSC also elicited greater elevations in heart rate, respiration rate, ventilation, ventilatory efficiency, and cortisol values than the EAC. Additionally, HF participants demonstrated no differences compared to LF participants in CR variables at the conclusion of the DSC, although cortisol levels were significantly lower for the HF participants compared to the LF participants. The combination of a mental and physical challenge resulted in an increase in CR responses and an activation of the HPA axis. Furthermore, although HF participants did not differ from the LF participants in CR responses to the DSC, cortisol levels were attenuated for the HF participants. Thus, suggesting that greater cardiorespiratory fitness may attenuate HPA axis responses to concomitant stressors or high stress conditions. Summarizing the efficacy of public-access stair climbing interventions: A data synthesis Webb, Oliver J.; Loughborough University; Frank F. Eves, University of Birmingham Stair climbing is a freely available activity with proven health benefits. Previous interventions in public-access sites sought to encourage stair choice by introducing simple message prompts adjacent to the stairs and escalators. To verify the efficacy of this intervention format we initiated a research synthesis. Data from 20 comparable studies was combined to produce a total sample of 468,059 pedestrian observations, which was analyzed using logistic regression. This approach was preferred to traditional meta-analysis, as it enabled
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the exploration of interactive relationships in addition to main effects. Several demographic variables were shown to have main effects: males, under 60s, Whites, and those without children/bags all climbed the stairs more than their counterparts. Stair climbing was also positively influenced by the volume of pedestrian traffic. In train stations, prompts increased stair climbing by an odds ratio (OR) of 1.08. In malls, greater effects were produced, OR = 2.10. Baseline differences most likely explain this disparity; baseline stair climbing is higher in stations (40.9%) than in malls (8.1%), leaving fewer potential converts. In malls, the effects of message prompts were found to interact both with gender and ethnicity, such that women and non-Whites increased their stair use more markedly. Curiously, station data showed different interaction effects, with more pronounced responses among males. Evidence of differential responding warrants further investigation, possibly using qualitative methods. The enhanced effects among women and non-Whites can be met with cautious optimism, however, given the heightened risk of certain morbidities among these groups. Further analyses will incorporate additional variables, such as weather conditions and physical specifications (e.g., stair height). This project helps to clarify the determinants of pedestrian behavior and the potential impact of message prompts. Overall, our findings corroborate the efficacy of promoting stair climbing as a means of elevating population activity levels. Understanding sport commitment in senior bowlers Weir, Patricia L., University of Windsor; Nikola Medic, University of Western Australia; Joe Baker, York University; Janet L Starkes, McMaster University Understanding the nature of long-term motivation in older exercisers may play a critical role in promoting adherence to physical activity across the lifespan. The purpose of this study was to examine functional and obligatory sport commitment in 91 senior bowlers (68 male; 22 female; M age = 65 ± 9 years) sampled from local bowling centers. The conceptual framework encompassed the sport commitment model (Scanlan et al., 1993); participants completed a sport-modified version of the Exercise Commitment Scale (Wilson et al., 2004), which assessed the two dimensions of sport commitment (functional and obligatory) along with its determinants in adult exercisers. Simultaneous linear regression analyses revealed that the determinants explained 84.8% of the variance in functional commitment (p < .001), with satisfaction and personal investment as the only significant predictors. For obligatory commitment, the model explained 60.7% of the variance (p < .001) with satisfaction, social constraints, involvement alternatives, and personal investment as significant predictors. Overall, these data replicate and extend the findings of Scanlan et al. (1993) and Wilson et al. (2004) that bowlers have higher functional than obligatory commitment.. Furthermore, both functional and obligatory commitments are determined by higher satisfaction and personal investments, whereas obligatory commitment is also predicted by higher social pressures to continue to participate and higher attractiveness of the most preferred alternative activities. Overall, this study indicated that the sport commitment model may be useful for understanding motivated behavior of older athletes. Lessons learned and core values adopted in a sport-based youth development program: A longitudinal qualitative analysis Weiss, Maureen R.; Jennifer A. Bhalla, Nicole D. Bolter, Melissa S. Price; University of Minnesota
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Longitudinal evaluation research is needed to document the effectiveness of sport-based youth development programs in teaching life skills. Using a longitudinal qualitative design (Gilmartin, 2006; Saldaña, 2003), we analyzed knowledge and transfer of life skills in 18 youth (ages 10 to 19) over the course of three years. Youth were participants in the First Tee, a program whose goal is to foster positive development by using golf as a context and coaches as external resources to teach life skills. In-depth interviews were conducted each year to determine the extent to which youth transfer life skills learned in the golf context to multiple domains. Interview questions in Years 2 and 3 were customized to each respondent’s narrative in previous years. Inductive content analyses were coded for between- and withinparticipant change to document (a) convincing evidence of life skills transfer, (b) domains in which life skills are used, (c) themes characterizing use of life skills, and (d) compelling quotes showing successful life skills transfer. Findings showed that 89% of youth provided convincing evidence of retaining knowledge and transfer of life skills over the three-year period, including emotion management, goal setting, coping with challenges, resolving conflicts, and helping others. Participants were consistent in using these life skills in many domains including school, home, friends, job, and extracurricular activities. Common themes such as STAR (stop, think, anticipate, respond) and goal ladder (sequential goals coupled with strategies to achieving them) emerged over time for self-management, resolving conflicts, and goal setting. Participants increasingly alluded to life skills becoming automated over time, in much the same way physical skills do. Many rich quotes were derived that convey compelling evidence of successful life skills transfer over time in multiple domains and using several thematic strategies. These longitudinal qualitative data provide evidence that the First Tee is effective in attaining its goals of teaching life skills. Life skills, youth development, and sport participation: Retention effects over a one-year period Weiss, Maureen R.; Nicole D. Bolter, Jennifer A. Bhalla, Melissa S. Price; University of Minnesota; Ellen S. Markowitz, University of Virginia According to Petitpas et al. (2005), positive youth development is most likely to occur when organized sport programs emphasize a mastery climate (context), positive adult behaviors (external resources), and personal skills (internal assets). The First Tee is a youth development program that has these components in place by using golf as a context and coaches as external resources for teaching life skills to maximize positive psychosocial outcomes. Evaluation research is necessary to document whether sport-based youth development programs, like the First Tee, is effective in achieving its goals. In Year 1, Weiss et al. (2007) found that participants in the First Tee compared favorably to youth involved in other organized activities on life skills transfer, general life skills, and developmental outcomes. While these findings provided evidence of the First Tee’s effectiveness at one occasion, longitudinal research is needed to determine whether positive outcomes are retained over time. Thus the purpose of the present study was to evaluate whether life skills and developmental outcomes of First Tee participants observed in Year 1 remain stable in Year 2. The sample included 303 of 533 participants (ages 10 to 19) from Year 1. First, using the target model of the life skills transfer measure in Year 1, a confirmatory factor analysis at Year 2 showed an acceptable fit (NNFI = .99, RMSEA = .05) of an 8-factor model, providing additional validity for the measure. Second, multivariate analyses of variance showed no significant change in participants’ scores from Year 1 to 2 on most scales of life skills transfer (6 of
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8 scales), general life skills (6 of 8 scales), and developmental outcomes (7 of 10 scales). Third, effect sizes were small (d < .41) in change scores from Year 1 to 2 for all life skills and developmental outcomes. Collectively, findings show stability of life skills learning and developmental outcomes over a one-year period, providing evidence that the First Tee is having a sustained positive impact on youth development. An examination of imagery use and self-efficacy during rehabilitation Wesch, Natascha N.; Craig R Hall, Jan Polgar, Lorie Forwell; University of Western Ontario Sordoni and colleagues (2000, 2002) developed the Athletic Injury Imagery Questionnaire (AIIQ) to measure imagery use in athletic-injury rehabilitation; however, the AIIQ was not developed based on empirical work but on existing theoretical frameworks of athlete’s imagery use in sport training and competition. As a result, Dreidiger, Hall, and Callow (2006) conducted a qualitative study in order to expand the knowledge and increase the understanding of imagery use by athletes in sport-injury rehabilitation. Based on the results from the work by Dreidiger and colleagues (2006), the AIIQ was revised and termed the Injury Rehabilitation Imagery Questionnaire (IRIQ). Objectives: One purpose of the present study was to test the factor validity of the IRIQ. A second purpose of the present study was to revisit the relationships between imagery use, self-efficacy, and adherence in athletic injury rehabilitation using this new instrument. Participants: The IRIQ was administered to 285 athletes, aged 18 to 74 years, undergoing injury rehabilitation. Athletes participated in a wide variety of sports. Main Outcome Measures: IRIQ, the Athletic Injury Self-Efficacy Questionnaire (Milne, Hall, & Forwell, 2005), and an adherence measure. General Results and Conclusions: Support for the factorial validity of the IRIQ was found. Injured athletes used more motivational, pain, and cognitive imagery than healing imagery. Injured athletes were stronger in task than in coping efficacy. Motivational imagery was found to be the strongest predictor of both task and coping efficacy. Motivational imagery was found to be the only significant predictor of rehabilitation adherence, while both task and coping efficacy predicted adherence. Quiet competence: Hidden contributions of trailblazing women in sport and exercise psychology Whaley, Diane E.; University of Virginia; Vikki Krane, Bowling Green State University The written history of sport and exercise psychology provides a fairly comprehensive record of the contributions of prominent males in the field (e.g., Cox, 2001; LeUnes & Nation, 2001; Murphy, 1995; Weinberg & Gould, 2003). The contributions of women sport and exercise psychologists, however, are largely overlooked, even though they have been at the forefront of developing our discipline (Gill, 1995; Vealey, 2006). Using life history methodology, we aimed to explore and document the contributions of eight trailblazing women in sport and exercise psychology. Criteria for inclusion in the study were quantity and significance of scholarly publications, leadership in professional associations, influence on a substantial number of graduate students, and 25 years of professional involvement in sport psychology. Each woman participated in a life history interview lasting 5–8 hours. Additional data were obtained through follow-up conversations, personal and autobiographical writings (e.g., vitae, book chapters, and a focus group interview). This presentation will focus primarily on data from the focus group interview with seven of these women. The principal questions asked
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in this group interview were, (a) what were the most important, yet largely unrecognized, contributions of each woman in the study? and (b) why do you think these contributions were overlooked in our written history? Three major themes about their contributions emerged: competence, commitment, and professionalism. Each of these women engaged in quality mentoring, teaching, research, and service to the profession. They also engaged a multitude of leadership positions in which many “behind the scenes” contributions were made. Based on these findings, we will highlight why we consider each of these women as trailblazers as well as what lessons for the future can be gained from their experiences. Don’t hate me because I’m beautiful: Physical activity, physical attractiveness efficacy, and perceived social acceptance Willow, Jason P.; Gannon University Baumeister and Tice’s (1990) social exclusion theory posits that one of the major processes by which individuals experience anxiety is in response to the threat of exclusion from important social groups. The authors suggest that much of human behavior reflects the attempt to avoid social exclusion and that the perception of exclusion can contribute to other negative affective states, including loneliness, depression, and low self-esteem. The goal of the present study was to examine physical activity as a mechanism for the avoidance of social exclusion. It was hypothesized that there would be a significant positive relationship between physical activity and perceived social acceptance and that this relationship would be mediated by physical attractiveness self-efficacy. Specifically, it was thought that physical activity participation would be positively related to perceived social acceptance but the source of this influence would be the effect that physical activity has on one’s perception of their ability to appear physically attractive in a variety of social situations. Participants in the study were 427 college-aged individuals (mean age 21.9 years) recruited from undergraduate courses at a large Midwestern university. Participants completed a packet of inventories assessing their history of recent physical activity participation in addition to physical, social, and global self-perceptions. Consistent with hypotheses, a significant relationship was revealed between physical activity participation and perceived social acceptance. Furthermore, this relationship was mediated by physical attractiveness self-efficacy. Future research efforts may find value in examining the other sources of social acceptance with reference to physical activity participation. It has become abundantly clear that physical activity is often a socially motivated activity. It will be interesting to examine whether these social motivations have anxieties relating to social exclusion as their source. Support versus control: Parent and adolescent views of social influences following a physical activity lapse Wilson, Kathleen S., Kevin S. Spink, Carly S. Whittaker; University of Saskatchewan Social influences have been conceptualized as being forms of either social control or social support. Further, there has been overlap in their measurement with identical social influences, sometimes identified as control and at other times as support (Duncan et al., 2005; Lewis et al., 2004). Given that perceptions of control and support might have different influences on behavior, understanding the meaning of influences becomes important. The present purpose was to examine whether parents and adolescents view parental influences provided following an activity lapse as control or support. In Study 1, parents (N = 149) were provided with a scenario describing a lapse in their child’s activity, as well as 13 influences they might
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use, and asked the extent to which each influence would be used as control or support. EFA results revealed that the influences could be grouped into positive, negative, and modeling types. A MANOVA revealed significant differences in parents’ views of the influence types (p < .001). Positive and modeling influences were viewed more as support than control (p < .001), whereas no support versus control differences emerged for negative influences. A second study examined adolescents’ (N = 34) views of the intent of parental influences during a previous lapse. Participants were provided with 13 influences that parents might use and asked whether they viewed them as forms of support or control. Influences were grouped into positive, negative, or modeling types. Results from a MANOVA revealed a significant difference in perceptions of support versus control (p < .001). Similar to parents, adolescents viewed positive and modeling influences more as support than control (p < .001), with no difference emerging for negative influences. These findings suggest that while positive and modeling influences are generally viewed more as support than control, negative influences may be viewed as either support or control. Future research should explore how these differences in perceptions, especially for negative influences, impact subsequent behavior change. To nag or not to nag? When do negative parental influences predict adolescent activity behavior? Wilson, Kathleen S.; Kevin S. Spink, Carly S. Whittaker, University of Saskatchewan Social influences can be conceptualized in a number of ways including social control and social support. Previous research (Wilson, Spink, & Whittaker, 2008) has revealed that adolescents may perceive negative social influences (e.g., nagging as either control or support). Given that social support is typically associated with physical activity positively (Sallis et al., 2000) and social control can be either positively or negatively associated with behavior (Tucker & Anders, 2001), suggests that how a social influence is interpreted becomes important to understanding possible behavior change. The purpose of this study was to explore how perceptions of negative social influences as either control or support impact behavior change and affect. Adolescents (n = 34) were asked to recall a time when their activity had lapsed, provided with negative influences that a parent might use to influence them, asked whether their parents used these influences, and whether the influences used were perceived as control or support. Participants were then asked how much their behavior changed and the affect they felt as a result of the influences received. Separate hierarchical regressions were conducted predicting behavior change and affect with use of negative influences entered on the first step, followed by perceptions of the influence as control or support on the second step. Results for behavior change revealed that the use of influences did not predict behavior change (p > .5), whereas perceptions of the influence as control/support did (p < .05). Examination of the individual predictors revealed that those influences associated with greater support predicted more positive behavior change (p < .01). In terms of affect, results revealed that only the perceptions of support and control predicted affect (p < .001). Similar to behavior change, perceiving the negative influence as supportive was associated with more positive affect (p < .001). It appears that the negative social influences provided by parents, when viewed as support by adolescents, may positively impact behavior and affect. An imagery intervention with young figure skaters Wiman, Melissa; Craig Hall, University of Western Ontario
Sport and Exercise Psychology S213
Most of the imagery research in sport has focused on adult athletes. Recently, imagery use by young athletes has received some attention. Munroe-Chandler, Hall, Fishburne, and Strachan (2007) sought to gain insight into imagery usage in young athletes in a variety of sport between the ages of 7 and 14 years. Results indicated that females between 7 and 14 years engaged in motivational general-mastery (MG-M) imagery. To further investigate MG-M imagery use in young female athletes, an intervention was given to a group of six figure skaters between the ages of 10 and 15 via a single-subject, multiple baseline design. The skaters were split into two groups based on skating level. All six participants underwent three weeks of baseline testing, completing the CSAI-2- C, SEQ-C, TSCI to measure confidence, and SIQ-C and IUQ-R Figure Skating to measure imagery use. Following the baseline period, Group 1 received the MG-M intervention for four weeks while Group 2 continued with the baseline phase. At the end of these 4 weeks, Group 2 started the MG-M intervention, which was another 4 weeks in duration. During the intervention period, the co-investigator met with the participants weekly after or before practice to administer the aforementioned questionnaires and lead the participants in an imagery session. The skaters were required to read a script that focused on confidence. The participants were asked to read the script daily on their own. Results indicated an improvement in confidence scores for five of six participants as evidenced by an increase in their scores on the confidence measures from baseline. Imagery usage, as measured by the SIQ (MG-M subscale), increased over the course of the intervention, indicating a positive relationship between imagery usage and increased confidence. That is, a larger increase in MG-M imagery use was associated with a larger improvement in confidence scores. No evidence of relative age effects among Canadian figure skaters and artistic gymnasts Wong, Harmonie R.; York University; Stephen Cobley, Leeds Metropolitan University; Joe Baker, York University Sports use cutoff dates in an attempt to provide fair competition by controlling for the effects of developmental differences. However, extensive research shows that developmental differences within age groups can be substantial. Consequences resulting from these differences are referred to as relative age effects and can predispose athletes to higher levels of achievement. Previous evidence has shown a repeated over-representations of players born in the first three months of a sport’s selection year (i.e., after a sport’s cutoff date) in many sports. However, further research needs to explore relative age effects in aesthetic sports where the role of maturational factors may be atypical. In figure skating, the cutoff date is July 1st, whereas, in gymnastics, the cutoff date is January 1st. Research (St. Marie et al., 2000) has suggested that in gymnastics, being early born (i.e., being relatively older) produces a performance disadvantage, as height and mass gain can impede flexibility, rotational speed and strength to mass ratio. As a result, their data showed a flip-flop birth date pattern compared to other sports. The purpose of this study was to examine relative age as it relates to the development of Canadian figure skaters and artistic gymnasts at the junior and senior national levels. Data were obtained from official sources and resulted in birth date information for 378 figure skaters and 144 artistic gymnasts. Results revealed no significant patterns between relative age and higher levels of competition among both artistic gymnasts and figure skaters. The lack of consistency in relative age patterns suggests the social factors underpinning performance in aesthetic sports may be different from nonaesthetic sports.
S214 2008 NASPSPA Free Communications: Verbal and Poster
Further research is necessary to confirm these results; however, they provide additional evidence regarding the complexity of relative age effects. Physical activity, brain function, and the role of the apolipoprotein E4 allele in young adults Woo, Minjung; Stephen Roth, Bradley Hatfield; University of Maryland The beneficial effect of exercise on cognitive function has been established in normal aging and even in children. Particularly, the benefit of exercise was of greatest magnitude for executive processes. However, the link between exercise and brain function is modified by genetic factors in older adults. Specifically, physical activity in carriers of the apolipoprotein E e4 allele, a genetic risk factor for Alzheimer’s disease, was highly protective against cognitive decline. However, it is unclear if physical activity would compensate for the negative impact of the e4 allele in young healthy adults. Therefore, the purpose of this study was to investigate the interactive relationship between physical activity and genotype to brain function in college age males and females during executive and nonexecutive challenge. Participants were 41 young (M = 20.6 years) healthy e4 carriers (N = 12) and noncarriers (N = 29) who underwent fitness testing to estimate aerobic capacity VO2max. Brain function was assessed by a neuroelectric measurement, the event-related potential. P300 amplitude and latency for each of the electrodes at Fz, F3, F4, Cz, C3, C4, Pz, P3, P4, O1, and O2 during oddball and no-go tasks were regressed separately in a series of a hierarchical regression on the following predictor variables: (1) genotype, (2) aerobic capacity, and (3) the interaction of genotype and aerobic capacity. In no-go task, VO2max was positively associated with P300 amplitude in the parietal region, Δ R2 = 0.25, p = 0.05 in e4 carriers; Δ R2 = 0.02, p = 0.22 for noncarrier and negatively related to P300 latency in the frontal region in e4 carriers Δ R2 = 0.27, p = 0.04 for e4 carriers; Δ R2 = 0.05, p = 0.30 for noncarrier. As reported, no such significant effects were observed in noncarriers. The current finding revealed that there is genetic specificity in the relationship between exercise and brain function in young healthy adults. Therefore, the neurobiological benefit of exercise is apparent in those who are at risk of dementia even during adolescence. Effects of self-regulatory strength depletion on muscular performance in older adults Woodgate, Jennifer; Steven R. Bray, Kathleen A. Martin Ginis, Audrey L. Hicks; McMaster University The limited strength model of self-regulation (Schmeichel & Baumeister, 2004) has generated a considerable body of evidence consistent with the view that acute depletion of people’s self-regulatory capacities imparts negative effects on subsequent tasks requiring self-regulation. However, virtually all the evidence established thus far has been derived from studies involving undergraduate students. In the present study, we aimed to extend previous work investigating the after-effects of a self-regulatory depletion task on physical stamina in a sample of older adults. A convenience sample of older adults (N = 41; M age = 71.64 ± 7.27) were stratified by gender and randomized to either a cognitive depletion condition (modified Stroop task) or a control (color word) group and completed two maximal isometric exercise endurance trials separated by the cognitive task. A one-way ANOVA was computed to compare the residualized change scores across the two endurance trials between the experimental and control conditions. Results showed a significant difference
Sport and Exercise Psychology S215
between groups, F(1, 39) = 5.72, p < .05, in which the experimental group’s performance declined (Mexp. = −6.47 ± 19.64 s) whereas the control group’s performance increased (Mcontrol = +7.59 ± 17.91 s) after the cognitive manipulation task. Results lend broader support to Baumeister’s limited strength model and its generalizability to older adults. Findings are contrasted with similar studies involving younger adults and interpreted in light of biological aging processes. Implications for self-regulatory challenges faced by many older adults and potentially severe consequences of self-regulatory failures are discussed along with recommendations based on recent work examining self-regulatory training and dietary supplementation interventions.
Sponsorship Acknowledgments NASPSPA 2008 thanks the following sponsors for their financial support.
Applied Science Laboratories (http://www.a-s-l.com/)
Delsys Incorporated (www.delsys.com)
Department of Kinesiology, McMaster University (http://www.mcmaster.ca/kinesiology/)
Human Kinetics Incorporated (www.humankinetics.com)
Lafayette Instrument (www.lafayetteinstrument.com)
The Magstim Company Limited (www.magstim.com)
Northern Digital Incorporated (www.ndigital.com/research)
Phoenix Technologies Incorporated (http://www.ptiphoenix.com/)
Translucent Technologies Incorporated (http://www.translucent.ca/)
NASPSPA 2007 Conference: Emendation The following abstracts are published in the 2007 JSEP Supplement but were not presented at the 2007 NASPSPA Conference. 1. Comparing balance and posture control mechanisms among children with ADHD under off-medication and on-medication conditions (Aranha & Roncesvalles) 2. Speed-accuracy trade-off in cyclic and discrete tasks (Okazaki, Okazaki, & Teixeira) 3. Pain perceptions, depression and reaction time in women with fibromyalgia syndrome (Sanches, Luft, Fonseca, Goncalves, & Andrade) 4. Competitive anxiety in handicapped athletes (Brandt, da Cruz, Rocha, Andrade, & Viana) 5. Self-efficacy of active and non-active adolescents (Rolim, Matias, Segato, & Andrade) 6. Effect of choice in motor learning (Schweighofer)
Abstract Author Index Abel, Mark F. 62 Abernethy, Bruce A. 61, 82, 95, 108, 111 Acevedo, Edmund O. 207 Adkin, Allan L. 32, 127 Allen, Justine B. 146 Almeida, Gil L. 79 Almeida, Jude 33 Almeida, Quincy J. 61, 110, 124, 125, 136 Aluko, Oluwatoni E. 48 Amazeen, Eric L. 136 Amazeen, Polemnia G. 89 Amirthavasar, Gaya 146 Ammar, Diala F. 62 Amorose, Anthony J. 147 Anderson, David I. 38, 137 Anderson, Ross 47 Anderson, Timothy 111 Anderson-Butcher, Dawn 147 Angulo-Barroso, Rosa 40 Arbour, Kelly P. 148, 149 Arent, Shawn M. 6, 202 Armstrong, Nicole A. 148 Arsenault, Andre 192 Ashford, Kelly J. 177 Augaitis, Lina 18 Aune, Andrew 74 Avery-Epps, Regina 28 Ayaz, Hasan 130 Babanin, Mikhail 11 Backstein, David 125 Bacon, Simon L. 192 Baker, Frank 152 Baker, Joseph 14, 15, 16, 18, 37, 182, 187, 208, 213 Baker, Tom 162 Balzer, Warren 75 Barbu-Roth, Marianne 38 Bardy, Benoit G. 21, 84 Barela, Jose A. 38, 41, 56 Barnes, Robert T. 148 Barr, Neil 149 Barros, Joao A.D.C. 76 Bassett, Rebecca L. 149 Baynard, Tracy 114 Bean, Eric A. 166 Beauchamp, Mark R. 30, 154, 161, 188 Bellan, Pâmela 55
Bellinger, David B. 63 Benda, Rodolfo N. 135, 137 Bennett, Bradford C. 62 Bennett, Simon J. 45, 88, 105 Berg, William P. 63, 133 Bernardin, Brandon J. 63 Bhalla, Jennifer A. 208, 209 Binsted, Gordon 64 Bischoff, Matthias 107 Bishop, Daniel T. 150 Bittner, Jennifer P. 150 Black, Sandra E. 124 Blaesing, Bettina E. 151 Blanchard, Chris M. 152, 172 Blandin, Yannick 65 Blanke, Dan 112 Bloom, Gordon A. 174 Bloom, Jarred 29 Blum, Brittany L. 152 Boardley, Ian D. 153, 154 Bolter, Nicole D. 208, 209 Bonnet, Cedrick T. 65 Bootsma, Reinoud 93 Boutin, Arnaud 65 Bowcock, Alison 115 Boxell, Rachel L. 76 Branta, Crystal 39 Bräutigam, Helge 15 Brawley, Lawrence R. 6, 168, 171, 175 Bray, Steven R. 146, 154, 159, 161, 178, 185, 196, 202, 214 Briki, Walid 170 Brosvic, Gary 155 Bruce, Lyndell 66 Brugger, Peter 151 Brunel, Philippe C. 197 Bruner, Mark W. 19, 154, 156 Brunet, Jennifer 156 Bryden, Pamela J. 66, 110, 116 Brydges, Ryan N. 67 Buchanan, John J. 42, 73, 100, 128 Buckingham, Gavin 64 Budde, Bradley M. 63 Bunce, Scott C. 130 Burke, Jeanmarie 119 Burke, Shauna M. 184 Büsch, Dirk 15 Button, Chris 67 Buultjens, Phillip 111
Note. The page numbers listed in this index refer to the pages numbered S1 through S215 in this publication. S217
S218 Abstract Author Index
Caçola, Priscila M. 40, 68, 142 Caldwell, Graham E. 87, 88 Calvin, Sarah 96 Cañal-Bruland, Rouwen 68, 85, 139, 198 Capparelli, Sofia V. 91 Carello, Claudia 65 Carey, David 64 Carlsen, Anthony N. 69 Carlson, Linda E. 162 Carlton, Les G. 72, 115 Carnahan, Heather 67, 125 Carpenter, Mark G. 30 Carraro, Natasha 157 Carron, Albert V. 184 Carson, Sarah 157 Carvalho, M.F.S.P. 135 Cauraugh, James H. 3, 80, 107 Cavanaugh, Jim 100 Cessna, Trevor 29 Chang, Chih-hui 69 Chang, Yu Kai 26 Chapman, Chris 14 Chen, Chih-Chia 124 Chen, David D. 118 Chen, Hsiu-hui 70 Chen, Li-Chiou 40 Chen, Miaowei 70 Chen, Robert 8 Chen, Shing-jye 112 Cheng, Kuang Chih 71 Cheng, Wen-Nuan K. 158 Cheung, Teresa 139 Chevalier, James 120 Cheyne, Douglas 139 Chiang, Huai-Hsiao H. 71 Chow, Graig M. 158, 164, 175 Christopher, Bonny 99 Chua, Romeo 34, 69, 75 Chung, Linda 121 Chung, Yongchul 28 Chung, Yuan 71 Clark, Jane E. 48, 54, 57, 73, 117, 195 Clayton, Courtney S. 159 Clayton, Linwood B. 200 Cobley, Stephen P. 14, 15, 16, 37, 213 Cohn, Tony 172 Coker, Cheryl A. 72 Conroy, David E. 160 Contakos, Jonas 72 Cook, Brian J. 160
Cooke, Carlton 14 Coombes, Stephen A. 80, 90, 107, 148 Cooper, Jillian 147 Cope, Cassandra J. 161 Cordova, Alberto 40, 41 Côté, Jean 19, 167 Cox, Anne E. 206 Cramp, Anita G. 161 Crocker, Peter R.E. 18, 30, 186, 191 Culos-Reed, S. Nicole 162 Cumming, Jennifer 201 Cunningham, Ian J. 162 Cybucki, Janet 75 D’Amore, Alicia 81 Davis Marchand, Hannah 163 De Bourdeaudhuij, Ilse M. 22, 43 De Clercq, Dirk L. 105 de Freitas, Paulo B. 41 Dean, Noah J. 42, 73 Decker, Leslie 97 Deconinck, Frederik J.A. 21, 22 Deeny, Sean P. 124 Deffeyes, Joan E. 43, 46, 50 Deforche, Benedicte I. 22, 43 Delignieres, Didier 8, 9 Desmarais, Genevieve 116 D’Hondt, Eva M.G. 22, 43 Dickey, Gwyneth R. 73 Dickin, D. Clark 74 Dicks, Matthew 67 DiNallo, Jennifer M. 194 Dithurbide, Lori 164 Diz, Maria Angelica R. 44 Dorsch, Travis E. 164 Douglas, Haylie 113 Drake, Rosanna 29 Dubrowski, Adam 67, 125 Duda, Joan L. 3, 199 Dufek, Janet S. 140 Dunlop, Nicole 152 Dunn, Andrew S. 119 Dunn, Robin 45 Durand-Bush, Natalie 34 Edwards, Christopher A. 18, 75 Eid, Michael 111 Eisenmann, Joe 39 Ekkekakis, Panteleimon 35 Eliasz, Kinga L. 32, 127
Abstract Author Index S219
Elliott, Digby 83, 86 Englert, Nicole C. 31 Erickson, Karl 19 Etnier, Jennifer L. 6, 24, 25, 26, 169, 193 Etnyre, Bruce 75 Eves, Frank F. 207 Eykens, Katie 170 Eys, Mark A. 161, 162 Fairbrother, Jeffrey T. 28, 76, 77, 143 Farrow, Damian T. 66, 77, 82, 108, 111, 122 Faulkner, Guy 172 Fecteau, Marie-Claude 165 Felbaum, Daniel 29 Feltham, Max G. 44, 45 Feltz, Deborah L. 6, 158, 170, 175, 197 Fenton, Lindsay R. 165 Fernandez, Laure 93 Fernhall, Bo 114 Ferracioli, Marcela C. 55 Fialho, Joao Vitor A.P. 78 Fifer, Angela M. 166 Filipi, Mary L. 92 Fischman, Mark G. 56, 78 Focht, Brian 166 Fonseca, Fabiano S. 135 Fontana, Fabio E. 191 Ford, Paul R. 17, 29, 181 Forwell, Lorie 210 Francois, Sara J. 35 Franks, Ian M. 69 Franz, Elizabeth A. 91 Fraser-Thomas, Jessica L. 167 Freitas, Sandra M.S.F. 79 Fries, Udo 65 Fuller, Daniel L. 168 Furtado, Ovande 191 Gabbard, Carl P. 40, 41, 42, 62 Gabriel, David A. 178 Gagen, Linda M. 60 Gamble, Kelly M. 80, 90 Gammage, Kimberley L. 32, 168, 178 Gapin, Jennifer I. 25, 26, 169 Garner, Joanna K. 152 Gaudreau, Patrick 157, 165, 169, 205 Gay, Jennifer L. 188 Geh, Carolyn L.M. 30 Gernigon, Christophe 170, 180
Gilden, David L. 9, 10 Gill, Diane 193 Gilson, Todd A. 170 Giuffrida, Clare 80 Givens, M. Russell 20, 21 Glazebrook, Karen E. 171 Godbolt, Bryan 82 Godde, Ben 11, 36 Godoi, Daniela 56 Goh, Hui-Ting 81 Gonzales, Laura M. 89 Gonzalez, David A. 81, 104 Good, Christopher J. 119 Goodman, Simon R. 31 Goodway, Jacqueline D. 45, 57 Gorczynski, Paul 172, 187 Gorelick, Mark 137 Gorman, Adam D. 82 Gould, Daniel R. 6, 157, 166 Gradkowski, Ashlee 82 Granados, Carolina 140 Grattan, Kimberly P. 172, 173 Gravenhorst, Robynne 80 Gregg, Matthew 74 Gregson, Paige 173 Grevlos, Mike C. 30 Grierson, Lawrence E. 83 Grove, Colin R. 51 Guan, Hongwei 84 Guérin, Perrine 84 Gunnell, Katie E. 173, 191 Gyurcsik, Nancy C. 168 Hadd, Valerie 186, 205 Hagemann, Eric 125 Hagemann, Norbert 85, 139, 182, 201 Haibach, Pamela S. 86 Hale, Bruce D. 101, 152 Hall, Craig R. 179, 187, 190, 210, 212 Han, Dongwook 100 Hancock, David J. 174 Hansen, Steve D. 81, 86 Harbourne, Regina T. 43, 46, 50 Hardy, Lew 158 Hassell, Kristina A. 174 Hasson, Christopher J. 87, 88 Hately-Aldous, Susi 162 Hatfield, Bradley D. 6, 31, 117, 124, 195, 214 Haubenstricker, John 39
S220 Abstract Author Index
Haufler, Amy J. 31, 124 Hausenblas, Heather A. 160 Hayes, Spencer J. 88 Heath, Matthew 2, 64, 82, 113 Heffernan, Kevin S. 114 Hegele, Mathias 11, 13 Hendrick, Joy L. 89 Hepler, Teri J. 39, 158, 175 Hessler, Eric E. 89 Heuer, Herbert 13 Hicks, Audrey L. 214 Higgins, Torrance J. 90 Hillman, Charles H. 126 Hiraga, Cynthia Y. 44, 55 Hoar, Sharleen D. 154, 205 Hodges, Nicola J. 18, 34, 75, 90, 115 Hohmann, Tanja 111 Holt, Nicholas L. 185, 204 Hong, Lee 95 Horn, Robert R. 91 Horn, Thelma S. 165 Hsu, Jeffrey 73 Hsueh, Cheng-Kai 71 Huang, Junfeng 54 Huffman, Jennifer L. 32, 127 Hughes, Charmayne M. 91 Huisinga, Jessie M. 92 Hunley, Julie H. 51 Hunter, Elaine L. 49 Hurmeric, Irmak 45 Huys, Raoul 93, 96, 139 Inglis, J. T. 69 Ishibashi, Yukimasa 93 Ishikura, Tadao 94, 104 Iteya, Misaki 53 Ives, Jeffrey C. 31 Iivonen, Susanna 46 Izzetoglu, Kurtulus 130 Izzetoglu, Meltem 130 Jaakkola, Timo T. 94 Jackson, Robin C. 61, 95, 177 Jaeger, Lukas 48 James, Eric G. 95 Janelle, Christopher M. 80, 90, 107, 148 Jeka, John J. 56 Jenkins, Marj E. 136 Jensen, Jody L. 33, 52 Jirsa, Viktor 93, 96
Johanning, Jason 112 Johnson, Andrew M. 136 Johnson, Erica N. 57 Jol, Ingeborg 143 Jordan, Azizah 20 Jung, Mary E. 175 Jutila, Ari A. 94 Kadivar, Zahra 96 Kagerer, Florian A. 48, 117 Kalaja, Sami P. 94 Kantak, Shailesh S. 97 Karageorghis, Costas I. 150 Karoly, Paul 183 Kato, Takaaki 93, 113 Katsavelis, Dimitrios 97 Kavussanu, Maria 153, 154 Kaye, Miranda P. 176 Kearney, Philip 47 Kee, Ying Hwa 98 Kegel, Stefan 104 Keith, Sharon E. 188 Keller, Birgit 191 Kello, Christopher T. 9 Kent-Braun, Jane 121 Ketcham, Caroline 66 Kiefer, Adam W. 99 Kiemel, Tim 56 Kim, Sangbum 80 Kim, Seonjin 99 Kim, Wondae 42 Kinrade, Noel P. 177 King, Bradley R. 48, 195 Kingstone, Alan 34 Klein, Kelly 128 Knop, Alexander F. 11 Koceja, David M. 84 Kochi, Naomi 97, 100 Koestner, Richard 169 Kohut, Marian L. 35 Konczak, Jürgen 48, 49, 106 Korff, Thomas 33, 49 Kornatz, Kurt 193 Kossert, Amy L. 177 Kovacs, Attila J. 100, 101, 102, 128 Kowalski, Kent C. 191 Krane, Vikki 210 Kreider, Charlene R. 101 Krug, Jürgen 132 Krüger, Melanie 102, 117, 128
Abstract Author Index S221
Kungl, Ann-Marie 187 Kwan, Matthew Y.W. 178 Kyvelidou, Anastatia 43, 46, 50 Labban, Jeffrey D. 24, 26 Ladewig, Iverson 142 Lafleur, Renée 103 Lai, Shih-Chiung 102 Lajoie, Yves 103 Lam, Melanie Y. 90 Lamarche, Larkin 32, 178 Land, William 179 Latash, Mark L. 90 Latimer, Amy E. 154 Lavoie, Kim L. 192 Lazarus, Jo-Anne C. 51 Le Bars, Hervé 180 LeBlanc, Meghan E. 189 Ledebt, Annick 23, 44, 45 Lee, I Chieh 70, 104 Lee, Irene H. 103 Lee, Jeong Eun 130 Lee, Mei-Hua 51 Lee, Seung-Min 99 Lee, Sunghan 41 Lee, Timothy D. 104 Leißing, Jan 201 Lelièvre, Jonathan 205 Lenoir, Matthieu E.M. 21, 22, 43, 105 Leroux, Mathieu 180 Levin, Mindy F. 134 Lewthwaite, Rebecca 141 Li, Kuan-Yi 106 Liu, Ting 52 Liu, Yeou-Teh 70, 71, 98, 106, 138, 142 Lloyd, Meghann 52 Loberg, Lauren A. 77 Locquet, Claire 181 Lodewyk, Ken 168 Lodha, Neha 107 Loffing, Florian 182 Logan, A. Jane 182, 187 Looper, Julia 40 Lopes, Andrei G. 38 Lorey, Britta 107 Lotz, Simone 85 Loughead, Todd M. 183 Lowry, Kristin A. 35 Lutz, Rafer 183 Lyons, James 81, 119, 196
MacCracken, Mary J. 200 Machida, Moe 63 Mack, Diane E. 173, 191 MacMahon, Clare 108 Macpherson, Alison 37 Magill, Richard A. 96, 120 Major, Samantha C. 172 Malete, Leapetswe 184 Malina, Robert M. 35 Mann, David L. 108 Maraj, Brian 120 Marconi, Nadia F. 79 Markowitz, Ellen S. 209 Martin Ginis, Kathleen A. 148, 149, 150, 159, 185, 189, 202, 214 Martin, James C. 49 Martin, Luc J. 184 Martini, Rose 185 Masellis, Mario 124 Maslovat, Dana 75 Mason, Andrea H. 63, 109 Masters, Rich 122 May, Esther 66 Mayer, Gottfried J. 106 Mayer, Matthew T. 110 Mazala, Davi 54 McBean, Rohan 111 McCardle, Lindsay 185 McDermott, Erin L. 203 McDonough, Meghan H. 164, 186 McGowan, Erin L. 187 McKenna, Jim 37 McLeod, Kelly A. 207 McRobert, Allistair P. 181 Medic, Nikola 208 Meisner, Brad A. 187 Meyer, Ben 110 Moerchen, Vickie 59 Moiseev, Alexander 139 Monsma, Eva V. 188 Montelpare, William J. 37 Mori, Shiro 53 Morris, Tony 122, 135 Morrison, Kyle 39 Morton, Katie L. 188 Motl, Robert W. 131 Mühlbauer, Thomas 102, 117 Mukherjee, Mukul 103 Muller, Sean 111 Mulvey, Genna M. 53, 54
S222 Abstract Author Index
Munroe-Chandler, Krista J. 177, 183, 190 Munzert, Jörn 107, 111 Muon, Sovoeun 189 Murray, Nicholas 112 Murru, Elisa C. 189 Myers, Sara A. 112 Nagano, Tomohisa 93, 113 Naik, Sagar K. 107 Nakamoto, Hiroki 53 Neary, Heather 40 Neely, Kristina A. 113 Nehl, Eric 152 Newell, Karl M. 51, 95, 102, 106, 121 Newstead, Ann H. 33 Ninot, Grégory 180 Norris, Jill M. 162 Norton, Greg 86 Ntoumanis, Nikos 198, 199, 204 O, Jenny 190 Ofori, Edward 114, 115 O’Hara, John 14 Ohgi, Yuji 93 Okazaki, Fabio A. 191 Okun, Morris A. 183 Oleynikov, Dmitry 103 Oliveira, Marcio A. 54, 73 Ong, Nicole T.T. 115 Oster, Kristin G. 173, 191 Oud, William 116 Painter, Richard 116 Pak, Ricky 34 Panchuk, Derek 116 Pang, Samantha 190 Pangelinan, Melissa M. 48, 117, 195 Panzer, Stefan 65, 102, 117 Pappas, George 165 Paquet, Nicole 103 Paquette, Kyle 203 Park, Andrew 118 Parry, Thomas E. 118, 141 Passmore, Steven R. 104, 119 Patterson, Jae T. 127 Pearson, Erin 187 Pelaez, Sandra 192 Pellegrini, Ana M. 44, 55 Pelletier, Chelsea 150 Pelletier, Luc 163
Pelzer, Christie 20 Pena Reyes, Maria E. 35 Perreault, Stéphane 165 Perry, Stephen D. 136 Pettigrew, Christina 140 Pickett, Kristen A. 48, 106 Pilipchuk, Vance 120 Pipinos, Iraklis I. 112 Pirrie, Melissa 168 Polastri, Paula F. 56 Polgar, Jan 210 Popescu, Adrian 120 Porter, Jared M. 120 Posse, Christina G. 80 Poston, Brach 12 Prado, Alexandre K. 38 Prapavessis, Harry 187 Price, Jayme L. 193 Price, Melissa S. 193, 208, 209 Profeta, Vitor L.S. 135 Provasi, Joëlle 38 Ptito, Alain 134 Ranganathan, Rajiv 121 Raudenbush, Bryan 29, 33, 195 Rauff, Erica 194 Raynor, Annette 66 Razuk, Milena 38 Readdick, Christine A. 28 Reed, Alex 33, 195 Remelius, Jebb G. 121 Rendell, Megan 122 Rennie, Mike 111 Rheaume, Nicole L. 123 Rhee, Joohyun 123, 140 Rhodes, Ryan E. 1, 152 Richardson, Gary B. 63 Ridley, David 111 Ridley, Jessica 113 Rietdyk, S. 131 Rietschel, Jeremy C. 195 Riley, Michael A. 127, Ringenbach, Shannon D. 53, 124 Rios-Bedoya, Carlos F. 197 Ripoll, Hubert 181 Robertson, Edwin M. 7 Robinson, Leah E. 45, 56, 57 Roche, Renuka 57 Rootes, Brad 203 Rose, Matthew 111
Abstract Author Index S223
Ross, Emma Z. 150 Roth, Stephen 214 Rotteau, Thea O. 81, 196 Roy, Eric A. 110, 116, 124 Rudisill, Mary E. 57 Runnalls, Keith 120 Russell, Daniel M. 101 Russell, Kelly L. 196 Russell, Shawn D. 62 Rymal, Amanda M. 174 Sabiston, Catherine M. 156, 174 Saffer, Mark I. 124 Safir, Oleg 125 Sage, Michael D. 110, 125 Samson, Jean M. 13, 126, 131 Sanderson, David J. 69 Sanli, Elizabeth 127 Santiago, Olga J. 197 Saunders, Nichole E. 127 Savelsbergh, Geert J.P. 23, 44, 45, 105 Sayles, Julia K. 203 Schack, Thomas 151 Schiphof, Lieke 197 Schleihauf, Robert C. 38 Schmidt, Maike 68 Schoch, Beate 49 Schorer, Jörg R. 14, 15, 85, 198 Schott, Nadja 11, 12 Schücker, Linda 85 Schultheis, Maria T. 130 Seefeldt, Vern 39 Seong, Younho 28 Serene, Nicole 206 Shapcott, Kim 187 Shaw, Sally 146 Shea, Charles H. 65, 68, 100, 101, 102, 117, 128 Shea, John B. 28, 110, 118, 141 Sherwood, David E. 128, 129 Shewokis, Patricia A. 130 Shields, Chris A. 154 Shim, Jae Kun 31, 54, 73 Shim, Jaeho 130 Shin, Sunghoon 131 Shockley, Kevin 20, 99 Shostrom, Valerie K. 50 Sidaway, Ben 101 Silver, Tobin A. 131 Simon, Christopher R. 34
Sinnett, Scott 34 Siu, Ka-Chun 103 Slater, Karen 30 Smiley-Oyen, Ann L. 35 Smith, Alan L. 164 Smith, Alison L. 198, 199 Smith, Allison 20 Smith, Beth A. 58, 59 Smith, Peter J. 132 Smyth, Patrick J. 47 Snapp-Childs, Winona 58 Snook, Erin M. 131 Sonnadara, Ranil 81 Sosnoff, Jacob J. 13, 36, 114, 115, 126, 131 Soukup, Gregory J. 200 Spaulding, Sandi J. 136 Spink, Kevin S. 156, 168, 211, 212 Spray, Chris M. 204 Springs, Sherry 28 Stadulis, Robert E. 200 Stamenova, Vessela 116, 124 Standage, Martyn 204 Stanley, Damian M. 201 Stark, Rudolf 107 Starkes, Janet L. 208 Staudinger, Ursula M. 36 Stelmach, George E. 12 Ste-Marie, Diane M. 174, 185 Stergiou, Nicholas 43, 46, 50, 58, 92, 97, 100, 103, 112 Stevens, Jessica 45 Stöckel, Tino 132 Stoffregen, Thomas A. 19, 20, 21 Strachan, Shaelyn M. 175 Strang, Adam J. 133 Strauss, Bernd 85, 182, 201 Streeter, Ryan 38, 137 Strong, Heather A. 189, 202 Stuberg, Wayne A. 43, 50 Studenka, Breanna E. 133 Stuntz, Cheryl P. 203 Subramanian, Sandeep 134 Sullivan, Philip J. 164, 184, 203 Sullivan, Katherine J. 81, 97 Swan, Kristin M. 68 Symons Downs, Danielle A. 194 Tamminen, Katherine A. 186, 204 Tan, Swee Kheng 35
S224 Abstract Author Index
Tangsilsat, Supatchara E. 207 Taylor, Ian M. 204 Tenenbaum, Gershon 179 Teulier, Caroline 59 Thanikkal Kottayil, Soni John 135 Théoret, Hugo 8 Thomas, Kathleen S. 60 Thompson, Amanda S. 205 Tijtgat, Pieter T. 105 Till, Kevin 14 Timmann, Dagmar 49 Timmis, Matthew 88 Tobar, David A. 206 Torre, Kjerstin 9, 10 Torres-McGehee, Toni 188 Turvey, Michael T. 65 Ugrinowitsch, Herbert 78, 135, 137 Ullrich-French, Sarah C. 206 Ulrich, Beverly D. 23, 54, 58, 59 Ulrich, Dale A. 40, 52 Underhill, Alycia 82 Vaculin, Amber 140 Valdez, Andre B. 136 Van der Kamp, John 95 Van Donkelaar, Paul 7 Van Emmerik, Richard E.A. 87, 88, 121 Van Gemmert, Arend W.A. 12 Van Kampen, Paulien M. 23 Van Oostveen, Rachel B. 136 Vander Velden, Heidi 48 Vansteenkiste, Maarten 199 Verheul, Martine H.G. 44 Vickers, Joan N. 116 Vieira, Márcio M. 137 Virji-Babul, Naznin 90, 139 Virtanen, Petri P. 94 Vlasic, Joshua 61 Voelcker-Rehage, Claudia 11, 36 Völker, Klaus 85 Voudrie, Stefani J. 13, 36, 131 Wade, Michael G. 19, 20, 69 Wagenmakers, Eric-Jan 10 Wagoner, Kent 31 Wallace, Stephen 137 Wang, Ning 138 Wattie, Nick 14, 16, 37 Webb, Heather E. 207
Webb, Oliver J. 207 Webster, Andrew 29 Weeks, Daniel 139 Weigelt, Matthias 56, 132 Weir, Patricia L. 187, 208 Weiss, Maureen R. 193, 208, 209 Welsh, Timothy N. 6 Wershing, Ben 33 Wesch, Natascha N. 210 Whaley, Diane E. 210 Whitaker, Laura L. 78 Whitall, Jill 2, 54, 57 Whittaker, Carly S. 211, 212 Williams, A. Mark 17, 29, 181 Williams, Andrew M. 139 Willow, Jason P. 211 Wilms-Floet, Anna Maria 57 Wilson, Brian 19 Wilson, Kathleen S. 211, 212 Wilson, Philip M. 172, 173, 189, 191 Wiman, Melissa 212 Winstein, Carolee J. 81 Wong, Harmonie R. 213 Woo, Minjung 214 Woodgate, Jennifer 214 Woods, Jeffrey A. 114 Wright, David L. 123, 140 Wright, Michael J. 61 Wulf, Gabriele 140, 141 Wyatt, William R. 118, 141 Yamaguchi, Andrea Y.S. 142 Yang, Lian-Zong 70 Yen, Ya-Ting 106 Yin-Hua, Chen 142 Yook, Dong Won 130 Yoshida, Ken 20, 21 Young, Greg 143 Zaal, Frank 143 Zeglen, Laura 172 Zelaznik, Howard N. 123, 133 Zentgraf, Karen 107 Zhuang, Guo-Liang 70 Zihlman, Kirk A. 123 Zimmermann, Cris 107 Zoudji, Bachir 181
