Abstract
Children’s early language environments are associated with linguistic, cognitive, and academic development, as well as concurrent brain structure and function. This study investigated neurodevelopmental mechanisms linking language input and development by measuring neuroplasticity associated with an intervention designed to enhance language environments in lower-income families. Families of 52 4-to-6 year-old children were randomly assigned to a 9-week, interactive, family-based intervention or no-contact control group. Children completed pre- and post-assessments of verbal and nonverbal cognition, structural magnetic resonance imaging, and two days of auditory recordings to measure language exposure. Families who completed the intervention exhibited a greater increase in the number of adult-child conversational turns. Turn-taking changes correlated positively with changes in verbal, nonverbal, and executive functioning measures, as well as cortical thickening in left inferior frontal and supramarginal gyri, the latter of which mediated the relationship between changes in conversational turns and language scores. This is the first study to investigate longitudinal neuroplasticity in response to changes in children’s language environments and suggests that conversational turns support language development through cortical growth in language and social processing regions. This has implications for early interventions to enhance young children’s language environments, including family-support programs and addressing systemic barriers to family communication.
Competing Interest Statement
The authors have declared no competing interest.