Three cortical scene systems and their development

Since the discovery of three scene-selective regions in the human brain, a central assumption has been that all three regions directly support navigation. We propose instead that cortical scene processing regions support three distinct computational goals (and one not for navigation at all): (i) The parahippocampal place area supports scene categorization, which involves recognizing the kind of place we are in; (ii) the occipital place area supports visually guided navigation, which involves finding our way through the immediately visible environment, avoiding boundaries and obstacles; and (iii) the retrosplenial complex supports map-based navigation, which involves finding our way from a specific place to some distant, out-of-sight place. We further hypothesize that these systems develop along different timelines, with both navigation systems developing slower than the scene categorization system. It is widely believed that cortical scene processing in adult humans – composed of the parahippocampal place area (PPA), the occipital place area (OPA), and the retrosplenial complex (RSC) – is wholly devoted to navigation.Challenging this pervasive theory, recent research suggests that the PPA is not involved in navigation but instead is involved in ‘scene categorization.’By contrast, the OPA and RSC are involved in navigation, albeit different kinds (i.e., ‘visually guided navigation’ and ‘map-based navigation,’ respectively).Thus, we propose that adult human cortical scene processing comprises three dissociable systems.Furthermore, we propose that the PPA, OPA, and RSC develop along different timelines, and we offer the specific hypothesis that both the visually guided navigation and map-based navigation systems are slower to develop than the scene categorization system.