In a visual motion test, however, high IQ scorers seemed almost impaired at noticing big motions. And that may be a key to intelligence, suggest the study authors.

Individuals battling major depressive episodes were found to have abnormal visual processing, according to a Finnish study suggesting altered perception involves changes in the cerebral cortex.

Adding a test that leans on this preference for predictable movements could add another diagnostic tool to the autism toolbox, Omori said.