Effect of Hearing Aid Usage on Auditory Perceptual Learning in Individuals with Hearing Loss

Abstract

Introduction: Auditory perceptual learning, driven by training, can enhance performance on sensory tasks and induce lasting changes in perceptual systems. Individuals with hearing loss often encounter difficulties in perceptual learning due to lack of sufficient stimulation. Understanding how the auditory system adapts in these situations is essential for enhancing auditory processing through interventions such as hearing aids. Cognitive factors such as working memory can significantly influence auditory perceptual learning. Aim: The aim of the study was to investigate the effect of hearing aid use on auditory perceptual learning among individuals with hearing loss Method: Twenty individuals in the age range of 20 to 50 years (mean age 40.45 ± 13.17 years) were the participants of the study. They were divided into two groups: Group I included 10 individuals who used bilateral hearing aids (HA), and Group II comprised of 10 individuals who did not use hearing aids despite having hearing loss. Both the groups had participants with mild and moderate severity of hearing loss. The study comprised three phases: Phase I involved pre-training audiological and auditory working memory assessments. The audiological evaluation included speech identification scores (SIS) for time-compressed PB words at a 50% compression ratio, monosyllables at a 60% compression ratio, and speech perception in noise. Auditory working memory tests included backward digit span and operational span tests. Phase II involved auditory perceptual training, conducted over seven sessions on time-compressed speech for both PB words and monosyllables using distinct list from pre-/post-test evaluations. Importantly, no training was provided for speech perception in noise during this phase. Phase III comprised post-training evaluations, including audiological assessments. Results: The results revealed that hearing aid usage significantly influenced auditory perceptual learning outcomes in participants with moderate hearing loss, particularly on trained tasks such as SIS for time-compressed PB words and monosyllables. However, no significant differences were observed between hearing aid users and non-users with mild hearing loss among any of the tasks. Both groups showed considerable improvement in time-compressed speech and speech perception in noise following training, with p-values <0.05 indicating statistical significance. Additionally, there was no significant correlation found between changes in scores post-training and measures of auditory working memory. Conclusions: Consistent use of hearing aids facilitates adaptation to amplified sounds and improves auditory perceptual training, leading to enhanced hearing performance. Individuals with moderate hearing loss benefit significantly from hearing aids by improving audibility. For those with mild hearing loss, some auditory stimulation occurs even without hearing aids, which may explain minimal differences in training outcomes between users and non-users in this group.Moreover, the study found no significant correlation between auditory stimuli and measures of working memory. This result could be attributed to the use of time-compressed speech stimuli in the study, primarily targeting temporal resolution rather than cognitive abilities. Differences in brain regions involved in auditory versus cognitive processing likely contribute to this finding. Additionally, individual variations in working memory capacity may influence the relationship between auditory.