Loudness changes associated with the perception of an auditory after-image.

The Zwicker tone (ZT) is an auditory sensation that occurs following the presentation of broadband noise containing a spectral notch. The present study aimed to test whether the changes in auditory thresholds that have been shown to follow the presentation of the ZT inducer are accompanied by suprathreshold effects. Using an interaural loudness-balance procedure, the loudness of probe tones presented after notched and after flat noise was compared. The results revealed small differences in the influence of the two types of noise on loudness at low intensities only. This suggests that the influence of notched noise stimulation on the auditory system is mediated by changes in the internal noise in auditory centres.