Changes in Voice Fundamental Frequency Following Discharge of Single Motor Units in Cricothyroid and Thyroarytenoid Muscles This investigation was designed to measure voice F0 changes related to single motor unit (SMU) contractions in the cricothyroid and thyroarytenoid muscles. Four subjects (3 men and 1 woman) were recorded producing a prolonged vowel at modal pitch and loudness levels while simultaneous recordings of electromyograms (EMG) from the muscles ... Research Article
Research Article  |   December 01, 1987
Changes in Voice Fundamental Frequency Following Discharge of Single Motor Units in Cricothyroid and Thyroarytenoid Muscles
 
Author Affiliations & Notes
  • Charles R. Larson
    Northwestern University, Evanston, IL
  • Gail B. Kempster
    Northwestern University, Evanston, IL
  • Michael K. Kistler
    Northwestern University, Evanston, IL
Article Information
Research Articles
Research Article   |   December 01, 1987
Changes in Voice Fundamental Frequency Following Discharge of Single Motor Units in Cricothyroid and Thyroarytenoid Muscles
Journal of Speech, Language, and Hearing Research, December 1987, Vol. 30, 552-558. doi:10.1044/jshr.3004.552
History: Received July 3, 1986 , Accepted April 13, 1987
 
Journal of Speech, Language, and Hearing Research, December 1987, Vol. 30, 552-558. doi:10.1044/jshr.3004.552
History: Received July 3, 1986; Accepted April 13, 1987

This investigation was designed to measure voice F0 changes related to single motor unit (SMU) contractions in the cricothyroid and thyroarytenoid muscles. Four subjects (3 men and 1 woman) were recorded producing a prolonged vowel at modal pitch and loudness levels while simultaneous recordings of electromyograms (EMG) from the muscles were obtained. Voice F0 changes unrelated to SMU firings in the muscles were eliminated using an averaging method previously described by Baer (1979). Results indicate that the time between discharge of the SMU and the peak in F0 Change ("F0 Latency") was variable and ranged from 5 to 20 ms for the thyroarytenoid and 6 to 75 ms for the cricothyroid muscle. Distinct oscillations in F0 were always present in recordings from the woman subject and from the men when they phonated at higher-than-modal pitch levels. The findings are discussed in relation to SMU contraction times, biomechanics of the vocal folds, and the presence of jitter in normal voices.

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