Abstract
Previous work has shown that retrosplenial cortex (RSC) is implicated in scene integration of multiple views. The current research investigates the role of category information in scene integration and its behavioral consequences. Using statistical regularities in temporal context, we have shown that RSC responds significantly greater to a repeated scene exemplar if the preceding context provides information about a scene category (VSS 2016). For example, upon presenting an image sequence of MountainA-WaterfallA-BeachA, and later MountainB-WaterfallB-BeachA (category-context condition), RSC responds significantly greater to the repetition of BeachA. This effect was not present when the temporal context didn't contain repeated category information (novel-context condition, e.g. MountainA-WaterfallA-BeachA and DesertA-ForestA-BeachA). Here we test two possible interpretations of the above result using fMRI and behavioral experiments. In the first experiment, we test whether the repetition enhancement of RSC is due to a carryover effect from the preceding context. When we replaced the third item (e.g., BeachA with BeachB) while keeping preceding context the same (e.g., Mountain-Waterfall), RSC no longer showed greater activation for the third item, suggesting that this was not due to carryover. In the second experiment, we hypothesize that if category information in temporal contexts work as a cue for integration, then different scene images that were grouped in temporal context should be judged as more similar to each other. In a behavioral experiment (N=23), participants were exposed to images in one of two conditions while performing an indoor-outdoor decision task: Category-context or Novel-context conditions. Afterwards, they were given a surprise same-different task on pairs of images (e.g., MountainA vs MountainB). We found that participants in the Category-context condition were significantly slower to respond "different" to the pair than participants in the Novel-context condition. This finding indicates that perceptual similarity of scenes increases when they are grouped within the same temporal context.
Meeting abstract presented at VSS 2017