How Do Children Organize Their Speech in the First Years of Life? Insight From Ultrasound Imaging

Purpose This study reports on a cross-sectional investigation of lingual coarticulation in 57 typically developing German children (4 cohorts from 3.5 to 7 years of age) as compared with 12 adults. It examines whether the organization of lingual gestures for intrasyllabic coarticulation differs as a function of age and consonantal context. Method Using the technique of ultrasound imaging, we recorded movement of the tongue articulator during the production of pseudowords, including various vocalic and consonantal contexts. Results Results from linear mixed-effects models show greater lingual coarticulation in all groups of children as compared with adults with a significant decrease from the kindergarten years (at ages 3, 4, and 5 years) to the end of the 1st year into primary school (at age 7 years). Additional differences in coarticulation degree were found across and within age groups as a function of the onset consonant identity (/b/, /d/, and /g/). Conclusions Results support the view that, although coarticulation degree decreases with age, children do not organize consecutive articulatory gestures with a uniform organizational scheme (e.g., segmental or syllabic). Instead, results suggest that coarticulatory organization is sensitive to the underlying articulatory properties of the segments combined.