Influence of Tinnitus-Control Sound Stimuli on Auditory Spectral and Temporal Resolution and Speech Perception in Hearing Aid Users

Abstract

Background and Objectives: Hearing aids (HAs) with built-in sound generators can alleviate the discomfort of tinnitus in individuals with tinnitus and impaired hearing. However, it is unknown how tinnitus-control sound (TCS) affects speech perception in HA users. Therefore, this study aimed to evaluate the effect of HA TCS on auditory spectral resolution, temporal resolution, and speech perception in individuals with tinnitus and impaired hearing. Materials and Methods: The subjects were 13 elderly listeners (62.38±8.44 years, seven males, six females) with tinnitus and impaired hearing who had been using a receiver-in-canal HA with a built-in sound generator in everyday life for more than 3 months. The following psychoacoustic measurements were performed: spectral-ripple discrimination (SRD), temporal modulation detection (TMD), and speech recognition threshold in noise. The results obtained with HA-only and HA plus TCS conditions were compared. Results: There were no significant differences in SRD and TMD between the HA-only and HA plus TCS conditions (p>0.05). However, the HA plus TCS conditions were associated with worse speech recognition than the HA-only conditions (p=0.027). Conclusions: TCS constrains speech perception in noise in individuals with tinnitus and impaired hearing, implying that the TCS introduces additional noise to existing tinnitus. Therefore, we recommend that individuals with tinnitus who use a HA with a built-in sound generator should turn off the sound generator in daily life, especially in noisy environments.