FMRI studies of effects of hearing status on audio-visual speech perception

The overall goal of this research is to acquire a more complete picture of the neurological processes of visual influences on speech perception and to investigate effects of hearing status on AV speech perception. More specifically, functional magnetic resonance imaging (fMRI) was used to investigate the brain activity underlying audio-visual speech perception in three groups of subjects: (1) normally hearing, (2) congenitally deafened signers (American Sign Language) who do not use hearing aids, and (3) congenitally hearing impaired individuals with hearing aids. FMRI data were collected while subjects experienced three different types of speech stimuli: video of a speaking face with audio input, audio speech without visual input, and video of a speaking face without audio input. The cortical areas found to be active for speechreading included: visual cortex, auditory cortex (but not primary auditory cortex), speech motor network areas, supramarginal gyrus, thalamus, superior parietal cortex and fusiform gyrus. For hearing impaired subjects, in addition to the areas listed above, Heschl's gyrus, right angular gyrus (AG), cerebellum and regions around right inferior frontal sulcus (IFS) in the frontal lobe were also found to be active.

Department dc:contributor.department

Harvard University--MIT Division of Health Sciences and Technology.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Yoo, Julie J

Advisor dc:contributor.advisor

• Frank H. Guenther.

• Harvard University--MIT Division of Health Sciences and Technology.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/38591
• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Identifier URI

http://dspace.mit.edu/handle/1721.1/38591

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/38591