Young children with autism spectrum disorder use predictive eye movements in action observation

Abstract

Does a dysfunction in the mirror neuron system (MNS) underlie the social symptoms defining autism spectrum disorder (ASD)? Research suggests that the MNS matches observed actions to motor plans for similar actions, and that these motor plans include directions for predictive eye movements when observing goal-directed actions. Thus, one important question is whether children with ASD use predictive eye movements in action observation. Young children with ASD as well as typically developing children and adults were shown videos in which an actor performed object-directed actions (human agent condition). Children with ASD were also shown control videos showing objects moving by themselves (self-propelled condition). Gaze was measured using a corneal reflection technique. Children with ASD and typically developing individuals used strikingly similar goal-directed eye movements when observing others' actions in the human agent condition. Gaze was reactive in the self-propelled condition, suggesting that prediction is linked to seeing a hand-object interaction. This study does not support the view that ASD is characterized by a global dysfunction in the MNS.

Figure 1.

Static representation from the video shown in the human agent condition. See the electronic supplementary material for areas of interest and time window definitions.

Figure 2.

Graphs show hand (index finger) position of the actor as well as gaze position for the three groups as a function of time (ASD, autism spectrum disorder; TD, typically developing). Data represent mean performance for each group. The stimulus video included three reach-to-grasp actions (goals 1, 3, 5) and three placement actions (goals 2, 4, 6). Gaze performance was strikingly similar across groups, and gaze arrived at the goals before the arrival of the hand. As can be seen (e.g. bottom graph), no group tended to track the moving hand. Pictures to the right show a static representation of the video stimulus (oriented according to each graph). Black line, actor's index finger; gaze: dark blue line, ASD preschoolers; gaze: light blue line, TD preschoolers; gaze: pink line, TD adults.