Cracking the Code of Live Human Social Interactions in Autism: A Review of the Eye-Tracking Literature.

Human social interaction involves a complex, dynamic exchange of verbal and non-verbal information. Over the last decade, eye-tracking technology has afforded unique insight into the way eye gaze information, including both holding gaze and shifting gaze, organizes live human interactions. For example, while playing a social game together, speakers end their turn by directing gaze at the listener, who begins to speak with averted gaze (Ho et al., 2015). These findings reflect how eye gaze can be used to signal important turn-taking transitions in social interactions. Deficits in conversational turn-taking is a core feature of autism spectrum disorders. Individuals on the autism spectrum also have notable difficulties processing eye gaze information (Griffin {&} Scherf, 2020). A central hypothesis in the literature is that the difficulties in processing eye gaze information are foundational to the social communication deficits that make social interactions so challenging for individuals on the autism spectrum. Although eye-tracking technology has been used extensively to assess the way individuals on the spectrum attend to stimuli presented on computer screens (for review see Papagiannopoulou et al., 2014), it has rarely been used to evaluate the critical question regarding whether and how autistic individuals process non-verbal social cues from their partners during live social interactions. Here, we review this emerging literature with a focus on characterizing the experimental paradigms and eye-tracking procedures to understand the scope (and limitations) of research questions and findings. We discuss the theoretical implications of the findings from this review and provide recommendations for future work that will be essential to understand whether and how fundamental difficulties in perceiving and processing information about eye gaze cues interfere with social communication skills in autism.