The tone-evoked auditory brainstem responses (tone-ABR)

Abstract

Introduction: The tone-evoked auditory brainstem responses (tone-ABR) allow us to infer the hearing sensitivity and to estimate the hearing threshold at various frequencies of the audiogram. Objective: To describe the findings of the tone-evoked auditory brainstem response in the frequencies of 0.5, 1, 2 and 4 kHz in adult listeners and compare the pure-tone threshold. Results: It was obtained the minimum response level of 25, 20, 21 and 20 dBnHL at frequencies of 0.5, 1, 2 and 4 kHz respectively, and the differences between the minimum level of response and the pure-tone threshold of 15.0, 11.1, 12.2 and 13.9 dB respectively. At 70 dBnHL it was observed a latency of 9.0, 7.4, 6.6 and 6.2 milliseconds to 0.5, 1, 2 and 4 kHz, respectively. Conclusion: NMR showed high frequencies close to hearing threshold and wave V latency longer for the low frequencies. Differences of up to 15 dBnNA can be observed between the NMR and electrophysiological auditory threshold tonal.