The Speech Regulating System Temporal and Aerodynamic Responses to Velopharyngeal Inadequacy Research Article
Research Article  |   September 01, 1989
The Speech Regulating System
 
Author Affiliations & Notes
  • Donald W. Warren
    The Dental Research Center and the Department of Dental Ecology, School of Dentistry and the Department of Surgery, School of Medicine, University of North Carolina at Chapel Hill
  • Rodger M. Dalston
    Dental Research Center and the Department of Surgery, School of Medicine, University of North Carolina at Chapel Hill
  • Kathleen E. Morr
    Department of Dental Ecology and the Dental Research Center, University of North Carolina at Chapel Hill
  • W. Michael Hairfield
    Department of Dental Ecology and the Dental Research Center, University of North Carolina at Chapel Hill
  • Lynn R. Smith
    Department of Dental Ecology and the Dental Research Center, University of North Carolina at Chapel Hill
Article Information
Research Articles
Research Article   |   September 01, 1989
The Speech Regulating System
Journal of Speech, Language, and Hearing Research, September 1989, Vol. 32, 566-575. doi:10.1044/jshr.3203.566
History: Received May 23, 1988 , Accepted November 15, 1988
 
Journal of Speech, Language, and Hearing Research, September 1989, Vol. 32, 566-575. doi:10.1044/jshr.3203.566
History: Received May 23, 1988; Accepted November 15, 1988

Temporal and respiratory responses to a loss of velar resistance were measured in 107 subjects demonstrating varying degrees of velopharyngeal inadequacy. The subject data were compared to data generated by a mechanical model representing a passive system. The pressure-flow technique was used to estimate velopharyngeal orifice size and measure respiratory and temporal characteristics of aerodynamic events associated with the production of the nasal-plosive blend/mp/in the word "hamper". Subjects were categorized as having adequate closure (<0.05 cm2), adequate/borderline closure (0.05–0.09 cm2), borderline/ inadequate closure (0.10–0.19 cm2) and inadequate closure (⩾ 0.20 cm2).

The data revealed that intraoral pressure fell 10-fold in the model as velopharyngeal orifice area changed from adequate closure to inadequate. The subject data demonstrated only a 1.4-fold drop in pressure. Airflow data indicated that there was a 10-fold increase in respiratory volume in the subject data corresponding to the change from adequacy to inadequacy. When respiratory and temporal responses were assessed together, the findings revealed that airflow and temporal changes minimized the fall of pressure as velar resistance declined across groups.

Order a Subscription
Pay Per View
Entire Journal of Speech, Language, and Hearing Research content & archive
24-hour access
This Article
24-hour access