An auditory perception of changes in the intensity of pulses, presented in complicated sound complex

Abstract

The auditory system of humans and animals is able to detect and discriminate high frequency pulses in a sound complicated complex. The purpose of the work was to find new examples of facilitation the discrimination of intensity (or level, defined by a peak amplitude) of pulses, presented under composite masking conditions, and to find the possible mechanisms underlying the facilitation. The discrimination tended to deteriorate if the test pulse was presented via 50 ms after a pulse masker. However, if the pulse was mixed with additional noise masker, the beginning of which coincided with the end of the pulse masker, discrimination became better. The noise masker levels, at which facilitation occurred, depended on amplitudes of both the pulses and the pulse maskers. When the duration of the noise masker was less than 50 ms, an auditory adaptation could not influence on the discrimination. The reason of the facilitation could be in the temporal redistribution of the auditory nerve fibers activities, which occurred at coding of the temporal envelope of the sound complex "pulse masker - pulse - additional noise masker". © 2013 Acoustical Society of America.