Estimating hearing thresholds in rodents using the parallel auditory brainstem response

ABR thresholds are traditionally measured for one sound frequency at a time, but a new approach, the parallel ABR (pABR), has recently been developed. The pABR allows thresholds to be measured for multiple frequencies simultaneously and has been shown to be more efficient than the traditional approach for humans. This study explored the applicability of the pABR approach for threshold measurement in gerbils. The basic properties of the estimated ABRs were analyzed and the dependence of the signal-to-noise ratio (SNR) and the reliability of measured thresholds on the number of trials was assessed. For a subset of ears, direct comparisons were made between the pABR and the traditional approach. The results suggest that the pABR approach can be more efficient for rodents than the traditional ABR approach, particularly for threshold estimation. To facilitate its use, software toolboxes in Matlab and Python are provided for the design of the pABR sounds and the analysis of recordings.