Artikel
Lateralisation of speech processing in cochlear implant users
Suche in Medline nach
Autoren
Veröffentlicht: | 31. Mai 2005 |
---|
Gliederung
Text
This study aimed to investigate hemispheric speech processing in cochlear implant users. Cortical activity resulting from auditory stimulation was measured using [18F]-FDG positron emission tomography. Eighteen adult cochlear implant users were studied over the course of 29 activation states. Four main effects were observed: (i) bilateral auditory cortical activation was present in all subjects; (ii) activity was greater in the left than the right primary areas; (iii) activity was greater in the association areas contralateral to the side of implantation; and (iv) visual cortical responses were higher in patients with left than right cochlear implants. These data demonstrate that there is no strong left hemisphere dominance for language in cochlear implant users, and suggest that lateralisation of association area speech processing shifts following cochlear implantation. The additional visual recruitment in the left implant users may be as a result of excessive demands on the speech processing abilities of the right auditory areas. In total, these findings provide evidence of the development of new speech processing strategies that occur following cochlear implantation.