Guest, Hannah and Plack, Christopher J. and Munro, Kevin J. and Couth, Samuel and Prendergast, Garreth (2025) Independent effects of sex and ear-canal size on auditory brainstem response amplitudes in young adults. International Journal of Audiology. pp. 1-8. ISSN 1499-2027
Full text not available from this repository.Abstract
Objective Adult auditory brainstem response (ABR) amplitudes are employed by both researchers and clinicians, but exhibit substantial between-subject variability, reducing their sensitivity as measures of underlying auditory health. One source of variability is sex, for which a number of mechanisms have been proposed. The present analysis aimed to determine whether ear-canal size influences ABR wave I amplitude, independent of sex. Design ABR wave I amplitudes and estimates of ear-canal diameter and volume were obtained from 220 otologically healthy teenagers. Multiple linear regression models tested for independent effects of sex and ear-canal size on ABR amplitudes. Study sample Participants were enrolled in a longitudinal study conducted by the Manchester Centre of Audiology and Deafness. The present data were gathered at baseline (age 16–17 years). Results The size of the sex effect on wave I amplitude was reduced by adding ear-canal diameter or volume to the model, but it remained significant. Ear canal diameter contributed modestly to wave I amplitude, independent of sex. Ear-canal volume produced null results. Conclusions Findings are preliminary and strictly exploratory, but suggest that women’s larger ABR amplitudes may be explained in part by their smaller ear canals, with implications for the sensitivity, comfort, and safety of ABR testing.