Abstract
High-level visual cortex contains regions that selectively and differentially process certain categories, such as words, scenes and faces, but little is known about how they are optimized to support such processing. Here, using a population receptive field (pRF) model that allows for estimates of elliptical and orientated pRFs, we show that two regions, the visual word form area (VWFA) and parrahippocampal place area (PPA), which subserve word reading and scene processing, respectively, integrate information across visual space in vastly different ways, each optimized to support their preferred category. Eighteen participants completed pRF mapping experiments and category-selective functional localizers. A combination of group-based and individual participant data was used to define VWFA, whereas PPA was defined in each individual. Word-selective cortex VWFA contained pRFs that were simultaneously foveal, elliptical, and predominantly horizontal, the ideal parameters for recognizing word forms, whilst those in scene-selective PPA were peripheral, more circular, and more broadly tuned in orientation. Importantly, these pRF patterns also differ from those observed in early visual cortex, highlighting different processing mechanisms between low- and high-level visual regions. These differing patterns of pRF properties suggest that high-level visual cortex is fundamentally optimized to support the processing of specific visual categories through the differential integration of information across visual space.
Meeting abstract presented at VSS 2018