Cortical Neurophysiologic Correlates of Auditory Threshold in Adults and Children With Normal Hearing and Auditory Neuropathy Spectrum Disorder

Abstract

Purpose Auditory threshold estimation using the auditory brainstem response or auditory steady state response is limited in some populations (e.g., individuals with auditory neuropathy spectrum disorder [ANSD] or those who have difficulty remaining still during testing and cannot tolerate general anesthetic). However, cortical auditory evoked potentials (CAEPs) can be recorded in many such patients and have been employed in threshold approximation. Thus, we studied CAEP estimates of auditory thresholds in participants with normal hearing, sensorineural hearing loss, and ANSD. Method We recorded CAEPs at varying intensity levels to speech (i.e., /ba/) and tones (i.e., 1 kHz) to estimate auditory thresholds in normal-hearing adults ( n = 10) and children ( n = 10) and case studies of children with sensorineural hearing loss and ANSD. Results Results showed a pattern of CAEP amplitude decrease and latency increase as stimulus intensities declined until waveform components disappeared near auditory threshold levels. Overall, CAEP thresholds were within 10 dB HL of behavioral thresholds for both stimuli. Conclusions The above findings suggest that CAEPs may be clinically useful in estimating auditory threshold in populations for whom such a method does not currently exist. Physiologic threshold estimation in difficult-to-test clinical populations could lead to earlier intervention and improved outcomes.