RESUMEN
The perception of a visual stimulus is dependent not only upon local features, but also on the arrangement of those features. When stimulus features are perceptually well organized (e.g., symmetric or parallel), a global configuration with a high degree of salience emerges from the interactions between these features, often referred to as emergent features. Emergent features can be demonstrated in the Configural Superiority Effect (CSE): presenting a stimulus within an organized context relative to its presentation in a disarranged one results in better performance. Prior neuroimaging work on the perception of emergent features regards the CSE as an "all or none" phenomenon, focusing on the contrast between configural and non-configural stimuli. However, it is still not clear how emergent features are processed between these two endpoints. The current study examined the extent to which behavioral and neuroimaging markers of emergent features are responsive to the degree of configurality in visual displays. Subjects were tasked with reporting the anomalous quadrant in a visual search task while being scanned. Degree of configurality was manipulated by incrementally varying the rotational angle of low-level features within the stimulus arrays. Behaviorally, we observed faster response times with increasing levels of configurality. These behavioral changes were accompanied by increases in response magnitude across multiple visual areas in occipito-temporal cortex, primarily early visual cortex and object-selective cortex. Our findings suggest that the neural correlates of emergent features can be observed even in response to stimuli that are not fully configural, and demonstrate that configural information is already present at early stages of the visual hierarchy.
RESUMEN
Food sharing may be used for mate attraction, sexual access, or mate retention in humans, as in many other species. Adult humans tend to perceive more intimacy in a couple if feeding is observed, but the increased perceived intimacy may be due to resource provisioning rather than feeding per se. To address this issue, 210 university students (66 male) watched five short videos, each showing a different mixed-sex pair of adults dining together and including feeding or simple provisioning or no food sharing. A survey concerning attraction and intimacy in the dyad was completed after each video. Both provisioning and feeding produced higher ratings of "Involvement," with feeding producing the highest ratings. Similarly, the perceived attraction of each actor to the other was lowest when no food sharing was shown and highest when feeding was displayed. These findings are consistent with a view of feeding as a courtship display in humans.