Auditory steady-state responses. Literature review

Abstract

Auditory steady state response (ASSR-test) is the auditory response of the brain to frequency-specific stimuli, providing the objective assessment of auditory sensitivity in the individuals with normal hearing or various degrees and configurations of hearing loss. In view of this fact it is important to understand the test principles: the registration parameters, the correlation with behavioral thresholds of auditory perception in various clinical populations. Objective: To analyze the parameters and capabilities of the ASSR-test for application in surdological and otorhinolaryngological practice; to determine, based on literature sources, the correlation of ASSR and behavioral thresholds in various clinical populations of adults and children. Design: The review consists of several sections, including ASSR history, terminology, types of stimuli, technical parameters of ASSR recording. Besides, the article considers the effect of monofrequency and polyfrequency stimulation on the accuracy of behavioral threshold assessment, the difference between monaural and binaural stimulation, the effect of hearing loss degree and audiogram configuration on ASSR thresholds, reliability of repeated testing, the effect of degree of nerve fiber maturation on ASSR thresholds, the dependence of the result on various technical factors. Conclusion: In the present-day audiology, ASSR-test plays an important role; therefore, it is important that the specialists have an idea about ASSR capabilities and technical properties: the optimal stimulation and registration methods, the possibilities and/or limitations of ASSR application for assessment of behavioral thresholds in the patients with various degree of hearing loss and program configuration.