Gesture in Toddlers with Autism Spectrum Disorder: Before and after Intervention

Background:  Young children with autism spectrum disorders (ASD) exhibit impaired gesture development (APA, 2013; Landa, 2007). Gesture is an essential component of social interaction. Also, gesture can be used to compensate for spoken language limitations (e.g., typically-developing toddlers, and children with language delay; Capone & McGregor, 2004) and can index and facilitate learning (Goldin-Meadow, 2009). For these reasons, gesture is an important aspect of communication to target in early interventions for ASD. 

Objectives:  We investigated gesture production in toddlers who participated in a previously reported intervention for ASD (Landa et al., 2011). We predicted that across the entire sample gesture production would increase from pre-test to post-test. However, gains in mature gesture use, including pointing gestures, would only be observed for the treatment group. 

Methods:  Toddlers (mean age=31.06 months, SD=6.08) with ASD participated in a six-month randomized-controlled-trial targeting social and communication skills. In both groups, caregivers were coached in the implementation of evidence-based child-responsive strategies.  In only one condition, however, this intervention was supplemented with nursery school classroom-based instruction (class) treatment condition where they received an interpersonal synchrony curriculum and instruction fostered peer-to-peer engagement.  Here, we report on nine children in each condition.  There were no significant differences between groups for age (p=.69), general developmental level on the Mullen Scales of Early Learning (MSEL) (p=.79), MSEL Expressive Language (p=.730), nor on any of our outcome measures (p’s>.63) at baseline. The Autism Diagnostic Observation Schedule (ADOS, Lord et al., 2000) was administered to all children before and after the intervention. Coders blind to condition coded communicative gesture production during the sections of the ADOS that are included in the modules used here (T, 1, 2) (e.g., free-play). We derived three measures of gesture based on developmental maturity and importance in ASD (Iverson, et al., 1994; Kita, 2003, Wetherby et al., 2004). Measures included: (1) number of developmentally mature gestures produced (e.g., pointing gestures, waving goodbye, holding an object up to show to someone); (2) number of developmentally immature gestures produced (e.g., extending an object for someone to take); and (3) number of pointing gestures. Measures (1) and (2) are mutually-exclusive. Due to small sample size, we used non-parametric tests when possible, although results are unchanged when using parametric alternatives.

Results:  We found significant increases in mature gestures (p=.016) and pointing gestures (p=.049), but not immature gestures (p=.399) from pre- to post-test in both groups (Figure 1). However, consistent with our predictions, effects varied with condition. Two-factor repeated-measure ANOVAs revealed a significant interaction between session (pre-test, post-test) and condition for mature gestures (F=5.36, p=.038) and pointing gestures (F=4.77, p=.048), but not immature gestures. At post-test, children in the treatment group produced more mature gestures and more pointing gestures than the control group (p=.024 and p=.019, respectively). In contrast, the control group produced relatively more immature gestures (p=.050) (Figure 2). 

Conclusions:  Intervention is associated with increased frequency and maturity of communicative gesture in toddlers with ASD. These effects may have cascading consequences for positively impacting and enriching social interactions for children with ASD.