Measuring larynx movement in standard Thia using the cricothyrometer.

Vertical movement of the larynx during connected speech was investigated in Standard Thai - a language that has five phonologically contrastive tones. The effects of pitch, consonant phonation-type, vowel quality, tonal categories, and position in the utterance were determined. Utterance position was found to be the factor most clearly associated with variations in larynx movement. The occurrence of an overall rise-fall pattern of larynx movement distributed over utterances of varying pitch patterns leads to the conclusion that larynx height is not a principal factor regulating pitch in connected speech. Implications for models of pitch production, distinctive features for tone, theories on the historical development of tone and the role of larynx movements in the production of consonants and vowels are discussed.