Child Language and Autism Diagnosis Impact Hierarchical Temporal Structure of Parent-Child Vocal Interactions in Early Childhood

Abstract

Timing is critical to successful social interactions. This study investigated temporal structure of vocal interactions longitudinally in parent-child dyads of typically developing (TD) infants (n=49; 9-18 months; 48% male; 81.6% white) and toddlers with ASD (n=23; 27.2±5.0 months; 91.3% male; 65.2% White). Acoustic hierarchical temporal structure (HTS; event clustering across multiple time scales), which reflects temporal complexity and variability, was measured in free play interactions using Allan Factor. Child expressive language significantly predicted HTS (ß=-0.2) longitudinally across TD infants: greater dyadic HTS was associated with lower child language. ASD dyads exhibited greater HTS than nonverbal matched (d=0.41) and expressive language matched TD dyads (d=0.28). Results provide a new window into how language development and social attunement shape parent-child interaction dynamics.