Control of the oral release in bilabial stop consonant production

Abstract

This study examines kinematic patterns of lip and jaw movements in bilabial stop production at the release of the oral closure. Lip and jaw movements were recorded using a magnetometer system. Five subjects participated and produced 50 tokens of the sequences /aCV/, where C was either /p/ or /b/ and V one of /i, a, u/. The organization of jaw movements differed between subjects. In two of the subjects, the jaw did not reach any peak position during the stop but moved continuously during the stop to a peak position during the following vowel; this was the case when the second vowel was one of /i, u/. The open vowel /a/ was reliably associated with a jaw lowering movement of greater amplitude and velocity than the vowels /i, u/. The onset of the lower lip release movement generally occurred before the onset of the jaw lowering movement. The peak velocity of both the lower lip and jaw release movement sometimes occurred before the release of the oral closure. Stop consonant voicing had no consistent influence on the release movements of the lips and the jaw, nor on a derived measure of lip aperture. [Work supported by NIH.]