Longitudinal Study of Vocal Development and Language Environments in Infants With Cleft Palate.

OBJECTIVE: This study investigated vocalization and language environment longitudinally in infants with cleft palate (CP) based on day-long audio recordings collected in their natural environments. DESIGN: Language Environment Analysis (LENA) data from all-day recordings at home were collected at 3-month intervals for infants from 4-6 to 16-18 months of age. The recordings were analyzed using experimentally blinded human coding as well as LENA automated analysis. PARTICIPANTS: Ten infants with CP (± cleft lip) and 10 age-matched infants without CP. MAIN OUTCOME MEASURES: Several measurements were obtained from the LENA automated analysis software. In addition, human coded measurements of vocalization and language environment, including the true canonical babbling ratio and the infant-directed speech ratio, were analyzed for each time point of data collection for each infant. Statistical analyses were performed to conduct group and age comparisons for each measure of vocalization and language environment. RESULTS: No group differences emerged in number of syllables produced. Infants with CP exhibited late onset and fewer productions of canonical syllables compared to infants without CP. Infants with CP did not show significant differences from infants without CP in measures related to language environment across ages. CONCLUSION: This study provides detailed information through naturalistic all-day home recordings about vocal development and early language environments in infants with CP before and after palatal repair. Clinical implications for early intervention are discussed.

Cross-linguistic comparison of utterance shapes in Korean- and English-learning children: An ambient language effect.

This study compared vocal development in Korean- and English-learning infants and examined ambient-language effects focusing on predominant utterance shapes. Vocalization samples were obtained from 14 Korean-learning children and 14 English-learning children, who ranged in age from 9 to 21 months, in monolingual environments using day-long audio recordings. The analyzers, who were blind to participants' demographic information, identified utterance shapes to determine functional vocal repertoires through naturalistic listening simulating the caregiver's natural mode of listening. The results showed no cross-linguistic differences in the amount of vocal output or the proportion of canonical syllables. However, the infants from the two language backgrounds showed differences regarding the predominant canonical utterance shapes. The percentage of VCV utterances in Korean-learning children was higher than in English-learning children while CV syllables predominated in the English-learning children. We speculate that the difference between the predominant utterance shapes of Korean- and English-learning children could be associated with differences in early lexical items typically acquired in the two language groups.