[Age and features of cortical auditory evoked potentials]

Abstract

Auditory evoked potentials (AEP) elicited by acoustic stimuli of various frequencies and intensities were studied in children aged from three to sixteen years. With age, peak latencies of the AEP components decrease on the average (taking into account the differences of such changes depending on the frequency and intensity of the stimuli presented) by 67.6 +/- +/- 13; 82.0 +/- 7.5; 65.6 +/- 7.2; 32.3 +/- 6.7 ms for components P1, N1, P2, N2 respectively. In 90% of the cases the thresholds of auditory sensations coincided with AEP thresholds; in 10% of the cases the thresholds of electrocortical reactions were by 5 dB lower than those of the auditory sensations. Enhancement of the stimulus to 80 dB lead to an increase of the AEP amplitude, while further augmentation of stimulus intensity in most cases resulted in a decrease of the AEP amplitude which was accompanied by unpleasant sensations or preceded their appearance. The frequency of this phenomenon drops with the age from 90% in 3-4 years old children, down to 30% in juveniles 15-16 years old.