Spectral Resolution and Speech Perception in Cochlear Implanted School-Aged Children.

Abstract

Cochlear implantation of prelingually deaf infants provides auditory input sufficient to develop spoken language; however, outcomes remain variable. Inability to participate in speech perception testing limits testing device efficacy in young listeners. In postlingually implanted adults (aCI), speech perception correlates with spectral resolution an ability that relies independently on frequency resolution (FR) and spectral modulation sensitivity (SMS). The correlation of spectral resolution to speech perception is unknown in prelingually implanted children (cCI). In this study, FR and SMS were measured using a spectral ripple discrimination (SRD) task and were correlated with vowel and consonant identification. It was hypothesized that prelingually deaf cCI would show immature SMS relative to postlingually deaf aCI and that FR would correlate with speech identification. Cross-sectional study. In-person, booth testing. SRD was used to determine the highest spectral ripple density perceived at various modulation depths. FR and SMS were derived from spectral modulation transfer functions. Vowel and consonant identification was measured; SRD performance and speech identification were analyzed for correlation. Fifteen prelingually implanted cCI and 13 postlingually implanted aCI were included. FR and SMS were similar between cCI and aCI. Better FR was associated with better speech identification for most measures. Prelingually implanted cCI demonstrated adult-like FR and SMS; additionally, FR correlated with speech identification. FR may be a measure of CI efficacy in young listeners.