Different roles of the parahippocampal place area (PPA) and retrosplenial cortex (RSC) in panoramic scene perception

Constructing a rich and Continuous Visual experience requires computing specific details across views as well as integrating similarities across views. In this paper, we report functional magnetic resonance imaging (fMRI) evidence that these distinct computations may occur in two scene-sensitive regions in the brain, the parahippocampal place area (PPA) and retrosplenial cortex (RSC). Participants saw different snapshot views from panoramic scenes, which represented clearly different views, but appeared to come from the same scene. Using fMRI adaptation, we tested whether the PPA and RSC treated these panoramic views as the same or different. In the panoramic condition, three different views from a single panoramic scene were presented. We did not find any attenuation for panoramic repeats in the PPA, showing viewpoint-specificity. In contrast, RSC showed significant attenuation for the panoramic condition, showing viewpoint-integration. However, when the panoramic views were not presented in a continuous way, both the specificity in the PPA and the integration in RSC were lost. These results demonstrate that the PPA and RSC compute different properties of scenes: the PPA focuses on selective discrimination of different views while RSC focuses on the integration of scenes under the same Visual context. These complementary functions of the PPA and RSC enable both specific and integrative representations of scenes across several viewpoints. (C) 2009 Elsevier Inc. All rights reserved.