Applications of the auditory brainstem response to pediatric hearing and selection

To meet the challenge of fitting amplification on young and difficult-to-test patients, some investigators have proposed that the ABR may be useful for hearing aid assessment. This article provides a review of previous work in this application. Issues related to assessing gain, frequency response, and output limitation are discussed. Results from our work suggest that the use of the ABR for hearing-aid selection is limited to estimates of high-frequency gain. Furthermore, ABR measurements are based on an onset response and may not accurately reflect hearing aid responses for the long-duration stimuli that are typically used to describe output limitation of hearing aids. A more effective approach might be one that uses the ABR to measure an evoked-potential equivalent of the pure-tone audiogram. Probe-microphone measurements then could be used to estimate hearing aid responses on individual difficult-to-test patients.