Evolution of crossmodal reorganization of the voice area in cochlear-implanted deaf patients.
Details
Serval ID
serval:BIB_B91D50E32BF2
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Evolution of crossmodal reorganization of the voice area in cochlear-implanted deaf patients.
Journal
Human Brain Mapping
ISSN
1097-0193 (Electronic)
ISSN-L
1065-9471
Publication state
Published
Issued date
2012
Volume
33
Number
8
Pages
1929-1940
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov'tPublication Status: ppublish. PDF type: Research Article
Abstract
Psychophysical and neuroimaging studies in both animal and human subjects have clearly demonstrated that cortical plasticity following sensory deprivation leads to a brain functional reorganization that favors the spared modalities. In postlingually deaf patients, the use of a cochlear implant (CI) allows a recovery of the auditory function, which will probably counteract the cortical crossmodal reorganization induced by hearing loss. To study the dynamics of such reversed crossmodal plasticity, we designed a longitudinal neuroimaging study involving the follow-up of 10 postlingually deaf adult CI users engaged in a visual speechreading task. While speechreading activates Broca's area in normally hearing subjects (NHS), the activity level elicited in this region in CI patients is abnormally low and increases progressively with post-implantation time. Furthermore, speechreading in CI patients induces abnormal crossmodal activations in right anterior regions of the superior temporal cortex normally devoted to processing human voice stimuli (temporal voice-sensitive areas-TVA). These abnormal activity levels diminish with post-implantation time and tend towards the levels observed in NHS. First, our study revealed that the neuroplasticity after cochlear implantation involves not only auditory but also visual and audiovisual speech processing networks. Second, our results suggest that during deafness, the functional links between cortical regions specialized in face and voice processing are reallocated to support speech-related visual processing through cross-modal reorganization. Such reorganization allows a more efficient audiovisual integration of speech after cochlear implantation. These compensatory sensory strategies are later completed by the progressive restoration of the visuo-audio-motor speech processing loop, including Broca's area.
Keywords
Adult, Aged, 80 and over, Brain/physiology, Brain Mapping, Cochlear Implants, Deafness/physiopathology, Deafness/surgery, Female, Humans, Lipreading, Male, Middle Aged, Neuronal Plasticity/physiology, Photic Stimulation, Positron-Emission Tomography, Speech Perception/physiology, Visual Perception/physiology
Pubmed
Web of science
Create date
24/03/2013 11:01
Last modification date
20/08/2019 15:27