The Function of the Epiglottis in Speech

Abstract

We have investigated the movements of the epiglottis in speech by speakers of Hebrew. The epiglottis functions as an articulator in the production of pharyngeal consonants and in the vowel /a/. It is also involved in whisper. In pharyngeals, the epiglottis articulates against the posterior pharyngeal wall; the constriction varies from a full closure (pharyngeal stop) in some examples of /?/ in slow careful speech, through a narrow opening for the fricatives /h/ and other examples of /?/ in connected speech, to a fairly open glide in yet other examples of /?/ in rapid or casual style. In the vowel /a/, the opening between the pharynx and the epiglottis is of the same general shape as for the pharyngeal consonants, but larger. In the case of both consonants and /a/, however, the size of the opening is never large enough to pull the lateral edges of the epiglottis away from the posterior pharyngeal wall. That is, air passes only through a passage bounded by the epiglottis and the pharynx, and never escapes along the tongue root lateral to the epiglottis. The epiglottis folds toward the pharyngeal wall independently of the tongue root in consonants; this independence is seen in some cases of /a/ and not others; in whisper, the epiglottis is generally more retracted than in normal speech but otherwise moves as usual. Our conclusions are based on 100 minutes of videotape made using a fiberscope positioned in the upper pharynx, spectrograms, and dissections. We conclude that the epiglottis is an active, independent, and acoustically significant articulator.