Monaural Temporal Masking Investigated by Binaural Interaction

Abstract

Three experiments were conducted to study monaural temporal masking as manifested in binaural interactions. The experimental paradigm consisted of presenting a pair of clicks in one ear and a single “probe” click in the other. The ability of listeners to bring the probe click into fusion with one or the other contralateral click served as the principal measure of masking. Forward masking (inability to fuse the second click) was studied as a function of repetition rate and click levels. The forward-masking interval increased with increase of first-click intensity and, notably, decreased with increase of repetition rate. For the conditions and procedure of this experiment, the longest forward-masking interval was about 7 msec. Backward masking (inability to fuse the first click) appeared when the monaural clicks were proximate (up to 2 msec in this experiment) and the second click was much more intense than the first. This type of backward masking was deemed a short-term effect and was distinguished from long-term backward masking. A model is presented to account for the improved resolution at high repetition rates.