MEG investigation of the neural substrates underlying visual perception in autism
Massachusetts General Hospital
Basic & Clinical
Sensory perception abnormalities in autism spectrum disorders (ASDs) have been documented for decades. Reports on sensory perception in ASDs have been variable, with some studies finding inferior performance and some finding superior performance in people with ASDs compared to normally developing individuals. While a great deal of data on sensory performance in ASDs has accumulated, the underlying causes for the abnormalities in ASDs remain unknown. Current hypotheses suggest that these perceptual changes are caused by changes in connectivity, or communication between neurons in different regions of the brain. The present study aims to uncover the neural pathways in the cerebral cortex that underlie sensory processing abnormalities in individuals with ASDs. Dr. Kenet and colleagues will test the hypothesis that in ASDs, the short-range connections between cortical neurons that are involved in sensory processing are functionally weaker, or are underconnected. They will focus on the activity of these connections during visual processing, as how these pathways function in normal individuals is relatively well understood. Neural activity in individuals with ASDs will be observed and measured by magnetoencephalography (MEG) while the subjects are engaged in visual tasks. MEG is a noninvasive method of visualizing neural activity which allows researchers to examine the relative strength of the neuronal connections in a specific brain region. Comparing neural activity during visual processing in individuals with ASDs to that of typical individuals may help us to further understand the nature and cause of sensory perception abnormalities in ASDs.