Contribution of Two Sources of Listener Knowledge to Intelligibility of Speakers With Cerebral Palsy Purpose This study examined the independent and combined effects of two sources of linguistic knowledge (alphabet cues and semantic predictability) on the intelligibility of speakers with dysarthria. The study also examined the extent to which each source of knowledge accounted for variability in intelligibility gains. Method Eight speakers ... Research Article
Research Article  |   October 01, 2007
Contribution of Two Sources of Listener Knowledge to Intelligibility of Speakers With Cerebral Palsy
 
Author Affiliations & Notes
  • Katherine C. Hustad
    Waisman Center, University of Wisconsin–Madison
  • Contact author: Katherine C. Hustad, 475 Waisman Center, University of Wisconsin–Madison, 1500 Highland Avenue, Madison, WI 53705. E-mail: kchustad@wisc.edu.
Article Information
Speech, Voice & Prosodic Disorders / Special Populations / Genetic & Congenital Disorders / Speech / Research Articles
Research Article   |   October 01, 2007
Contribution of Two Sources of Listener Knowledge to Intelligibility of Speakers With Cerebral Palsy
Journal of Speech, Language, and Hearing Research, October 2007, Vol. 50, 1228-1240. doi:10.1044/1092-4388(2007/086)
History: Received February 3, 2006 , Revised June 26, 2006 , Accepted March 6, 2007
 
Journal of Speech, Language, and Hearing Research, October 2007, Vol. 50, 1228-1240. doi:10.1044/1092-4388(2007/086)
History: Received February 3, 2006; Revised June 26, 2006; Accepted March 6, 2007
Web of Science® Times Cited: 11

Purpose This study examined the independent and combined effects of two sources of linguistic knowledge (alphabet cues and semantic predictability) on the intelligibility of speakers with dysarthria. The study also examined the extent to which each source of knowledge accounted for variability in intelligibility gains.

Method Eight speakers with cerebral palsy and dysarthria contributed speech samples, and 128 listeners transcribed the speech samples (16 listeners per speaker) in 4 different conditions (no cues and unpredictable sentences; no cues and predictable sentences; alphabet cues and unpredictable sentences; alphabet cues and predictable sentences). Listener transcription results were the dependent variable and were scored as the percentage of words identified correctly by listeners.

Results Both alphabet cues and semantic predictability made independent and overlapping contributions to intelligibility. In addition, alphabet cues accounted for more of the variability in gain scores than semantic predictability. Inseparable joint effects from the two sources of knowledge also made an important contribution to intelligibility.

Conclusion Alphabet cues may be a more powerful source of information for resolving lexical ambiguity than semantic predictability for listeners who are faced with dysarthric speech.

Acknowledgments
This research was funded by Grant R03 DC005536 from the National Institute on Deafness and Other Communication Disorders. These data were presented at the 2005 American Speech-Language-Hearing Association Annual Convention, San Diego, CA. Thanks to Caitlin Dardis, Lisa Igl, and Jamie Weisman for assistance with collecting data from listeners and analyzing intelligibility results.
Order a Subscription
Pay Per View
Entire Journal of Speech, Language, and Hearing Research content & archive
24-hour access
This Article
24-hour access