Interaction between pitch control and articulatory mechanisms

Abstract

Movements of articulatory organs influence laryngeal function in various ways and may change vocal fold tension, and movements of the articulators may also result from pitch control. Since the mechanisms for pitch control and articulation use some of the same structures, they interact. In a previous report, we noted that forward movement of the hyoid bone, produced by genioglossus activity for a high vowel and geniohyoid activity for high pitch, participated in increasing fundamental frequency. Hyoid bone movement during speech influences vocal fold tension and provides a supplementary tensor mechanism. In this study, we report cinefluorographic observations on two American English speakers with simultaneous EMG measurements from the genioglossus. The vowels /a/, /i/, and /u/ were pronounced in /kaCVC/ utterances with different stress patterns. Hyoid bone position, epiglottis position, and genioglossus muscle activity were compared across changes in vowel identity, consonant environment, and stress pattern. The relationship between these measures and fundamental frequency variations were used to further explore the nature of interaction between pitch control and speech articulation. [Work supported by NINCDS.]