An open-source system for recording the auditory brainstem response (ABR) and an example application in mice with hearing loss

The auditory brainstem response (ABR) is a measure of the neurophysiological response to sound, widely used in clinical and research settings. In this manuscript, we describe an open-source and low-cost system suitable for measuring the ABR in mice. (This system is not evaluated or approved for clinical use in humans.) The heart of the system is the commercially available Texas Instruments ADS1299 chip, which is designed for multi-channel differential recording of biosignals. We designed auxiliary hardware and software to record and visualize the ABR. To demonstrate that this system is capable of high-quality and low-noise measurements, we recorded the response to free-field auditory clicks from the left and right. Next, we compared different electrode configurations, quantified the most consistent aspects of the ABR, and assessed variability within and across mice. Finally, we demonstrated how to detect the decreased auditory sensitivity caused by surgically induced conductive hearing loss. Users can deploy this open-source system at low cost and customize it for different applications, such as recording other biosignals like electromyography (EMG) or electrocardiography (ECG).