This paper presents a study of audio-visual production of the four Mandarin lexical tones on words in citation form and in sentences. OPTOTRAK motion capture data of the head and face of a Mandarin speaker were modelled using both PCA and guided-PCA. For each tone, correlations between F0 values and the different face and head components were calculated. Results show that there are visual parameters related to the different F0 patterns of each tone. Moreover differences were found in both duration and correlational patterns between words produced in citation and in sentential forms. The results show that there are identifiable visual correlates of lexical tone but the difference between citation and sentential forms has implications for materials used in production and perception studies of Mandarin lexical tones, and possibly those in other languages.
Index Terms: audiovisual speech production, tone languages, Mandarin, OPTOTRAK, motion capture.