Effect of companding on speech recognition inquiet and noise for listeners with ANSD

Abstract

Objective: The present study assesses the effect of companding on speech perception in quiet and noise for listeners with auditory neuropathy spectrum disorder (ANSD). Design:Speech perception was assessed using speech reception threshold in noise (SRTn) for sentences and consonant identifi cation in quiet and at different signal-to-noise ratios (15, 10, 5, and 0 dB SNR). Study sample: Ten ANSD listeners and normal-hearing listeners participated in the study. Results: ANSD listeners required signifi cantly higher SRTn when compared to the normal-hearing listeners. Companding reduced SRTn more signifi cantly in listeners with ANSD, but for normal-hearing listeners there was only a marginal reduction. In the consonant identifi cation task, ANSD listeners performed poorer than normal-hearing listeners in quiet and noise. Companding improved consonant identifi cation in quiet and at 15 dB SNR for listeners with ANSD, whereas no improvement was observed in normal-hearing listeners. Conclusion: Results of the present study demonstrate that companding improved speech perception in quiet and noise for ANSD listeners. The amount of improvement is higher at higher SNRs. In normal-hearing listeners, companding showed marginal improve-ment in both quiet and noise. The fi ndings are discussed for rehabilitation of ANSD listeners by hearing aids which incorporate the companding strategy.