1. fMRI and DTI: Converging lines of evidence support the view that ASDs are disorders of connectivity, in which abnormalities in white matter integrity and reduced coordination of activity across brain regions give rise to core features. Recent results from our group (Guenther; Manoach) have identified white matter anomalies in the speech network of high-functioning verbal adults with ASD, specifically in the pathway between the left supplementary motor area (SMA) and left ventral premotor cortex (vPMC), a pathway involved in the initiation of speech output according to the Directions into Velocities of Articulators (DIVA) model of speech production, a leading model of the neural computations underlying speech. These connectivity abnormalities are revealed in both DTI and functional connectivity analyses collected using fMRI. NOTE: IRB approval for the collection of fMRI/DTI data will be obtained from MGH, where this portion of the study will be carried out. Data analyses will be carried out at MGH and BU.