Spatial tuning of face part representations within face-selective areas revealed by high-field fMRI.

Jiedong Zhang,Yong Jiang,Yunjie Song,Peng Zhang,Sheng He

doi:10.7554/elife.70925

Abstract

Regions sensitive to specific object categories as well as organized spatial patterns sensitive to different features have been found across the whole ventral temporal cortex (VTC). However, it is unclear that within each object category region, how specific feature representations are organized to support object identification. Would object features, such as object parts, be represented in fine-scale spatial tuning within object category-specific regions? Here, we used high-field 7T fMRI to examine the spatial tuning to different face parts within each face-selective region. Our results show consistent spatial tuning of face parts across individuals that within right posterior fusiform face area (pFFA) and right occipital face area (OFA), the posterior portion of each region was biased to eyes, while the anterior portion was biased to mouth and chin stimuli. Our results demonstrate that within the occipital and fusiform face processing regions, there exist systematic spatial tuning to different face parts that support further computation combining them.

Highlights

The ventral temporal cortex (VTC) in the brain supports our remarkable ability to recognize objects rapidly and accurately from the visual input in everyday life
mid-fusiform sulcus (MFS) is found to be highly consistent with many anatomical lateral-m edial transitions in the VTC, such as cytoarchitecture and white-matter connectivity transitions (Weiner et al, 2014; Caspers et al, 2013; Grill-Spector and Weiner, 2014; Lorenz et al, 2017)
Considering its anatomical and functional significance, in the current study, we used the direction of MFS to align the potential spatial tuning of face part across individuals

Summary

Introduction

The ventral temporal cortex (VTC) in the brain supports our remarkable ability to recognize objects rapidly and accurately from the visual input in everyday life. Numerous studies have already revealed multiple levels of feature representation manifest at different scales of anatomical organizations which superimposed in the VTC. The category-selective representations (e.g. face, body, and scene selective regions in the mid-fusiform gyrus) are revealed at finer spatial scale in the VTC (Hasson et al, 2003; Spiridon et al, 2006). Recent evidence suggested a general spatial organization of neural responses to dimensions in object feature space in monkey inferotemporal cortex (Bao et al, 2020). Could such physical organization be further extended to even smaller scale, like object parts/features representations within each category-selective region? Could such physical organization be further extended to even smaller scale, like object parts/features representations within each category-selective region? In other words, as

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Conclusion