Study of simultaneous bilateral auditory brainstem response recordings based on spread spectrum technology

Long testing durations are the major challenge in the clinical application of auditory brainstem response (ABR), and simultaneous bilateral testing is a potential solution. However, when identical stimuli are presented to both ears simultaneously, binaural interactions occur, complicating the identification of each ear's true response. Thus, this study applies the spread spectrum technology to ABR testing by employing a random stimulus rate for each ear, enabling simultaneous and independent assessment of bilateral ears (ssBi-ABR). The ssBi-ABR results were compared with traditional unilateral auditory brainstem response (uABR) results to examine the effectiveness of the ssBi-ABR method. No significant difference in the response threshold was observed between the two methods. Although ssBi-ABR showed significantly longer latencies (except wave I) and lower amplitudes than uABR, the average differences were both relatively small (<0.1 ms and <0.1 μV). The testing duration of ssBi-ABR was significantly shorter than that of uABR, on average, requiring only 63% of the time needed for uABR. The findings demonstrate that the application of spread spectrum technology enables effective and simultaneous bilateral ABR testing, which could significantly reduce the testing time without compromising the accuracy of the results.