Abstract
Introduction The P3 cognitive evoked potential is recorded when a subject correctly identifies,
evaluates and processes two different auditory stimuli.
Objective to evaluate the latency and amplitude of the P3 evoked potential in 26 cochlear implant
users with post-lingual deafness with good or poor speech recognition scores as compared
with normal hearing subjects matched for age and educational level.
Methods In this prospective cohort study, auditory cortical responses were recorded from
26 post-lingual deaf adult cochlear implant users (19 with good and 7 with poor speech
recognition scores) and 26 control subjects.
Results There was a significant difference in the P3 latency between cochlear implant users
with poor speech recognition scores (G-) and their control group (CG) (p = 0.04), and between G- and cochlear implant users with good speech discrimination
(G+) (p = 0.01). We found no significant difference in the P3 latency between the CG and
G+. In this study, all G- patients had deafness due to meningitis, which suggests
that higher auditory function was impaired too.
Conclusion Post-lingual deaf adult cochlear implant users in the G- group had prolonged P3 latencies
as compared with the CG and the cochlear implant users in the G+ group. The amplitudes
were similar between patients and controls. All G- subjects were deaf due to meningitis.
These findings suggest that meningitis may have deleterious effects not only on the
peripheral auditory system but on the central auditory processing as well.
Keywords
P3 event-related potentials - cochlear implant - speech discrimination
