Assessment of low-frequency hearing with narrow-band chirp-evoked 40-Hz sinusoidal auditory steady-state response

Abstract

Objective To determine the clinical utility of narrow-band chirp-evoked 40-Hz sinusoidal auditory steady state responses (s-ASSR) in the assessment of low-frequency hearing in noisy participants. Design Tone bursts and narrow-band chirps were used to respectively evoke auditory brainstem responses (tb-ABR) and 40-Hz s-ASSR thresholds with the Kalman-weighted filtering technique and were compared to behavioral thresholds at 500, 2000, and 4000 Hz. A repeated measure ANOVA and post-hoc t-tests, and simple regression analyses were performed for each of the three stimulus frequencies. Study sample Thirty young adults aged 18–25 with normal hearing participated in this study. Results When 4000 equivalent response averages were used, the range of mean s-ASSR thresholds from 500, 2000, and 4000 Hz were 17–22 dB lower (better) than when 2000 averages were used. The range of mean tb-ABR thresholds were lower by 11–15 dB for 2000 and 4000 Hz when twice as many equivalent response averages were used, while mean tb-ABR thresholds for 500 Hz were indistinguishable regardless of additional response averaging. Conclusion Narrow-band chirp-evoked 40-Hz s-ASSR requires a ∼15 dB smaller correction factor than tb-ABR for estimating low-frequency auditory threshold in noisy participants when adequate response averaging is used.

Key Words:

• Auditory steady-state response
• auditory brainstem response
• Kalman-weighted filtering

Acknowledgements

Support was provided by the Graduate College of Missouri State University and grant R03 DC012844 (J.T.L.) from the National Institutes of Health, National Institute on Deafness and Other Communication Disorders. We thank Vivosonic Inc. for providing equipment used for data collection, Dr. Aaron Steinman for technical consultation during this study, Professor John D. Durrant for input on stimulus calibration, and Professor John J. Guinan Jr., Ms. Alyssa Everett, and Ms. Kaitlyn Kennedy for productive criticisms on earlier versions this report. We also thank three anonymous reviewers for providing suggestions for improving this manuscript. Portions of this work were presented at the 2013 AudiologyNow! Annual Convention of the American Academy of Audiology in Anaheim, USA, on April 25, 2013 and the 37^th Annual MidWinter Meeting of the Association for Research in Otolaryngology in San Diego, USA, on February 24, 2014.

Declaration of interest

The authors report no conflicts of interest.