Eye-direction detection: A dissociation between geometric and joint attention skills in autism

This study examined differences between children with autism and control children in the ability to follow another person's direction of gaze. In Expt 1, children with autism, Down syndrome and normally developing children were given two tasks. The gaze monitoring task (GMT) measured the child's spontaneous tendency to follow gaze direction in response to another person's change of head and eye movement. The visual perspective taking task (VPT) measured the child's ability to compute and report what the other person was looking at, when instructed to do so. Results showed that the majority of Down syndrome and normal children passed both tasks. In contrast, children with autism failed the GMT. This failure could not have been due to a lack of the relevant geometric skill, as they passed the VPT. This geometric skill was examined further in Expt 2, using a fine discrimination task which tested children's ability to discriminate degrees of change in the orientation of gaze. Children with autism were well within their developmental age level on this task. These results indicate a dissociation between (impaired) spontaneous monitoring and (intact) geometric analysis of gaze-direction