Categorical representation from sound and sight in the ventral occipito-temporal cortex of sighted and blind
- Université catholique de Louvain, Belgium
- Université catholique de Louvain (UcL), Belgium
- University of Trento, Italy
Abstract
Is vision necessary for the development of the categorical organization of the Ventral Occipito-Temporal Cortex (VOTC)? We used fMRI to characterize VOTC responses to eight categories presented acoustically in sighted and early blind individuals, and visually in a separate sighted group. We observed that VOTC reliably encodes sound categories in sighted and blind people using a representational structure and connectivity partially similar to the one found in vision. Sound categories were, however, more reliably encoded in the blind than the sighted group, using a representational format closer to the one found in vision. Crucially, VOTC in blind represents the categorical membership of sounds rather than their acoustic features. Our results suggest that sounds trigger categorical responses in the VOTC of congenitally blind and sighted people that partially match the topography and functional profile of the visual response, despite qualitative nuances in the categorical organization of VOTC between modalities and groups.
Data availability
Processed data have been made available on OSF at the link https://osf.io/erdxz/. To preserve participant anonymity and due to restrictions on data sharing in our ethical approval, fully anonymised raw data can only be shared upon request to the corresponding author.
Article and author information
Author details
Funding
European Commission (Starting Grant MADVIS: 337573)
- Olivier Collignon
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The ethical committee of the University of Trento approved this study (protocol 2014-007) and participants gave their informed consent before participation.
Copyright
© 2020, Mattioni et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Categorical representation from sound and sight in the ventral occipito-temporal cortex of sighted and blind
eLife 9:e50732.
https://doi.org/10.7554/eLife.50732
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