Effect of Consonant-Vowel Ratio Modification on Amplitude Envelope Cues for Consonant Recognition This investigation examined the degree to which modification of the consonant-vowel (C-V) intensity ratio affected consonant recognition under conditions in which listeners were forced to rely more heavily on waveform envelope cues than on spectral cues. The stimuli were 22 vowel-consonant-vowel utterances, which had been mixed at six different signal-to-noise ... Research Article
Research Article  |   April 01, 1991
Effect of Consonant-Vowel Ratio Modification on Amplitude Envelope Cues for Consonant Recognition
 
Author Affiliations & Notes
  • Richard L. Freyman
    Department of Communication Disorders University of Massachusetts
  • G. Patrick Nerbonne
    Department of Communication Disorders University of Massachusetts
  • Heather A. Cote
    Department of Communication Disorders University of Massachusetts
  • Requests for reprints may be sent to Richard L. Freyman, Department of Communication Disorders, University of Massachusetts, 6 Arnold House, Amherst, MA 01003.
Article Information
Hearing / Research Articles
Research Article   |   April 01, 1991
Effect of Consonant-Vowel Ratio Modification on Amplitude Envelope Cues for Consonant Recognition
Journal of Speech, Language, and Hearing Research, April 1991, Vol. 34, 415-426. doi:10.1044/jshr.3402.415
History: Received January 8, 1990 , Accepted July 13, 1990
 
Journal of Speech, Language, and Hearing Research, April 1991, Vol. 34, 415-426. doi:10.1044/jshr.3402.415
History: Received January 8, 1990; Accepted July 13, 1990

This investigation examined the degree to which modification of the consonant-vowel (C-V) intensity ratio affected consonant recognition under conditions in which listeners were forced to rely more heavily on waveform envelope cues than on spectral cues. The stimuli were 22 vowel-consonant-vowel utterances, which had been mixed at six different signal-to-noise ratios with white noise that had been modulated by the speech waveform envelope. The resulting waveforms preserved the gross speech envelope shape, but spectral cues were limited by the white-noise masking. In a second stimulus set, the consonant portion of each utterance was amplified by 10 dB. Sixteen subjects with normal hearing listened to the unmodified stimuli, and 16 listened to the amplified-consonant stimuli. Recognition performance was reduced in the amplified-consonant condition for some consonants, presumably because waveform envelope cues had been distorted. However, for other consonants, especially the voiced stops, consonant amplification improved recognition. Patterns of errors were altered for several consonant groups, including some that showed only small changes in recognition scores. The results indicate that when spectral cues are compromised, nonlinear amplification can alter waveform envelope cues for consonant recognition.

Acknowledgments
The authors would like to thank Kelly J. Shea for her assistance in collecting and analyzing data and Arthur Boothroyd and Kenneth Grant for helpful reviews. This research was supported by a grant from the Whitaker Foundation.
Order a Subscription
Pay Per View
Entire Journal of Speech, Language, and Hearing Research content & archive
24-hour access
This Article
24-hour access