Where is it? What is it? and What's going on?!

Or... Differential parahippocampal and retrosplenial involvement
in three types of visual scene recognition

Russell A. Epstein & J. Stephen Higgins
Department of Psychology and Center for Cognitive Neuroscience
University of Pennsylvania
In press, Cerebral Cortex
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Human observers can quickly and accurately interpret the meaning of complex visual scenes. The neural mechanisms underlying this ability are largely unexplored. We used functional magnetic resonance imaging (fMRI) to measure cortical activity while subjects identified briefly-presented scenes as either specific familiar locations ("Houston Hall"), general place categories ("kitchen"), or general situational categories ("party"). Scene responsive voxels in the parahippocampal place area (PPA) and retrosplenial cortex (RSC) were highly sensitive to recognition level when identifying scenes, responding more strongly during location identification than during place category or situation identification. In contrast, the superior temporal sulcus, cingulate sulcus, and supermarginal gyrus displayed the opposite pattern, responding more strongly during place category and situtation identification. Consideration of results from four experiments suggest that the PPA represents the visuospatial structure of individual scenes, while RSC supports processes that allow scenes to be localized within a larger
extended environment. These results suggest that different scene identification tasks tap distinct cortical networks. In particular, we hypothesize that the PPA and RSC are critically involved in the identification of specific locations but play a less central role in other scene recognition tasks.