Effects of noise exposure on auditory brainstem response and speech-in-noise tasks: a review of the literature

Abstract

Objective: Short-term noise exposure that induces transient changes in thresholds has induced permanent cochlear synaptopathy in multiple species. Here, the literature was reviewed to gain translational insight into the relationships between noise exposure, ABR metrics, speech-in-noise performance and TTS in humans.

Design: PubMed-based literature search, retrieval and review of full-text articles. Study Sample: Peer-reviewed literature identified using PubMed search.

Results: Permanent occupational noise-induced hearing loss (NIHL) is frequently accompanied by abnormal ABR amplitude and latency. In the absence of NIHL, there are mixed results for relationships between noise exposure and ABR metrics. Interpretation of speech-in-noise deficits is difficult as both cochlear synaptopathy and outer hair cell (OHC) loss can drive deficits. Reductions in Wave I amplitude during TTS may reflect temporary OHC pathology rather than cochlear synaptopathy. Use of diverse protocols across studies reduces the ability to compare outcomes across studies.

Conclusions: Longitudinal ABR and speech-in-noise data collected using consistent protocols are needed. Although speech-in-noise testing may not reflect cochlear synaptopathy, speech-in-noise testing should be completed as part of a comprehensive test battery to provide the objective measurement of patient difficulty.

Key Words:

• Cochlear synaptopathy
• auditory brainstem response
• evoked potential
• speech in noise testing
• signal in noise testing

Declaration of interest

Funding for previously completed studies on temporary threshold shift in humans was provided by U01 DC 008423 from the National Institutes of Health – National Institute on Deafness and Other Communication Disorders (NIH-NIDCD), as well as contracts to the University of Florida awarded by Sound Pharmaceuticals, Inc. and Edison Pharmaceuticals, Inc. Support for the preparation of this manuscript was provided by the Emilie and Phil Schepps Distinguished Professorship in Hearing Science at the University of Texas at Dallas.