Intensive and temporal effects in pure-tone forward masking

Intensive and temporal characteristics of forward masking were assessed using a pure-tone masker and a 1-kHz probe. For a given interval between masker and probe, the slope of the masking function tends to decrease with increasing masker frequency, but is always less than unity. When the masker frequency equals that of the probe, increasing the masker-probe interval decreases the slope of the masking function. Implications of these data for forward-masked psychophysical tuning curves are discussed. A model, based on a linear combination of exponential decays and an initial logarithmic transform of stimulus intensity, predicts the general form of the masking function for varying interval between masker and probe, and suggests time constants which decrease with increasing masker level.