Temporal processing and speech recognition in cochlear implant users

TLDR

Speech recognition performance in cochlear implant patients has improved, yet substantial outcome variability persists. This study examines the relationship between auditory temporal processing and speech recognition in cochlear implant users. Modulation detection thresholds were measured across stimulation levels, and phoneme recognition was evaluated. Individual differences in modulation threshold shape and sensitivity correlated strongly with phoneme recognition scores, indicating temporal processing contributes to speech perception and informing future processor design and rehabilitation.

Abstract

Although the speech recognition performance of cochlear implant patients has steadily improved in recent years, considerable variability remains in implant patient outcomes. Here, we report on a correlation between cochlear implant patients' auditory temporal processing and speech recognition abilities. Modulation detection thresholds were measured as a function of stimulation level; phoneme recognition was also assessed. Results showed marked individual differences in the shape and absolute sensitivity of subjects' modulation threshold functions. Statistical analysis revealed a strong correlation between phoneme recognition scores and subjects' mean modulation thresholds, demonstrating the contribution of temporal processing to implant speech perception. In correlating a basic psychophysical measure to speech performance, these results should contribute toward improved speech processor design and rehabilitation tools for cochlear implant patients.