The Emergence of Topography and Hemispheric Lateralization in High-Level Vision

This article reviews research that examines the topographic organization of the human brain, the role of development, breakdown and plasticity, and the constraints that give rise to the replicable organization across individuals and cultures. To address these questions, we evaluate the topographic arrangement of regions in ventral temporal cortex (VTC) that respond strongly to the viewing of faces and words, and demonstrate that both categories drive responses in both hemispheres albeit to a greater degree in the right hemisphere for faces and left hemisphere for words. We hypothesize that this weighted asymmetric topography emerges over the course of development, and we instantiate the hypothesis within a computational model and confirm predictions of this account with evidence from normal and impaired behavior and from neuroimaging. We also confront challenges to a particular component of this account, namely, the status of the local competition between word and face representations in VTC, and we go on to describe an expanded perspective with additional empirical data and a more complex computational framework, which highlights the generality of both local and long-range constraints on the emergence of within- and between-hemisphere topographic organization. Together, these findings offer a framework in which topographic organization emerges through an optimization process constrained by biological connectivity, the nature of the visual representations and development.