Abstract:
Labeling of concurrently presented vowels generally improves with the F0 difference between vowels (up to a limit of 2 to 4 semitones difference). One interpretation of this finding is that the processing of F0 differences between vowels allows listeners to group spectral components according to a common fundamental and thereby improve identification. However, the benefit of F0 differences may be reduced for hearing-impaired listeners to the extent that accuracy in processing F0 is compromised by the sensory impairment. In this study, normal-hearing and hearing-impaired listeners were tested to determine F0 difference limens for synthetic tokens of five steady-state vowels. The same stimuli were then used in a concurrent-vowel labeling task. Preliminary results indicate accurate processing of F0 differences between vowels, with thresholds generally below 2.0 Hz across vowels and listeners. On concurrent-vowel data collected thus far, hearing-impaired listeners showed an overall reduction in labeling accuracy relative to normal-hearing listeners. However, the benefit to labeling associated with F0 differences between vowels was of similar magnitude across groups. Additional subjects are being tested and analyses correlating performance on the F0 task with F0-benefit on the labeling task will be reported. [Work supported by NIH.]