The Development of Co-Speech Gesture and Its Semantic Integration with Speech in Six- to 12-Year-Old Children with Autism Spectrum Disorders
Children gesture when they talk. Co-speech gestures are spontaneous hand movements accompanying speech (McNeill, 1992). Initially, children gesture to reinforce the semantic information conveyed in speech (“cookie” while pointing to a cookie), followed by disambiguating speech (“I like this” while pointing to a cookie) and supplementing speech (“I eat” while pointing to a cookie). In early childhood, disambiguating and supplementary gestures are produced more often than reinforcing gestures (e.g., Pizzuto & Capobianco, 2005).
Young children with autism spectrum disorders (ASD) have slow understanding and development of gestures (e.g., Mastrogiuseppe et al., 2014). Previous work leaves open the question of whether school-aged children with ASD (aged six to 12) still have delay in producing gestures compared to their typically developing (TD) peers and whether they integrate speech and gesture in their speech production.
This study examined gestural production among school-aged children in a naturalistic context and how their gestures are semantically related to the accompanying speech.
Sixteen Chinese-speaking children diagnosed with ASD (two female; aged from 6.93 to 12.15), and 14 age- and IQ-matched TD children (eight female; aged from 6.38 to 11.58) participated this study.
Caregivers interacted naturally with the children. A farm blocks play set was provided to facilitate communication. All conversations between children and caregivers and their gestures (iconic gestures; pointing gestures; emblems; speech beats) were transcribed by Chinese-speaking research assistants.
On average, children with ASD produced 5.13 gestures of all types (SD=4.24), and TD children produced 17.50 gestures of all types (SD=10.29), U=29.50, p<.001. Among different types of gesture, TD children produced a significantly higher proportion of markers (e.g., CLAPPING HANDS referring to happiness) than children with ASD, U=50, p<.01. Table 1 shows the results of different types of gesture in both groups of children.
We then examined the semantic relation between speech and gesture by looking at the utterances combining speech and gesture in both groups (see Figure 1). We found a non-significant main effect of group, F(1, 28)=.35, p=ns, but significant effects for semantic relation, F(2,56)=31.91, p<.001, and interaction between group and semantic relation, F(2,56)=3.88, p<.03. Mann-Whitney tests were conducted for each semantic relation. Children with ASD produced a lower proportion of utterances containing supplementary semantic relations than TD children, U=40, p<.002. There was no significant difference in the amount of reinforcing gestures, U=97.5, p=ns, or gestures disambiguating semantic relations, U=94, p=ns, produced by children with ASD and TD children.
Our findings showed that delay in gestural production is still found in children with ASD through their middle to late childhood. Compared to their typically developing counterparts, children with ASD gestured less often and used fewer types of gestures, in particular, markers, which carry culture-specific meaning. Gesture impairment also included the failure to integrate speech with gesture: supplementary gestures are absent in children with ASD. The findings extend our understanding of gestural production in school-aged children with ASD during spontaneous interaction. The results can help guide new therapies for gestural production for children with ASD in middle and late childhood.