The Effect of Hearing Loss and Hearing Aid Amplification on Predicted Pitch Salience

Abstract

While hearing aids are optimized for listening to and hearing speech in noisy environ- ments, there are still many challenges when using hearing aids to listen to music. This could mean that hearing impaired individuals do not perceive music the same way a normal hearing person would. When two musical tones are played simultaneously at equal presentation levels, the tone with the higher frequency will be perceived as more salient for a normal hearing person. This phenomenon is referred to as the high voice superiority effect. This study examined how different types of hearing loss affect the neural pitch salience profile obtained with a computational model of the auditory periphery. More specifically, the high voice superiority effect was examined by generating neural pitch salience profiles for different combinations of simultaneous tones at different sound presentation levels. To model other aspects of hearing aid processing, an Analog to Digital Converter (ADC) and simple noise reduction filter were added to some of the simulations. The results show that less severe hearing loss types tend to have pitch salience profiles closer to normal after hearing aid amplification. The addition of the ADC to the simulation seems to have little effect on the pitch salience, whereas the noise reduction filter has a noticeable effect on how closely the pitch salience profile matches that of a normal hearing ear. For each different type of hearing loss there appears to be a trade-off between the ability of the upper tone and the lower tone to match normal hearing performance. Along with simulated piano tone results, pitch salience results are shown for live recordings of several instruments through hearing aids. The recordings are compared to ideal versions of the instrument parts. This study provides a starting point to improve hearing aid processing for music perception.