Auditory evoked potentials are bioelectrical responses to stimulation of the auditory nervous system and the corresponding central nervous system, and are used to verify that hearing abnormalities are not due to neurogenic causes. It is also a sensitive indicator of brainstem damage, because any lesion or damage anywhere in the pathway from the auditory to the central nervous system will affect this indicator. If the brainstem is slightly damaged and there are no clinical signs or symptoms, then the auditory evoked potentials of the brainstem are already altered, and it is possible to detect this kind of lesion of the brainstem in a timely manner.