It has been proposed that general abnormalities in structural and functional neuronal connectivity may underlie many of the triad of deficits observed in autism. For example, weak central coherence and abnormal temporal binding may be related to alterations in brain functional and/or structural connectivity. Gamma band oscillatory activity, as measured using EEG and magnetoencephalography (MEG), is thought to play an important role in binding and central coherence. Some experiments have demonstrated that gamma activity is abnormal in people with autism, possibly reflecting a cortical GABA dysfunction. Using a whole-head MEG system, the investigators will study activity within the auditory cortex and estimate patterns of cortical synchronization and desynchronization with high precision in both time and frequency. In order to uncover new endophenotypes for autism and the broader spectrum, the researchers will also study parents of affected individuals. Parents of children with autism will be assessed using MEG measures of gamma-band activity in motor and auditory tasks. Their data will be compared to matched adults with no family history of autism spectrum disorders and to matched adults with autism. MEG measures of gamma power and phase-locking will be measured and associated with their structural underpinnings from magnetic resonance imaging (MRI) data. What this means for people with autism: This project will search for broad patterns of abnormal brain activity in individuals with autism and their family members, which may lead to new ways of diagnosing the disorder.