Temporal integration of forward masking in normal and hearing‐impaired listeners

Abstract

Listeners with cochlear pathology often demonstrate less temporal integration at threshold than normal listeners. One explanation for that finding is that the pathologic ear is prone to excessive fatigue or adaptation to brief sounds. If this is indeed the case, it might be expected that the growth of forward masking with masker level would be less influenced by masker duration for listeners with sensorineural losses than for normal‐hearing listeners. To test this hypothesis, we measured the growth of tonal forward masking as a function of masker level at several different masker durations for both normal‐hearing and cochlear‐impaired listeners. Masker duration ranged from 35 to 500 ms and probe duration was 20 ms with a 10‐ms masker‐probe time delay. In addition, unmasked probe thresholds were measured for probes ranging from 20 to 500 ms. Generally, it was found that those hearing‐impaired listeners demonstrating less‐than‐normal temporal integration at threshold, also showed little effect of varying masker duration for forward masking. This suggests that integration of energy at probe threshold and integration of masker energy for forward masking are related phenomena. [Work supported by a David Ross Fellowship from Purdue University and grants from N.I.H.]