Establishment of ANSI/ASA S3/SC1.6—Standardization of evoked potential hearing test methods in toothed whales

Abstract

The use of auditory evoked potentials (AEPs) to test the hearing of toothed whales has produced hundreds of toothed whale audiograms over the last two decades. Unfortunately, multiple approaches to obtaining AEP audiograms have been employed, including different methods for estimating the hearing threshold, the use of different acoustic test stimuli, different approaches to calibration, etc. Lack of methodological consistency has resulted in considerable variability in threshold estimates between researchers and laboratories and conclusions about differences in the hearing abilities of toothed whale populations that are likely erroneous. To address this issue, ANSI/ASA S3/SC1.6-2018 was developed. The document proposes standardized methods for performing AEP hearing tests in toothed whales. Implementation of the standard should reduce variability in threshold estimates obtained by different laboratories and researchers and make the resulting audiograms more comparable. Although AEP hearing tests are common for the clinical assessment of hearing in stranded whales and their use for this purpose is not substantially impacted by methodological variances, audiogram comparability is necessary for the broader implementation of AEP audiograms into environmental impact assessments and regulation. Thus, the standard should facilitate environmental stewardship efforts to manage the impact of anthropogenic sound on marine mammals.The use of auditory evoked potentials (AEPs) to test the hearing of toothed whales has produced hundreds of toothed whale audiograms over the last two decades. Unfortunately, multiple approaches to obtaining AEP audiograms have been employed, including different methods for estimating the hearing threshold, the use of different acoustic test stimuli, different approaches to calibration, etc. Lack of methodological consistency has resulted in considerable variability in threshold estimates between researchers and laboratories and conclusions about differences in the hearing abilities of toothed whale populations that are likely erroneous. To address this issue, ANSI/ASA S3/SC1.6-2018 was developed. The document proposes standardized methods for performing AEP hearing tests in toothed whales. Implementation of the standard should reduce variability in threshold estimates obtained by different laboratories and researchers and make the resulting audiograms more comparable. Although AEP hearing tests are commo...