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10 participants from group with stable representation (2 male, 8 female) took part in an eye-tracking research 4 months later than the main experiment. Participants performed the same forced choice recognition tasks as before: 35 pictures were displayed on the monitor, each for 1 sec. and followed by a mask. Participants indicated if the picture was familiar from previous stage of research or not, then next picture was presented. In the end participants were told, that they would be shown the correct answers and they were shown the initial 8 pictures. Every picture was shown for 1 sec. We expected that the second view of the same picture would reveal more fixations of same objects when an embarrassing picture is correctly recognized in comparison to misses and correctly rejected neutral pictures. Average number of fixations per picture was 2.9. Wilcoxon statistics was used. Assumption was confirmed partly. There are significantly more fixations of the same objects in first and second presentation of the correctly recognized embarrassing pictures, than when they don’t recognize embarrassing (р = .043) and neutral (p= .009) pictures. But there are no significant differences in re-fixations when
participants correctly recognize embarrassing and neutral pictures and when they correctly recognize and don’t recognize neutral pictures. Nevertheless this data allow saying that people with stable attitude toward their reaction in embarrassing situations examine them in another way, than situations without such attitude. Our results suggest that people’s thinking about their response in such situations is important for their perception of them. People with stable representations of what situations evoke their avoidance, recognize such situations more precisely than other situations and more precisely than people without such representation. They understand and control emotions of others worse and examine embarrassing situations in another way, than other situations. People with unstable representation divide situations into embarrassing and not, but they don’t differ from both other groups in characteristics of their perception. * According to Flavell metacognitive knowledge is one's stored knowledge or beliefs about oneself and others as cognitive agents, about tasks, about actions or strategies, and about how all these interact to affect the outcomes of any sort of intellectual enterprise.
PERCEPTUAL SPACE OF NATURALLY EXPRESSED EMOTIONS: A PROPOSED STUDY Olga A. Kurakova
[email protected] Center for Experimental Psychology, Moscow City University for Psychology and Education (Russia) Categorical perception effect refers to the phenomenon that objects perceived as belonging to different perceptual categories are easier to discriminate between than those from the same category even if they have equal physical distances (Harnad, 1987). This effect has been investigated in different types of objects (e.g., color) by varying their physical characteristic (e.g., wavelength) linearly and asking subjects to name the stimuli (e.g., hues) and discriminate between them. Recent ERP (event-related potentials) studies (Campanella et al., 2002) have shown that categorical perception effect of morphed emotional facial expressions (FE), previously found in a number of behavioral studies (Etcoff, Magee, 1992; Calder et al., 1996; Bimler, Kirkland, 2001), can also be obtained by
measuring amplitudes of the N170 ERP component. Bilateral occipito-temporal N170 is known to be significantly larger to faces than to non-faces (Bentin et al., 1996) and probably to emotional faces rather than to non-emotional ones (Batty, Taylor, 2003; Blau et al., 2007). Though, the reported results of both electrophysiological and behavioral studies can be put into question by reasons of methodology, the most crucial of that is applying of computer morphing procedure to the pictures of FE to acquire sequences of transitional images between them that appear to be artificial and lack ecological validity. Morphs, which are used widely to explore mechanisms of FE perception, cannot represent correctly neither trajectories of natural facial muscles movements nor dynamics of expressions. As faces comprise a category of natural objects that can vary their exact form (by facial muscles activity) rather widely but limited to certain muscular capabilities, it seems essential to use as stimuli natural expressions instead of artificial ones. Such an attempt was made in (Schiano, 2004), but only on the basis of behavioral data, and categorical perception
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effect was not found. We expect that ERP method can be useful in studying this question. The aim of the proposed study is to reveal the structure of perceptual space of naturally expressed transitions between basic FE using both behavioral and electrophysiological methods. To obtain this, we will use taken with high-speed (up to 300 frames per second) camera photographs of actors expressing basic FE (6 emotions + neutral, as described in Ekman, Friesen, 1978) and all possible transitions between them. High speed is crucial for our purposes, because transitions between FE could last dozens of milliseconds or even less. Neutral to emotion transitions will give us the dynamics of certain FE generated and transitions from one emotion into another - dynamics of switching between them. The physical interstimuli differences will then be measured and equidistant image sequences chosen to control the independent variable in behavioral and reaction time (RT) identification and
A X discrimination B
tasks (where X stands for
either A or B; A, B – stimuli presented simultaneously to avoid memory load that occurs in classical ABX sequential task and can influence the performing). Several series with varying stimuli presentation times (100 ms, 200 ms, 3 s) will be held. The boundaries between the categories will be defined between two consequent frames showing best and fastest discrimination. Then pairs of pictures that (a) cross the boundaries, (b) fall into the same category and (c) identical pictures for methodological purposes will be used as between-category, within-category and same conditions stimuli in electrophysiological experiment with same-different task. We hypothesize that: (1) natural expressions space based on identification and discrimination tasks results would have categorical structure; (2) the boundary between emotional categories in such space would vary depending on presentation time; (3) N170 amplitude would be larger to between-category pairs of stimulus than to within-category ones; (4) spaces based on behavioral and physiological data would show similar structure. The results of the proposed study can be of both theoretical and practical value. They would make for theoretical understanding and conceptualization of face and FE perception. Our
predictions, if correct, would also contribute to exploring the overall emotion perception and production mechanisms. As concluded in (Murphy et al., 2003) metaanalysis of 106 fMRI and PET studies, particular emotional programs do have different brain mapping patterns. This finding can be a strong evidence of separate mechanisms for basic emotions. Categorical effect is considered to be an indirect marker of the same statement. Indeed, if proved on the full set of natural FE, the modulation of ERP component by crossing category boundary can provide us with better understanding of emotional brain systems functioning. Работа выполнена при финансовой поддержке Роснауки ГК № 02.740.11.0420 «Организация и динамика познавательных процессов в условиях общения и совместной деятельности». Batty M., Taylor M. J. (2003). Early processing of the six basic facial emotional expressions. Brain research. Cognitive brain research, 17 (3), 613–620. Bentin S., Allison T., Puce A., Perez E., McCarthy G. (1996). Electrophysiological studies of face perception in humans. Journal of Cognitive Neuroscience, 8 (6), 551–565. Bimler D., Kirkland J. (2001). Categorical perception of facial expressions of emotion: Evidence from multidimensional scaling. Cognition and Emotion, 15 (5), 633–658. Blau V. C., Maurer U., Tottenham N., McCandliss B. D. (2007). The face-specific N170 component is modulated by emotional facial expression. Behavioral and brain functions, 3 (7). Calder A. J., Young A. W., Perrett D. I., Etcoff N. L., Roland D. (1996). Categorical Perception of Morphed Facial Expressions. Visual Cognition, 3 (2), 81–117. Campanella S., Quinet P., Bruyer R., Crommelinck M., Guerit J. M. (2002). Categorical perception of happiness and fear facial expressions: an ERP study. Journal of cognitive neuroscience, 14 (2), 210–227. Ekman P., Friesen W. (1978). Facial action coding system. Palo Alto: Consulting psychologists Press. Etcoff N. L., Magee J. J. (1992). Categorical perception of facial expressions. Cognition, 44, 281–295. Harnad S. (1987). Introduction: Psychophysical and cognitive aspects of categorical perception: A critical overview. S. Harnad (ed.) Categorical perception: The groundwork of cognition. Cambridge: Cambridge University Press. Murphy F. C., Nimmo-Smith I., Lawrence A.D. (2003). Functional neuroanatomy of emotions: a metaanalysis. Cognitive, Affective and Behavioral Neuroscience, 3 (3), 207–233. Schiano D. J., Ehrlich S.M., Sheridan K. Categorical imperative not: facial affect is perceived continuously // CHI 2004, N.Y.: ACM, 2004, pp. 49-56.
