Object representations for multiple visual categories overlap in lateral occipital and medial fusiform cortex

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Serval ID
serval:BIB_9DE13746CAE1
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Object representations for multiple visual categories overlap in lateral occipital and medial fusiform cortex
Journal
Cerebral Cortex (new York, N.y. : 1991)
Author(s)
Pourtois G., Schwartz S., Spiridon M., Martuzzi R., Vuilleumier P.
ISSN
1460-2199 (Electronic)
ISSN-L
1047-3211
Publication state
Published
Issued date
2008
Volume
19
Number
8
Pages
1806-1819
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Abstract
How representations of visual objects are maintained across changes in viewpoint is a central issue in visual perception. Whether neural processes underlying view-invariant recognition involve distinct subregions within extrastriate visual cortex for distinct categories of visual objects remains unresolved. We used event-related functional magnetic resonance imaging in 16 healthy volunteers to map visual cortical areas responding to a large set (156) of exemplars from 3 object categories (faces, houses, and chairs), each repeated once after a variable time lag (3-7 intervening stimuli). Exemplars were repeated with the same viewpoint (but different retinal size) or with different viewpoint and size. The task was kept constant across object categories (judging items as "young" vs. "old"). We identified object-selective adaptation effects by comparing neural responses to the first presentation versus repetition of each individual exemplar. We found that exemplar-specific adaptation effects partly overlapped with regions showing category-selective responses (as identified using a separate localizer scan). These included the lateral fusiform gyrus (FG) for faces, parahippocampal gyrus for houses, and lateral occipital complex (LOC) for chairs. In face-selective fusiform gyrus (FG), adaptation effects occurred only for faces repeated with the same viewpoint, but not with a different viewpoint, confirming previous studies using faces only. By contrast, a region in right medial FG, adjacent to but nonoverlapping with the more lateral and face-selective FG, showed repetition effects for faces and to a lesser extent for other objects, regardless of changes in viewpoint or in retinal image-size. Category- and viewpoint-independent repetition effects were also found in bilateral LOC. Our results reveal a common neural substrate in bilateral LOC and right medial FG underlying view-invariant and category-independent recognition for multiple object identities, with only a relative preference for faces in medial FG but no selectivity in LOC.
Keywords
Occipital Lobe/physiology, Parahippocampal Gyrus/physiology, Temporal Lobe/physiology, Visual Perception/physiology
Pubmed
Web of science
Open Access
Yes
Create date
13/07/2018 10:00
Last modification date
14/02/2022 8:56
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