Does Congenital Deafness Affect the Structural and Functional Architecture of Primary Visual Cortex?
C.R. Smittenaar1, *, M. MacSweeney2, 3, M.I. Sereno1, 4, D.S. Schwarzkopf1, 2
Identifiers and Pagination:Year: 2016
First Page: 1
Last Page: 19
Publisher Id: TONIJ-10-1
Article History:Received Date: 9/5/2015
Revision Received Date: 4/10/2015
Acceptance Date: 10/10/2015
Electronic publication date: 29/2/2016
Collection year: 2016
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution-Non-Commercial 4.0 International Public License (CC BY-NC 4.0) (https://creativecommons.org/licenses/by-nc/4.0/legalcode), which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Deafness results in greater reliance on the remaining senses. It is unknown whether the cortical architecture of the intact senses is optimized to compensate for lost input. Here we performed widefield population receptive field (pRF) mapping of primary visual cortex (V1) with functional magnetic resonance imaging (fMRI) in hearing and congenitally deaf participants, all of whom had learnt sign language after the age of 10 years. We found larger pRFs encoding the peripheral visual field of deaf compared to hearing participants. This was likely driven by larger facilitatory center zones of the pRF profile concentrated in the near and far periphery in the deaf group. pRF density was comparable between groups, indicating pRFs overlapped more in the deaf group. This could suggest that a coarse coding strategy underlies enhanced peripheral visual skills in deaf people. Cortical thickness was also decreased in V1 in the deaf group. These findings suggest deafness causes structural and functional plasticity at the earliest stages of visual cortex.