4pPP10. Role of fundamental frequency differences in perception of simultaneous vowels by hearing-impaired listeners.

Session: Thursday Afternoon, May 16

Author: Kathryn Hoberg Arehart
Author: Catherine Arriaga King
Author: Kelly S. McLean
Location: CDSS Dept., Univ. of Colorado, CB 409, Boulder, CO 80309


This study investigated the ability of normal-hearing listeners and listeners with moderate to moderately severe sensorineural hearing loss to use differences in fundamental frequency (F[inf 0]) in the identification of monotically presented simultaneous vowels. Two psychophysical procedures, masked vowel identification and double-vowel identification, were used to measure identification performance as a function of F[inf 0] differences (0 through 12 semitones) between simultaneous vowels. The masked vowel identification task yielded thresholds representing signal-to-noise ratios at which listeners could just identify target vowels in the presence of a masking vowel. Performance in the double-vowel identification task was measured by the percentage of trials in which listeners correctly identified both vowels in a double vowel. As previously reported, normal-hearing listeners showed a sharp increase in the ability to separate simultaneous vowels as F[inf 0] differences increased from 0 to 1 semitone. Hearing-impaired listeners were less effective in using F[inf 0] differences in the perception of simultaneous vowels. Reasons for hearing-impaired listeners' reduced performance probably include differences in their ability to use spectral and temporal cues across different frequency regions in their perception of complex-tone pitch. [Work supported by Deafness Research Foundation.]

from ASA 131st Meeting, Indianapolis, May 1996