Papers 222 - 225
Saturday Afternoon
a MPT model. The new MPT model is called the Perceptual Detection (PD) model, and it is an adaptation of the Chechile (2004) 6P memory model. The key properties of the model are developed, and applied to the case of a radiologist examining CT scans. The PD model brings out novel features that were absent from the standard SD analysis. Email: Richard Chechile,
[email protected]
cotermination, and parallelism. Overall, changes in NAPs were detected faster than metric changes, while position and orientation changes in junctions were not always as predicted by MMT. Email: Johan Wagemans,
[email protected] 2:50-3:05 (224) Aesthetic Preferences for Spatial Compositions: Evaluating the Rule of Thirds. STEPHEN PALMER, JAN FLATLEYFELDMAN, YURIKA S. HARA and WILLIAM S. GRISCOM, University of California, Berkeley. — The Rule of Thirds posits that, regardless of the image content, the best positions for a focal object within an image lie along the vertical and horizontal third-lines, yielding the best compositions when the object is located at one of their four intersections and the worst compositions when it is at the frame’s center. Our results strongly contradict all of these predictions. Forward-facing objects produced a powerful center bias, whereas left-facing and right-facing objects produced an inward bias, being preferred off-center but only when there is more space in front than behind the object. We hypothesized that these biases might arise simply from a bias toward centered placement of an object’s affordance space: its perceived functional surrounding space that includes room for its interactions with observers and other objects (e.g., extending farther in front than behind for most objects). An empirical test was consistent with this possibility: 2AFC judgments of affordance-space structure were highly consistent with 2AFC judgments of aesthetic preference in composition for corresponding pictures of the same objects (r = ~.80) and much less consistent with the predictions of the Rule of Thirds. Email: Stephen Palmer,
[email protected]
2:10-2:25 (222) Increased Alpha Band Activity Indexes Inhibitory Competition Across a Border During Figure Assignment. MARY PETERSON and JOSEPH L. SANGUINETTI, University of Arizona, LOGAN T. TRUJILLO and DAVID M. SCHNYER, University of Texas, Austin, JOHN J.B. ALLEN, University of Arizona. — Increased EEG alpha band activity may index inhibition of task-irrelevant information. Here, we test whether increased alpha activity indexes inhibitory competition for figural status. In 3 experiments, participants judged silhouettes as “real-world” or “novel” objects. Real-world silhouettes depicted namable objects. Novel silhouettes depicted novel objects on the inside, figure-side, of their borders. There were 2 types of novel silhouettes: High-competition (HC) novel silhouettes, where real-world objects suggested on the outside of the borders competed with the inside for figural status; and low competition (LC) novel silhouettes where little competition occurred. In Experiments 1-2 alpha power was greater for HC than LC, p < .05; repetition lag (many items) had no effect. In Experiment 3, with short lags (4-7 items, ~10s), alpha power was reduced for 2nd versus 1st presentation of HC only, p < .05, suggesting that persisting inhibition of the object suggested on the groundside reduced competition on second presentation. Therefore, EEG alpha band activity increases with increased inhibitory competition for figure assignment. These results are consistent with the view that alpha indexes inhibition. Email: Mary Peterson,
[email protected]
3:10-3:25 (225) Visual Cues Effects on Temperature Perception. CARRIE ANNE BALCER, ANDREW SHIRTZ, TAYLOR ROLISON and MOUNIA ZIAT, Northern Michigan University (Presented by Mounia Ziat). — The purpose of this study is to understand multisensory integration between the color and the temperature of an object when a conflict arises. It was hypothesized that when the information of color and temperature stimuli are incongruent (blue-warm or redcold), reaction times (RTs) will be slower than when they are congruent (blue-cold or red-warm). We utilized the Oculus Rift, a head-mounted display to create a virtual environment that allowed us to control color cues of cup’s temperature and a Peltier thermo-device to provide tactile temperature stimuli. The results confirmed our initial expectation, as suggested by longer RTs for incongruent stimuli. The results also showed that participants rated cold temperature sensations warmer when presented simultaneously with a visual red color cue and warm temperature sensations cooler when presented simultaneously with a visual blue color cue. Email: Mounia Ziat,
[email protected]
2:30-2:45 (223) Sensitivity to Nonaccidental Properties in Two-Line Configurations. JOHAN WAGEMANS, CHARLOTTE SLEURS and JONAS KUBILIUS, University of Leuven (KU Leuven). — Why do some pairs of short line segments look special and others random? Minimal Model Theory (MMT) holds that two-line configurations are more special if there are fewer degrees of freedom left to change their relative position and orientation. Another theory emphasizes the role of nonaccidental properties (NAPs) that allow 3D shape recovery. Predictions from both theories were tested in three experiments with displays consisting of four two-line configurations, three identical and one different, which had to be located. The odd one out differed from the others by a change in angle or position (e.g., from T- to L- or X-junction) in two experiments. In Experiment 3, metric changes were directly compared to changes in NAPs such as collinearity,
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