Relationship between Effective Duration and Intelligibility of Japanese Monosyllables in Individuals with Sensorineural Hearing Loss

Among the temporal elements in the autocorrelation function, the effective duration (t(e)) is a useful indicator of speech recognition for patients with sensorineural hearing impairment. We assessed the influence of speech recognition performance on the relationship between the percentage of accurately perceived articulation and the median t(e) (t(e)-med) and the relationship between monosyllabic confusion and the t(e)-med. Significant correlations were observed between the articulation percentage and the average t(e)-med in groups with high, middle, and low speech recognition scores (SRSs). Two-factor mixed analysis of variance revealed significant main effects for the condition (presentation/response). There was no significant main effect for group (high-, middle-, or low-SRS) scores and no significant interaction between the groups. The average t(e)-med of the response was significantly longer than that of the presentation in all three groups. Monosyllables with short t(e)-med values tended to be misheard as monosyllables with a long t(e)-med when confusion occurred. The t(e)-med was useful for estimating monosyllables that patients with sensorineural hearing impairment find easy to listen to, independent of speech recognition performance.