New findings by Melvyn Goodale from Western University's Brain and Mind Institute, in collaboration with Australian researchers at Swinburne University of Technology and La Trobe University, show that people with high autistic tendencies see the world very differently from those with low autistic tendencies.
In a study published by Royal Society Open Science, the international research team revealed that people who show evidence of autistic traits are more likely to suppress coarse (as opposed to fine) visual information when they move their eyes rapidly from one part of the world to another than those without autistic traits.
As a consequence, people who score highly on measures of autism, even those who are not clinically autistic, are more likely to concentrate on the specific details of a visual scene rather than on the overall picture as they move their eyes around.
"This may help to explain why such individuals often see the trees but miss the forest," explains Swinburne's David Crewther, the study's lead author.
Using sophisticated electroencephalogram (EEG) imaging technology to record electrical activity in the brain, the researchers also showed that the failure to see coarse visual information during rapid eye movements is associated with greater suppression of input along a particular visual pathway, the so-called 'magnocellular' pathway that runs from the eyes deep into the brain.
Crucially, the results of the study may help to explain why autistic individuals focus more on details and often miss 'the big picture.' People with autism could be less aware of the global attributes of things like facial expression as they move their eyes from one part of a scene to another and this could contribute to their problems in social interactions.
"This research contributes to a growing body of evidence suggesting that autism spectrum disorders are associated with deficits in sensory processing," offers Goodale, the Canada Research Chair in Visual Neuroscience.