Development of stop consonants in three- to six-year-old Mandarin-speaking children.

This study compared the temporal measurements of stop consonants in 29 three- to six-year-old Mandarin-speaking children and 12 Mandarin-speaking adults. Each participant produced 18 Mandarin disyllabic words which contained six stop consonants /p, pʰ, t, tʰ, k, kʰ/ each followed by three vowels /a, i, u/ at the word-initial position in the first syllable. The temporal measurements of VOT, overall burst duration, average duration per burst, number of bursts, and VOT-lag duration were obtained. Although adult-like short-lag VOTs were achieved in all children, the long-lag VOTs were widespread in the younger group and gradually developed to a concentrated distribution in the older children. Further analysis of the burst and VOT-lag revealed that these children tended to produce shorter average duration per burst and longer VOT-lag than the adults. These results indicate that children in this age range may not have developed adult-like laryngeal-oral timing pattern and airflow control for stop production.