A Longitudinal Examination of Parent-Child Interaction in the Context of Toddlers at High-Risk of Autism

Background: Dyadic interaction can be challenging in the context of Autism Spectrum Disorder (ASD), for children and their social partners alike. Children with ASD initiate little and their parents often adopt more directive/asynchronous rather than responsive/synchronous interaction styles. Individual variability in parental contributions seem to be important, as increased parental responsiveness/synchrony has been shown to facilitate the development of child social-communication skills (e.g., Green et al., 2010; Siller & Sigman, 2002). Little is yet known, however, about the mechanisms and trajectories underlying the development of dyadic interaction styles for parents and their toddlers who are developing ASD. 

Objectives:   Within a familial ASD-risk design, the current study evaluated parent-child dyadic communication around the 1^st, 2^nd and 3^rd birthdays of 100 toddlers. The aim was to determine at what developmental point and in what order/sequence parent and child contributions might become differentiated for groups including toddlers developing ASD vs. toddlers following more typical trajectories.

Methods:   Among the 100 parent-child dyads, 52 toddlers were considered to be at familial high-risk (HR) of ASD (due to having an older sibling with the diagnosis) while 48 were at low-risk (LR). Among HR toddlers, 17 were confirmed to have ASD by 3-years of age (HR-ASD), while 12 presented other developmental atypicalities (HR-Atypical) and 23 were typically developing (HR-Typical). At each of three visits, around toddler ages of 14, 24, and 38 months, parent-child interaction footage and standardised child developmental assessments were collected. Eight-minute interaction clips were later coded by blinded research assistants, for the following key measures; a) frequencies of parent synchronous and asynchronous communication acts, and b) frequencies of child initiation and response acts, based on the Dyadic Communication Measure for Autism (DCMA; Hudry et al., 2013). As per the DCMA procedure, proportionate scales were then computed from these raw codes, representing the relative balance of Parent Synchronous contributions and of Child Initiations.

Results:  

Child Initiations increased significantly across toddlerhood for all groups. HR-ASD toddlers, however, contributed significantly fewer initiations than LR toddlers at around the 2^nd and 3^rd birthdays, with the initiated contributions of HR-Typical toddlers also significantly reduced around the 2^nd birthday, but HR-Typical and HR-Atypical toddlers falling intermediate to HR-ASD and LR toddlers around the 3^rd birthday. Parent Synchrony also showed changes across the toddlerhood period, increasing between toddlers’ 2^nd and 3^rd birthdays. At a group level, however, this increase in Synchrony was not apparent for parents of HR-ASD toddlers, who remained relatively more asynchronous.

Conclusions:   While children with ASD increased their initiated contributions across toddlerhood, increases were less pronounced than for other children, with differences apparent from the second birthday. Furthermore, parents of children with ASD failed to show a normative increase in relative synchrony between their toddlers’ second and third birthdays. These findings provide downward extension from past research on children with established diagnoses, and suggest that early differentiation of child interaction behaviours precedes any differentiation of parent contributions. This provides an important step toward delineating how parent-child interaction is shaped in the context of toddlers developing ASD.