Abstract:
The cochlear implantation has significantly improved the quality of life for children with severe to profound hearing loss. However, the speech perception outcomes remain highly variable among pediatric CI population. Hence understanding the brainstem level processing of speech may help clarify these differences. The current study aimed to compare the neural encoding of speech at the brainstem level specifically, the latency and amplitude of Wave V and the amplitudes of F0 and H2 between pediatric cochlear implant users with good and poor speech perception outcomes. Twenty children with cochlear implants (CI422 implant and CP802 processor), each with at least one year of device experience, were divided into good and poor outcomes groups based on speech identification scores. The speech evoked auditory brainstem responses(S-ABR) were recorded in a sound treated room and individual template artifact rejection technique was used for the removal of artifacts. The data analysis included comparisons of Wave V latency and amplitude, and F0 and H2 amplitudes, using independent samples t tests. There was no statistically significant differences between good and poor outcome groups for Wave V latency or amplitude, or for F0 and H2 amplitudes. However, higher mean F0 and H2 amplitudes were observed in the good outcome group. The replicability of Wave V was higher for both the groups. While subtle trends were observed, speech evoked brainstem responses alone may not fully distinguish speech perception outcomes in pediatric cochlear implant users. Hence, more research with improved techniques are needed.
