Object Domain and Modality in the Ventral Visual Pathway

The nature of domain-specific organization in higher-order visual cortex (ventral occipital temporal cortex, VOTC) has been investigated both in the case of visual experience deprivation and of modality of stimulation in sighted individuals. Object domain interacts in an intriguing and revelatory way with visual experience and modality of stimulation: selectivity for artifacts and scene domains is largely immune to visual deprivation and is multi-modal, whereas selectivity for animate items in lateral posterior fusiform gyrus is present only with visual stimulation. This domain-by-modality interaction is not readily accommodated by existing theories of VOTC representation. We conjecture that these effects reflect a distinction between the visual features that characterize different object domains and their interaction with different types of downstream computational systems.

TrendsA wave of recent studies has reported similar domain preference effects in ventral occipital temporal cortex (VOTC) in sighted and congenitally blind individuals, leading to the contention that object representation in this region is multi-modal.However, the effects of visual deprivation on object category selectivity paint an intriguing pattern of heterogeneity: selectivity to spatial navigation stimuli and manipulable artifacts found to be robustly multi-modal, whereas selectivity to animate objects reliably present only for sighted individuals when processing visual stimuli.We formulate a novel conjecture about the nature of representations in VOTC: representation types are partly driven by the nature of the mapping between object visual properties and other object properties, which differ between animate and inanimate objects.