Background: Early intervention (EI) has the potential to dramatically improve long-term outcomes in children with ASD (Howlin, Magiati, & Charman, 2009). Little is known about the influence of child-level characteristics on treatment gains in different EI settings, which could have important implications for how we match children to the most effective setting. Language may be an important moderator of individual gains. For example, a study of preschoolers with ASD revealed that children with higher standardized language scores at the beginning of the school year demonstrated steeper rates of cognitive growth in inclusion classrooms than in mixed disability or inclusion classrooms (Nahmias et al., 2014). In this study, we explore a hallmark of social communication: conversational turn-taking (Dykstra et al., 2013; Warren et al., 2010). Conversational turn-taking is a dynamic, ecologically valid measure of social communication that may vary across different EI settings. Defining child and classroom factors that facilitate conversational turn-taking could guide placement decisions, particularly if more turn-taking results in greater long term social and cognitive growth.
To assess conversational turn-taking in preschoolers with ASD, their teachers, and their peers during free play in three EI classroom settings (autism-only, mixed disability, inclusion), and compare profiles of children who engaged in peer conversations with children who did not.
Twenty-four preschoolers with ASD (16 boys, M=4.1 years, 88% scored “very low” on the Mullen ELC) wore t-shirts with digital language recorders (LENA) in a child-safe chest pocket during a typical school day. All verbalizations produced by or directed at the target child during an unstructured “free play” sample were orthographically transcribed (M=19.0 minutes). We defined conversational turns as pauses of greater than 0 seconds and less than 4 seconds between utterances by different speakers (target child, peer, teacher). Dependent variables included turn-taking rates relative to total recording duration and inter-turn latency.
All 24 participants engaged in conversational turn-taking with teachers, but only 38% conversed with their peers. Children who engaged in peer conversational turn-taking (PC) were more likely than those who did not (N-PC) to be in inclusion classrooms (Chi-square = 7.22, p<.05), and in classrooms with more students (p<.05). PC and N-PC had statistically equivalent SCQ and ADOS severity scores, but PC had higher Mullen expressive and receptive language scores than N-PC (ps<.05). Rates of teacher-participant conversational turn-taking did not differ by setting, and teachers responded equally quickly to children in both groups.
This exploratory study is part of a larger, longitudinal effort to examine mediators and moderators of intervention response in preschoolers with ASD, and is one of the first to analyze fine-grained measures of conversational turn-taking in different EI settings. Our finding that more peer conversations occur in inclusion classrooms suggests enriched opportunities for peer interaction in that setting compared with autism-only and mixed disability classrooms, but children in inclusion classrooms also had higher baseline standardized language scores. Future analyses with additional participants will assess the differential effects of child/classroom language variables (including conversational turn-taking) on cognitive and social growth over 9 months.