Distributed cortical regions for the recall of people, places and objects

Abstract

Human medial parietal cortex (MPC) is recruited during multiple cognitive processes. Previously, we demonstrated regions specific to recall of people or places and proposed that the functional organization of MPC mirrors the category selectivity defining the medial-lateral axis of ventral temporal cortex (VTC). However, prior work considered recall of people and places only and VTC also shows object-selectivity sandwiched between face- and scene-selective regions. Here, we tested a strong prediction of our proposal: like VTC, MPC should show a region specifically recruited during object recall, and its relative cortical position should mirror the one of VTC. While responses during people and place recall showed a striking replication of prior findings, we did not observe any evidence for object-recall effects within MPC, which differentiates it from the spatial organization in VTC. Importantly, beyond MPC, robust recall-effects were observed for people, places, and objects on the lateral surface of the brain. Place-recall effects were present in the angular gyrus, frontal eye fields and peripheral portions of early visual cortex, whereas people-recall selectively drove response in the right posterior superior temporal sulcus. Object-recall effects were largely restricted to a region posterior to left somatosensory cortex, in the vicinity of the supramarginal gyrus. Taken together, these data demonstrate that while there are distributed regions active during recall of people, places and objects, the functional organization of MPC does not mirror the medial-lateral axis of VTC but reflects only the most salient features of that axis - namely representations of people and places. Significance statementHuman medial parietal cortex (MPC) is recruited during multiple cognitive processes. Recently, we proposed a framework for interpreting the functional organization of MPC by suggesting that it reflects the categorical preferences for people and places that is evident also in ventral temporal cortex (VTC). Because VTC also exhibits selectivity for objects, we here extend this framework to test whether MPC also shows object selectivity during recall. Robust people and place recall effects were evident in MPC, but we found no evidence for object-recall within MPC, suggesting that MPC and VTC are not mirror-copies of each other. Together, these data suggest that the functional organization of MPC reflects the most salient categorical representations within VTC for people and places.