With support from the National Science Foundation, Ms. Puisan Wong will carry out a dissertation project in China to investigate preschool-aged children's production of Mandarin lexical tones, under the direction of Dr. Winifred Strange. Lexical tone is an essential component in most of the world's languages; however, little is known about children's development of tone. Therefore, tone is usually neglected in theories of phonological development. Mandarin has four lexical tones; each tone is manifested by a different pitch contour and is used to differentiate words. In longer words and continuous speech, the tones change their structure, a phenomenon referred to as co-articulation. Ms. Wong's previous research on Chinese children growing up in the USA as Mandarin speakers showed that 3-year-olds had still not mastered the production of all four tones even in one-syllable words. Questions remain about whether exposure to English might have delayed these children's development of Mandarin tones.
This dissertation project will provide a baseline for tone development by children who live in a completely Mandarin-speaking environment, and extend the previous study to ask how children produce tones in longer utterances where coarticulation changes the structure of the pitch contours. The findings will help establish the milestones of phonological development in Chinese children, which will be important in the evaluation and treatment of phonological disorders in Chinese-speaking children living in the USA. The results will also contribute to our basic understanding of physiological and/or perceptual constraints on phonological development in children. The project will foster scientific collaboration between researchers in China and the USA.