Date of Award
Doctor of Audiology (AuD)
School of Communication
Melinda F. Bryan
The present study sought to determine if ANLs differ between ears within subjects with unilateral or asymmetrical SNHL. ANL was measured in four conditions (i.e., binaural, better ear, poorer ear unmasked, and poorer ear masked) in fifteen adults, nine with unilateral SNHL and six with bilateral asymmetrical SNHL. A significant difference between ANL in the four conditions (i.e., binaural, better ear, poorer ear unmasked, and poorer ear masked) was identified; however, the subjects with unilateral and asymmetrical SNHL behaved similarly throughout the testing. When comparing the four conditions, the results showed a significant difference between both the binaural ANL and better ear ANL conditions and the poorer ear unmasked ANL condition. There was no significant difference between the binaural and better ear ANL conditions or the poorer ear unmasked and the poorer ear masked conditions. Furthermore, both the binaural ANL and better ear ANL conditions versus the poorer ear masked ANL condition approached significance. Collectively these results showed that when the better of the two ears was being used, subjects had lower ANLs compared to when the poorer ear was being used. This suggested that the peripheral auditory system could be at least in part contributing to the mediated point of ANL. Alternately, ANL may be due to auditory deprivation, thus a central auditory phenomenon is the result of ANL mediation. Clinical implications/applications will be discussed.
Howard, Rebecca, "" (2015). Dissertation. 207.