Early imitation predicts adaptive behavior at school age: A longitudinal population-based cohort study

Imitation provides a foundation for acquiring a wide range of knowledge and skills; accordingly, early imitation may contribute to the development of later adaptive behavior encompassing conceptual, practical, and social skills. The present study examined whether imitation at 14 months predicts adaptive behavior at 8 years of age in a general population sample.

We analyzed data from the Hamamatsu Birth Cohort for Mothers and Children (HBC Study), a prospective birth cohort of children in Japan (n = 724). Adaptive behavior at 8 years of age was assessed using the Vineland Adaptive Behavior Scales, Second Edition (VABS-II), which served as the dependent variable. Hierarchical multiple regression analyses were conducted for each domain-level score of the VABS-II (communication, daily living skills, and socialization). Imitation at 14 months, assessed using the Japanese MacArthur Communicative Development Inventory, was entered as the primary predictor, along with relevant confounding variables.

The imitation score at 14 months significantly predicted all three domains of adaptive behavior at 8 years, even after controlling for covariates, including children's developmental quotient, intelligence quotient, autism spectrum disorder traits, and demographic factors. The most substantial contribution was found in daily living skills, followed by socialization and communication.

Imitation in infancy was a significant predictor of later adaptive behavior, particularly in daily living skills and socialization. These findings suggest that early imitation may be related to learning processes essential for independent and cooperative living and may offer a clinically meaningful perspective on later functional outcomes, particularly adaptive behavior.