Children with autism see simple movements twice as fast as children of the same age without autism, a new study finds. Researchers at Vanderbilt University and the University of Rochester believe this heightened sensory perception will provide clues to what causes the developmental disorder.

To test the theory that the overwhelming sensory stimulation of autism inhibits other brain functions, researchers studied how autistic children processed moving images, NPR reported.

"One can think of autism as a brain impairment, but another way to view autism is as a condition where the balance between different brain processes is impaired," Duje Tadin, an assistant professor of brain and cognitive sciences and lead author of the study, told NPR. "That imbalance could lead to functional impairments, and it often does, but it can also result in enhancements."

The researchers conducted the study, which will be published in The Journal of Neuroscience, by presenting 20 children with autism and 26 children with typical development, ages 8-17, with short video clips of moving black and white bars. The children were given the task of indicating which direction the bars were heading, left or right.

Every time a participant made the correct direction choice, the next video would be slightly shorter, making it harder to see which direction the bars moved. If a mistake was made, the participant would go back to a video that was a bit longer and easier to see. By doing this, the researchers were able to determine how quickly children with autism can perceive motion, according to Futurity.

What they found was that when the bars in the image had a low contrast, all of the children performed identically. However, when the contrast was increased, all of the kids became better at showing which direction the bars moved.

"But kids with autism got much, much better — performing twice as well as their peers," Jennifer Foss-Feig, a postdoctoral fellow at the Child Study Center at Yale University and co-author of the study, said in a press release.

Autism is a neurodevelopmental disorder characterized by impaired social interactions, communication difficulties, and restricted, repetitive, and stereotyped patterns of behavior. Experts estimate that one 1 out of 88 children at eight-years old has autism, according to the National Institute of Neurological Disorders and Stroke.

This hypersensitivity in autistic children could be both a good and bad thing.

"This dramatically enhanced ability to perceive motion is a hint that the brains of individuals with autism keep responding more and more as intensity increases," Foss-Feig explained in the release. "Although this could be considered advantageous, in most circumstances if the neural response doesn't stop at the right level it could lead to sensory overload."

One researcher, Carissa Cascio, an assistant professor of psychiatry at Vanderbilt University, agreed that there are advantages but also said that "at some point the brain really is over-responding. A strong response to high intensity stimuli in autism could be one reason for withdrawal."


Foss-Feig JE, Tadin DU, Schauder KI, Cascio CA. A Substantial and Unexpected Enhancement of Motion Perception. The Journal of Neuroscience. May 2013; 33.