Auditory event-related potentials in post- and prelingually deaf cochlear implant recipients.
The development of central auditory functions in cochlear implant (CI) patients was studied over six months of rehabilitation. Examinations were performed beginning with the first week after processor calibration, and in monthly follow-up sessions thereafter. The subjects were given a simple auditory perception task (detection of a 400 Hz and a 1450 Hz tone), as well as an oddball-paradigm (detection of one of the tones as a rare deviant). Auditory evoked potentials, reaction time and errors were recorded. Results from five patients, two postlingually deaf and three prelingually deaf CI recipients are shown. Generally, in the auditory evoked potentials of patients a shortening of N100 latency towards those of subjects with normal hearing was seen from month to month. However, in the prelingually deaf patients this effect was weaker and more variable over time. Three CI recipients showed a P300 component in the oddball-paradigm in correlation with their performance. Two prelingually deaf patients failed to show a P300 in the oddball-paradigm. For both components, the N100 and the P300 we found a larger spreading over the skull in the patients compared to a normal hearing person. The results show that from the very first days after initial processor fitting prelingually and postlingually deaf CI recipients may show cortical correlates of stimulus processing and discrimination. For some components of the auditory evoked potentials an initial temporal change but a maintained larger spreading over the skull was seen.
Jordan
K
K
Federal Institute for Neurobiology, Magdeburg, Germany.
Schmidt
A
A
Plotz
K
K
von Specht
H
H
Begall
K
K
Roth
N
N
Scheich
H
H
D019929:Cochlear Implantation; D003638:Deafness / Q000503:physiopathology* / Q000534:rehabilitation*; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory; D006309:Hearing / Q000502:physiology; D006801:Humans; D013067:Speech Perception