The cortical basis of visual scene processing

Several lines of evidence suggest that the human brain contains special-purpose machinery for processing information about visual scenes. In particular, a region in medial occipitotemporal cortex—the “parahippocampal place area”, or PPA—represents the geometric structure of scenes as defined primarily by their background elements. Neuroimaging studies have demonstrated that the PPA responds preferentially to scenes but not to the objects within them, while neuropsychological studies have shown that damage to this region leads to an impaired ability to learn new scenes. More recent evidence suggests that the PPA encodes novel scenes in a viewpoint-specific manner and that these codes are more reliable in good navigators than bad navigators. The PPA may be part of a larger network of regions involved in processing navigationally relevant spatial information. The role of this region in place recognition and gist comprehension is also discussed.