A kinematic study of the labial and mandibular movements during production of Cantonese bilabial plosives

Abstract

This study examined the possible effects of aspiration and vowel context on labial and mandibular gestures during production of Cantonese bilabial plosives /p/ and /p^h/. Thirty adult native Cantonese speakers were recruited in the study. Participants were asked to read aloud VCV sequences upon spoken examples presented in random fashion. Kinematic data describing the movements of upper and lower lips, and lower jaw were obtained using Electromagnetic Articulography (EMA). Results revealed a significant aspiration effect on the vertical velocities of lower lip and jaw movements, and such effect was consistent across all vowel contexts. However, results did not reveal any significant aspiration effect, except some effects for vowel context in the anteroposterior displacements and velocities during upper and lower lips movements. The findings appear to confirm the hypothesis of muscular force as the main driving force in facilitating the production of unaspirated bilabial plosive /p/. Yet, the mechanism governing the lip opening for aspirated cognate /p^h/ may require further examination.