Visual object agnosia is associated with a breakdown of object-selective responses in the lateral occipital cortex

Ptak, Radek; Lazeyras, François; Di Pietro Peralta-Bachman, Marie; Schnider, Armin; Simon, Stéphane

doi:10.1016/j.neuropsychologia.2014.05.009

Scientific article

English

Visual object agnosia is associated with a breakdown of object-selective responses in the lateral occipital cortex

Contributors

Ptak, Radek

; Lazeyras, François; Di Pietro Peralta-Bachman, Marie; Schnider, Armin; Simon, Stéphane

Published in

Neuropsychologia, vol. 60, p. 10-20

Publication date

2014

Abstract

Patients with visual object agnosia fail to recognize the identity of visually presented objects despite preserved semantic knowledge. Object agnosia may result from damage to visual cortex lying close to or overlapping with the lateral occipital complex (LOC), a brain region that exhibits selectivity to the shape of visually presented objects. Despite this anatomical overlap the relationship between shape processing in the LOC and shape representations in object agnosia is unknown. We studied a patient with object agnosia following isolated damage to the left occipito-temporal cortex overlapping with the LOC. The patient showed intact processing of object structure, yet often made identification errors that were mainly based on the global visual similarity between objects. Using functional Magnetic Resonance Imaging (fMRI) we found that the damaged as well as the contralateral, structurally intact right LOC failed to show any object-selective fMRI activity, though the latter retained selectivity for faces. Thus, unilateral damage to the left LOC led to a bilateral breakdown of neural responses to a specific stimulus class (objects and artefacts) while preserving the response to a different stimulus class (faces). These findings indicate that representations of structure necessary for the identification of objects crucially rely on bilateral, distributed coding of shape features.

UNIGE affiliation entities

UNIGE research groups

Citation (ISO format)

PTAK, Radek et al. Visual object agnosia is associated with a breakdown of object-selective responses in the lateral occipital cortex. In: Neuropsychologia, 2014, vol. 60, p. 10–20. doi: 10.1016/j.neuropsychologia.2014.05.009

Article (Published version)

Identifiers

PID : unige:39476
DOI : 10.1016/j.neuropsychologia.2014.05.009
PMID : 24863251

Journal ISSN

0028-3932

782views

1484downloads

Creation

06/08/2014 16:46:00

First validation

06/08/2014 16:46:00

Update

14/03/2023 21:31:23

Status update

14/03/2023 21:31:23

Last indexation

30/10/2024 19:43:31

Visual object agnosia is associated with a breakdown of object-selective responses in the lateral occipital cortex

Contributors

Published in

Publication date

Abstract

UNIGE affiliation entities

UNIGE research groups

Citation (ISO format)

Main files (1)

Identifiers

Journal ISSN

Technical informations

Creation

First validation

Update

Status update

Last indexation