Atypical development of motion processing trajectories in autism

Recent findings suggest that children with autism may be impaired in the perception of biological motion from moving point-light displays. There have also been reports that some children with autism have abnormally high motion coherence thresholds.
In the current study we tested a group of children with autism and a group of typically developing children aged 5 to 12 years of age on three different motion perception tasks: i) biological motion, ii) motion coherence and iii) form-from-motion, as well as a static perception task iv) contour integration. Our aims were to examine the specificity of any motion perception deficit and to compare the developmental trajectories of the two groups on each of the tasks. The main findings were that children with autism were impaired in the perception of biological motion; sensitivity did not improve with development (i.e. their developmental trajectory was flat). This could not be explained by a perceptual impairment as there were subgroups of children on motion tasks with scores in the normal range who were nevertheless performed atypically on the biological motion task. In contrast, the ability to perceive contours from static Gabor signals develops normally in children with autism.