Effect of companding on speech recognition in quiet 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 identification 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 significantly higher SRTn when compared to the normal-hearing listeners. Companding reduced SRTn more significantly in listeners with ANSD, but for normal-hearing listeners there was only a marginal reduction. In the consonant identification task, ANSD listeners performed poorer than normal-hearing listeners in quiet and noise. Companding improved consonant identification 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 improvement in both quiet and noise. The findings are discussed for rehabilitation of ANSD listeners by hearing aids which incorporate the companding strategy.

Key Words::

• Behavioral measures
• assistive technology
• speech perception
• psychoacoustics/hearing science

Acknowledgements

We wish to thank our Director, All India Institute of Speech and Hearing, for allowing us to conduct the study. We extend our thanks to Frederick Gallun and Eric Chelline for timely help. Finally we thank all our participants for their patient cooperation.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.