The relationship between pure-tone sequential stream segregation and perceptual separation of male and female talkers by listeners with hearing loss

The purpose of this study was to describe the relationship between sequential stream segregation abilities of listeners with hearing loss and the ability to recognize pairs of sentences spoken simultaneously by a man and a woman. In the streaming task, the fusion threshold was measured as the frequency separation at which listeners could no longer perceptually separate a series of fixed and varying-frequency pure-tones. The varying frequency tones started at frequencies either below (ascending) or above (descending) the frequency of the fixed tone. Seven of 11 subjects showed significant differences between the ascending and descending fusion thresholds. Ascending fusion thresholds were found to predict the intelligibility of the male talker, but not the female talker. Conversely, descending fusion thresholds were found to predict the intelligibility of the female talker, but not the male talker. In both cases, higher speech perception scores were associated with lower (better) fusion thresholds.