Monaural envelope correlation perception in listeners with normal hearing and cochlear impairment.

Monaural envelope correlation perception was investigated in listeners with normal hearing and in listeners with cochlear hearing loss. Using a three-interval forced-choice procedure, the task of the subject was to identify the one interval out of three where the noise bands had correlated envelopes. Performance was determined as a function of the spectral separation between noise bands (delta f of 250, 500, or 1000 Hz) and the number of noise bands present (two, three, or five). Although individual differences existed, the results generally indicated better performance for the listeners with normal hearing when the delta f between bands was relatively small; however, there was no significant effect of hearing loss when the frequency separation between bands was greater than 250 Hz. The listeners with normal hearing generally showed decreased performance with increasing delta f, whereas the performance of many of the listeners with hearing impairment usually did not change appreciably with variation in delta f. Both groups of listeners showed improved performance with increasing number of noise bands present for the 500-Hz delta f. Only the listeners with hearing impairment showed significantly improved performance with increasing band number for the 250-Hz delta f; neither group showed improved performance with increasing band number for the 1000-Hz delta f. With five bands present, the performance of the listeners with hearing impairment did not differ significantly from that of the listeners with normal hearing, even for the 250-Hz delta f.(ABSTRACT TRUNCATED AT 250 WORDS)