Objective: Children with specific language impairment (SLI) face risks for social difficulties. However, the nature and developmental course of these difficulties remain unclear. Gaze behaviors have been studied by using eye tracking among those with autism spectrum disorders (ASDs). Using this method, we compared the gaze behaviors of children with SLI with those of individuals with ASD and typically developing (TD) children to explore the social perception of children with SLI.
Methods: The eye gazes of 66 children (16 with SLI, 25 with ASD, and 25 TD) were studied while viewing videos of social interactions. Gaze behaviors were summarized with multidimensional scaling, and participants with similar gaze behaviors were represented proximally in a 2-dimensional plane.
Results: The SLI and TD groups each formed a cluster near the center of the multidimensional scaling plane, whereas the ASD group was distributed around the periphery. Frame-by-frame analyses showed that children with SLI and TD children viewed faces in a manner consistent with the story line, but children with ASD devoted less attention to faces and social interactions. During speech scenes, children with SLI were significantly more fixated on the mouth, whereas TD children viewed the eyes and the mouth.
Conclusions: Children with SLI viewed social situations in ways similar to those of TD children but different from those of children with ASD. However, children with SLI concentrated on the speaker's mouth, possibly to compensate for audiovisual processing deficits. Because eyes carry important information, this difference may influence the social development of children with SLI.