A positive wave at 8 ms (P8) and modified auditory brainstem responses measurement in auditory neuropathy spectrum disorder

Abstract Objective Auditory neuropathy spectrum disorder (ANSD) is characterized by absent or atypical auditory brainstem responses (ABR), recordable otoacoustic emissions and/or cochlear microphonics. Modification of ABR stimuli is discussed to improve wave V synchronization in ANSD patients. Design Ten ANSD children (seven unilateral) underwent ABR measurement with an alternating stimulus (40.5 s −1 ), constant rarefaction and condensation stimuli, a reduced click-rate (11.1 s −1 ) and a chirp-stimulus. Results The results showed no remarkably better synchronization with modified stimuli. Whereas higher levels showed no synchronization, reproducible positive waves at 8 ms (P8) at intensities of 65–85 dB were found in six patients with all stimuli. Conclusions We suggest an ipsilateral auditory origin of the positive potentials at 8 ms. They could be characteristic of synchronization abnormalities in some cases of ANSD.