Effect of speech rate on lip aperture, tongue tip and tongue dorsum kinematics during production of Cantonese plosives

Abstract

The present study investigated the effect of speech rate on kinematics of lip aperture, tongue tip and tongue dorsum by examining the direct kinematic data of Cantonese plosives produced at different speech rate. Aspirated and unaspirated bilabial, alveolar and velar plosives (/ph/, /p/, /t/, /th/, /k/ and /kh/) were produced at three speech rates (one syllable per second, three syllables per second and as fast as possible) by ten male and ten female native adult speakers of Cantonese. By using electromagnetic articulography (EMA), movements of the upper lip, lower lip, tongue tip and tongue dorsum were measured. The kinematic data revealed that faster speech rate was associated with shorter release displacement of articulators. This finding was in line with results previously reported on English. Besides, speech rate was also found associated with increase of articulator velocity in different degree among different plosives. In addition, interaction between aspiration and speech rate was revealed. The results shown that aspiration interacted with speech rate differently for different plosives. Further investigations in kinematics and aerodynamics on the effect of aspiration are suggested in order to draw a more concrete conclusion for aspiration effect.