Amplitude And Latency Studies Of The Averaged Auditory Evoked Responses To Tones Of Different Intensities

Abstract

“Saturation” and decline in peak amplitude of human scalp-derived averaged auditory evoked responses (AER) were regularly observed at high intensity levels of sound stimulation. The poztsynaptic origin of these phenomena is emphasized. It was found that “saturation” and decline arise at relatively low sensation levels in persons with unilateral deafness (i.e. when “cross hearing” is excluded) as compared with persons having normal hearing. This suggests that the AER generating mechanism contains two relatively independent symmetrical systems which are unequally influenced by the ipsilateral and contralateral cochleae. Data are also presented (e.g. “saturation” of the AER amplitude at lower stimulation levels, different thresholds and individual changes of the early and late components of AER) which are indicative of the complex mechanism of the formation of the human AER.