The Changes of Auditory Brainstem Response (ABR) in Monaural and Binaural Stimulation

Simultaneous bilateral recordings of ABR in cats were performed using binaural and monaural stimulation following the section of the eighth nerve and the auditory ascending cross pathway (cochlear nucleus-superior olivary nucleus level).The results were as follows:1) Waves 1 and 2 seem to represent the potentials of the ipsilateral cochlear nerve and cochlear nucleus.2) Waves 3, 4 and 5 seem to represent the potentials of the contralateral brainstem evoked potentials.3) Wave 3 is related to the contralateral superior olivary nucleus, wave 4 to the contralateral superior olivary ascending pathway and wave 5 to the contralateral inferior colliculus.4) In order to locate the lesions, ABR should be evaluated whether there is the response to binaural or monaural stimulation or not.