Abstract:
Variation in the pattern of vocal fold vibration associated with changes in the prosodic conditions was observed by using a high-speed digital image recording system. A new image recording system (4500 frames per second with 256x256 pixels) combined with a flexible fiberscope and an image intensifier made it possible to record laryngeal images during running speech with better time and space resolution than the previous system. Vocal fold vibrations at an initial part and at a later part in the intonational phrases showed a difference in that the vibration at a later part tends to show shorter closed phase and slower closing movement, indicating weaker excitation in the voice source. It was also revealed that the cessation of vocal fold vibration at the end of an utterance generally takes place without the abductive movement. Abductive movement takes place shortly after the voicing cessation. It is speculated that the adduction of the vocal fold and/or the changes in the subglottal conditions are taking place for the voicing cessation which may be associated with the frequent sharp drop of the pitch at the end of the utterances.