Dyadic Coordination of Vocalizations and Pauses in Autistic Children and their Caregivers

Thesis (Ph.D.)--University of Washington, 2023There is emerging evidence that infants with autism spectrum disorder (ASD) demonstrate differences in dyadic coordination of vocalization and pauses with their caregivers throughout infancy and childhood compared to neurotypical children (Northrup et al, 2015; Seidl et al., 2018; Warlaumont et al., 2014). In fact, reduced dyadic coordination of vocalization characterized as larger differences in latency to respond to one another (i.e., latency difference) and overlapping vocalizations were observed to be associated with later receptive and expressive language delays in neurotypical and neurodiverse infant-caregiver dyads (Northrup & Iverson, 2015). However, dyadic coordination and its relationship to language in older, school-age autistic children are poorly understood. The current study investigated dyadic coordination variables (child and caregiver’s percent overlapping speech, latency difference) and conversational state variables (frequency and mean duration of vocalizations and pauses) in dyads of autistic or typically developing school-age children with their caregivers engaged in parent-child-play sessions in the home environment. Results showed that autistic children’s vocalization and within-speaker pauses (i.e., pauses between vocalizations made by the same speaker) were significantly less compared to typically developing children. No group differences were observed in caregivers’ percent overlapping speech or conversational state variables. One dyadic coordination variable, latency difference, significantly and uniquely predicted concurrent receptive vocabulary size, but was not a reliable predictor of composite language scores. Contrary to previous findings, latency difference was positively associated with concurrent language abilities in school-age children. These findings suggest that dyadic coordination variables present differently in older school-age children engaged in parent-child play sessions compared to infant-caregiver dyads or dyads engaged in structured tasks