Evaluting the effect of long-term monaural hearing aid usage via auditory brainstem response

Studies have shown that long-term use of monaural hearing aid in symmetrical hearing losses may lead to physiological changes. In this research، the possibility of plasticity occurrence in bilaterally hearing impaired listeners fitted with only one hearing aid was investigated. Our study was carried out on 12 elderly listeners with a mean age of 61. 92 years who had symmetrical moderate to severe sensory neural hearing loss in both ears. All of the participants had minimum monaural hearing aid experience of 2 years. We used auditory brainstem response (ABR) testing in order to compare absolute latency and amplitude of wave V between the two ears of cases. Air conduction click stimuli were presented monaurally at 80، 90 and 100 dB nHL. Despite the shorter absolute latency of wave V in the fitted ear، no significant difference was found between the two ears (p>0. 389). The difference between wave V amplitude of both ears was greater in 90 dB nHL level (p=0. 043). Women showed shorter mean latency than men and the mean amplitude of women was greater than men. Significant gender difference was observed in absolute latency of wave V (p<0. 037). Our findings indicate that the use of monaural hearing aid in symmetrical hearing losses can induce neural plasticity within auditory brainstem pathways which can be displayed by auditory brainstem response test.