Long-term auditory processing outcomes in early implanted young adults with cochlear implants: The mismatch negativity vs. P300 response

Objective: Long-term outcomes of early implanted, young adult cochlear implant (CI) users remain variable. We measured auditory discrimination by means of event-related potentials in this population to examine whether variability at the level of cortical auditory processing helps to explain speech abilities. Methods: Using an auditory oddball paradigm, the P300 and Mismatch Negativity (MMN) were measured in 8 young adult CI users and 14 normal-hearing peers. We related P300 amplitude and latency to clinical speech perception scores in quiet and to duration of deafness. Results: All individuals showed P300 responses. The MMN response was less robust in both groups. There was no evidence for differences in P300 responses between CI users and controls. P300 amplitude was associated with speech perception scores (r = 0.70, p = .05) and duration of deafness (r =-0.83, p = .009). Conclusions: Early CI implantation yields good auditory processing outcomes at young adult age and, in contrast to MMN, the P300 provides a robust measure for auditory processing on an individual level. Significance: At the cortical level, early implanted, long-term CI users have good auditory discrimination, leaving variability in implantation outcomes unexplained. This group provides unique insight into the long-term neurophysiological underpinnings of early implantation. (C) 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Automated summary

The study investigated the auditory discrimination in early implanted, young adult cochlear implant users using event-related potentials, finding that P300 amplitude correlated with speech perception scores and duration of deafness. The P300 provided a robust measure for auditory processing on an individual level, suggesting good auditory outcomes in this population.