Toward a Cross-Species Measure of Social Motivation: Social Attention during Object Engagement in Autism and Williams Syndrome
Objectives: Here we have developed a novel method to assess social motivation in children with ASD and WS, by quantifying their social attention while the child plays with a high-value toy, a competing non-social stimulus.
Methods: We analyzed video clips from the free play section of the Autism Diagnostic Observation Schedule (ADOS), a standardized, semi-structured, play-based interview often used to diagnose ASD. Specifically, we focused on brief segments when the child was actively engaged with a high-value object (an interactive musical toy), and coded the frequency and duration of the child's gaze toward the object, the examiner, and the caregiver. Inter-rater reliability was high (ICC > 0.9). Videos were coded for three groups: a typically developing group, a group with ASD, and a group with WS.
Results: In a small pilot sample (n=6 per group), we found that toddlers with ASD spent significantly less time looking at social partners (caregiver and examiner) compared to typically developing children during periods of engagement with the high-value toy (see figure). While typically developing children frequently alternated their gaze between the toy and social partners, children with ASD looked toward the adults much less frequently. Children with WS were more variable in their social attention, with some behaving more like children with ASD and others more like typically developing children. There was no significant difference in duration of play with the high-value toy across groups, suggesting that it was consistently engaging for all children.
Conclusions: We are currently replicating these findings in a larger dataset which includes both high-risk and low-risk typically developing children, as well as additional ASD and WS participants. Our pilot analyses suggest that a brief behavioral measure pitting a high-value toy against the innate draw of social engagement could serve as a rapid, feasible measure of social motivation, with implications for enhanced clinical assessment and behavioral phenotyping for genetic research in ASD and WS.