Sensitivity Enhancement of Speech Perception in Noise by Sound Training: Hearing Loss Simulation Study

Abstract

Purpose Speech perception in noise is one of most important factors which people with hearing loss desire for better hearing. This study aims to verify the effectiveness of sound training for speech perception enhancement in background noise. Methods In our experiments, persons with normal hearing listened sounds coming through a hearing loss simulator to make them experience hearing loss virtually. In the sound training, we used the spectral ripple noise that is highly correlated to the sensitivity of speech perception in quit and noise with normal hearing person, hearing impaired person,hearing aid user, and cochlear implant user. Fourteen normalhearing subjects participated in this study. To investigate the effect of the sound training, we divided the subjects into 2group “Training group”, “Non Training group”. Each group consists of 7 normal hearing persons (Training group: male-6, female-1, Non Training group: male-5, female-2). Results The effectiveness of sound training was evaluated by the threshold of spectral resolution discrimination and the threshold of Speech perception. It was also statistically analyzed by Wilcoxon Signed test (*p<0.05). In training group, spectral resolution has improved from 8.6 ripple per octave (RPO) to 13.6 RPO. Speech perception in white noise has improved from -4.6 dB to -7.7 dB. In addition, speech perception in babble noise has improved from -4.3 dB to -7.4dB. The results were statistically significant in the training group. On the other hand, non-training group improved spectral resolution from 8 RPO to 8.4 RPO, but this result did not show statistical significance. Also speech perception in both babble and white noise did not show statistical significance. Conclusions Our results suggest that the perceptual improvement of spectral-component dissolving is significantly reflects to the speech perception in noise.