One of the core defining components of autism is impairment in communication, typically manifested as a delay in speech development. To date, neuroimaging studies have shed limited light on the mechanisms behind delay in speech development in autism. We performed magnetoencephalographic-based auditory language mapping in 2 cases of high-functioning autism. Overall, 2 distinct characteristics were found, such as the use of atypical language pathways and cortical hyperexcitability. These neurophysiological findings parallel those reported in 2 other developmental disorders, developmental dyslexia and Rett syndrome. We discuss common mechanisms that may account for cognitive delays across these developmental disorders.
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