The Impact of Age and Duration of Cochlear Implant in a Congenital Deaf Population: An ERP Study

Objective: It is well known that patients with Cochlear Implant (CI) have a large inter-individual variability in linguistic and auditory performances. This can be related to individual auditory processing abilities and integrity of auditory system from auditory nerve to cerebral cortex. P300 can be used for the evaluation of central auditory functions in people with hearing loss and CI. No studies considered the P300 in the population of prelingually deafened adults that underwent CI in old age. The aim of this study is to assess Event Related Potential (ERP) in patients with congenital profound hearing loss with early or late implantation and evaluate these results respect to an age-matched normal hearing group. Methods: ERPs (N100, N200 and P300) and auditory benefit testing (pure tone average and speech audiometric test) and auditory perception testing (Categories of Auditory Performance—CAP) were evaluated in all subjects with their device. Results: All mean latencies (N100, N200 and P300) were found greater in patients group compared to control group. When analyzing all measures in patient group, we did not find any significant differences according to age of implant while significant difference (p > 0.05) in N100 amplitude (p = 0.045) and P300 latency (p = 0.035) were found according to time of CI use. A linear correlation between N200 and P300 latency in control and patients groups was found. Conclusion: In summary, ERPs analysis in the evaluation of CI showed a great importance of long use of the device in addiction to an early time of implant.