Magnetic Resonance Spectroscopic and Diffusion Tensor Imaging of Adolescents with Autism Spectrum Disorders

The primary objective of this study is to conduct magnetic resonance spectroscopic (MRS) and imaging (MRI) scans to assess the structural and neurochemical profile of the brain in 20 children and adolescents, 6-17 years old with Autism Spectrum Disorder (ASD). For comparison, MRS and MRI will also be obtained from 10 healthy control subjects, matched to the 20 subjects with ASD in age, sex, dexterity, and IQ. All eligible subjects will be administered a detailed assessment battery consisting of cognitive assessments (neuropsychological battery including subsets of the DANVA2 and the CANTAB) and measures of psychosocial functioning (SAICA and M-FES). The study includes 1-3 visits for the screening period at Massachusetts General Hospital (approximately 4 hours of assessments) and one scanning visit at McLean Hospital (approximately 1.5 hours). The investigators hypothesize that youth with ASD versus controls will exhibit increased glutamate concentrations, reflecting glutamatergic overactivity, and increased Cho concentrations, suggesting neuronal abnormality. Furthermore, the investigators hypothesize that compared to neurotypical controls, the structural integrity of white mater tracts will be disrupted in ASD.