Positive Affect Facilitates Eye Gaze Following in Preschoolers with Autism
The ability to follow another person’s gaze is a critical component of joint attention. Joint attention difficulties are a defining characteristic of autism spectrum disorder (ASD). Many therapists working with children who have ASD intentionally use a positive affective framework (e.g., smiles) to increase the child’s attention to their face. However, little research to date has specifically investigated whether positive affect increases eye gaze following.
This study sought to investigate the effectiveness of positive affect in increasing eye gaze following. Given that children with ASD have been found to have difficulty processing subtle expressions of emotion (e.g., a small smile), subtle and exaggerated positive affect were examined separately to assess how emotion intensity influences eye gaze following in children with ASD, relative to typically developing (TD) children.
Eye tracking technology was used to capture the eye gaze behavior of 19 preschoolers with ASD and 23 typically developing preschoolers as they observed the eye gaze shifts of actors displaying neutral, subtle positive, or exaggerated positive expressions. The actors first looked into the camera to establish mutual gaze (simulating eye contact), and then shifted their gaze to one of three pictures on the wall next to them. These pictures were coded as target (congruent with the actor’s gaze) or non-target (incongruent with the actor’s gaze; see Figure 1). Participant eye gaze following was assessed in two ways. First, by calculating the proportion of time the child looked at the target picture compared to the rest of the screen (proportion to target analysis); second, by assessing whether the child had the correct first look to the target picture (correct first look analysis).
The proportion to target analysis showed no group differences between TD children and those with ASD, however a main effect of emotion condition was found (F(2,39) = 3.56, p = .038, η2 = .155). Between-condition pairwise comparisons showed a marginally significant difference between the neutral and subtle conditions (p = .072) with higher values in the subtle condition (see Figure 2), such that there was a higher proportion of eye gaze following to the target picture after the actor displayed the subtle positive facial expression, in both groups. Additionally, the correct first look analysis showed a significant group difference in the exaggerated positive emotion condition only (χ2= 7.532, p = .023). The ASD group was more likely to have the correct first look to the target animal when viewing an actor with an exaggerated positive affect (68%) than the TD group (26%).
These results provide empirical support for the use of positive affect to engage a child’s attention in early intervention. They specifically highlight the potential benefit of exaggerated positive affect for children with ASD, though these preliminary findings still require validation in larger samples.