Children with ASD establish joint attention during free-flowing toy play without face looks.

Children's ability to share attention with another person (i.e., achieve joint attention) is critical for learning about their environments in general and supporting language and object word learning in particular. While joint attention (JA) as it pertains to autism spectrum disorder (ASD) is often more narrowly operationalized as arising from eye gaze or explicit pointing cues alone, recent evidence demonstrates that JA in natural environments can be achieved more broadly through multiple other pathways beyond gaze and gestures. Here, we use dual head-mounted eye tracking to examine pathways into and characteristics of JA episodes during free-flowing parent-child toy play, comparing children with ASD to typically developing (TD) children. Moments of JA were defined objectively as both the child's and parent's gaze directed to the same object at the same time. Consistent with previous work in TD children, we found that both TD and ASD children rarely look at their parent's face in this unstructured free play context. Nevertheless, both groups achieved similarly high rates of JA that far exceeded chance, suggesting the use of alternative pathways into JA. We characterize these alternate pathways, find they occur at similar levels across both groups, and achieve similar ends: namely, for both groups, targets of JA are named more frequently by parents in those moments than non-jointly attended objects. These findings broaden the conceptualization of JA abilities and impairment in ASD and raise questions regarding the mechanistic role of the face-gaze-mediated JA pathway in ASD.