Longitudinal Study of Early Vocalization Development in Toddlers with and without Cleft Palate from 6 to 18 Months of Age
Communication Sciences & Disorders
Objectives: Early vocalization shows a close relationship with speech sound development and influences the onset of first words. This study explored longitudinally early vocalization development in toddlers with and without cleft palate from 6 to 18 months of age. Methods: The participants included 3 toddlers with cleft palate and 3 typically developing toddlers. Their vocalization samples were obtained with 3-month intervals from 6 or 7 to 18 months of age. The vocalization samples were
... d based on the Stark assessment of early vocal development-revised and measures on vocalization types and each vocalization ratio were obtained. Results: Results indicated that group differences were observed in the ratio of level 2 at 18 months of age; toddlers with cleft palate exhibited a larger ratio of level 2 vocalization at 18 months of age. Two toddlers with cleft palate showed delayed vocalization developmental patterns during the entire period of the study. Toddlers with cleft palate showed decreases in level 2 which includes fully-resonant nuclei and two closant-vocant combinations. However, they did not exhibit remarkable changes in level 4 and 5 which include single consonant-vowel syllable, repeated canonical syllable, and jargon. Typically developing toddlers showed decreases in level 2 vocalization and progressive increases in level 4 and 5. Conclusion: This study suggested that toddlers with cleft palate generally showed delayed vocalization development compared to typically developing toddlers. The study results have implications for monitoring the development of pre-linguistic vocalization in toddlers with cleft palate.