Canonical babbling in Korean-acquiring infants at 4-9 months of age

Abstract

Objectives: Canonical babbling is a key feature of vocal development in the first year. This study aimed to examine changes in canonical babbling in Korean-acquiring infants from 4 to 9 months of age based on vocal samples obtained through all-day recordings in naturalistic environments. Methods: Language ENvironment Analysis (LENA) all-day home recordings were obtained from 13 infants aged 4-6 months and 13 infants aged 7-9 months. Twenty 5-minute segments with the highest child vocalization rate were extracted from each infant's LENA recording. The coders, who received intensive coding training, determined syllable types (canonical, non-canonical, glide, or glottal syllables) while listening to the selected recordings. The effects of age and gender were determined on the number of each syllable type and canonical babbling ratios (CBR). Results: The results indicated that infants aged 7-9 months produced significantly more canonical syllables and showed higher CBR than infants aged 4-6 months. Eight 7 to 9-month-old infants had entered canonical babbling stage. Boys produced significantly more canonical syllables and showed higher CBR than girls in this study. Conclusion: This study is the first effort to evaluate canonical babbling in Korean-acquiring infants and examine vocal development through a representative sampling of vocalizations in natural environments through day-long recordings.