Spectral characteristics of short latency auditory evoked potentials

Abstract

Evoked potentials (EP) containing 15 components were recorded from the scalp surface in response to auditory stimulation. Short latency auditory evoked potentials (SLEP) represented seven early components occuring during 10-12 ms after the stimulation. Numerous electrophysiological studies of SLEP [2-1 !] have been carried out since the 1970s when Jevett [1] first described this type of evoked responses. However, many questions concerning the generation and propagation of particular SLEP components remained unanswered up until now. One of them concerns the frequency characteristics of SLEP. A study of this problem is quite important since spectral analysis of SLEP may yield knowledge about the new and more subtle parameters of this EP-type behavior under the change in experimental variables such as the polarity and intensity of the stimulus, the rate of its repetition, location of leads, and so on. Moreover, such studies might create prerequisites for extending the notions about EP generation mechanisms. It should be noted that just this aspect was practically neglected in the literature if not to speak about the two studies [12, 13], which did not fully use adequate spectral analysis technique with limited spectral power resolution and low accuracy of measuring the parameters of SLEP such as the range and peak values of the main frequency components.