Abstract
The role of auditory feedback in speech production was investigated by examining speakers' phonemic contrasts produced under increases in the noise to signal ratio (N/S). Seven cochlear implant users and seven normal-hearing controls pronounced utterances containing the vowels /i/, /u/, /ε/ and /æ/ and the sibilants /s/ and /ʃ/ while hearing their speech mixed with noise at seven equally spaced levels between their thresholds of detection and discomfort. Speakers' average vowel duration and SPL generally rose with increasing N/S. Average vowel contrast was initially flat or rising; at higher N/S levels, it fell. A contrast increase is interpreted as reflecting speakers' attempts to maintain clarity under degraded acoustic transmission conditions. As N/S increased, speakers could detect the extent of their phonemic contrasts less effectively, and the competing influence of economy of effort led to contrast decrements. The sibilant contrast was more vulnerable to noise; it decreased over the entire range of increasing N/S for controls and was variable for implant users. The results are interpreted as reflecting the combined influences of a clarity constraint, economy of effort and the effect of masking on achieving auditory phonemic goals—with implant users less able to increase contrasts in noise than controls.
Keywords
speech processing, hearing aids
Subject Categories
Speech perception, Cochlear implants, Postlingual deafness, Hearing, Voice
Disciplines
Psychology | Speech and Hearing Science
Publisher
Acoustical Society of America
Publication Date
1-1-2007
Rights Information
This article may be downloaded for personal use only. Any other use requires prior permission of the author and the Acoustical Society of America.
Rights Holder
©2007 Acoustical Society of America
Permanent URL
Recommended Citation
Perkell, Joseph S.; Denny, Margaret; Lane, Harlan; Guenther, Frank; Matthies, Melanie L.; Tiede, Mark; Vick, Jennell; Zandipour, Majid; and Burton, Ellen, "Effects of masking noise on vowel and sibilant contrasts in normal-hearing speakers and postlingually deafened cochlear implant users" (2007). Psychology Faculty Publications. Paper 8. http://hdl.handle.net/2047/d20000877
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Notes
The following article appeared in J. Acoust. Soc. Am. Volume 121, Issue 1, pp. 505-518 (January 2007) and may be found at http://dx.doi.org/10.1121/1.2384848