Temporal masking of a click by noise in diotic and dichotic listening conditions

Forward, backward, and combined forward-backward masking of a 1-msec click by noise bursts were examined for diotic and dichotic stimulus configurations. The silent interval between the noise masker and the click ranged from 0 to 40 msec for forward and backward masking conditions. For combined forward-backward masking the silent interval between the two noise maskers ranged from 1 to 60 msec, and the click was positioned at 10-msec intervals within this gap. Masking level differences (MLD's) were obtained for all temporal conditions studied, but were largest for backward masking when the interval between the masker and click was 0 msec. For the combined forward-backward masking procedure, the effects of forward and backward maskers were roughly equivalent in the homophasic condition, but for the antiphasic condition the backward masker was considerably less effective than the forward masker. For homophasic stimuli, the magnitude of additional masking was dependent upon masker intensity. There was little or no evidence of additional masking for antiphasic stimuli.