CLINICAL NEUROSCIENCE AND NEUROPATHOLOGYNeuroanatomic correlates of autism and stereotypy in children with Down syndromeCarter, John C.a; Capone, George T.a b; Kaufmann, Walter E.a b cAuthor Information aCenter for Genetic Disorders of Cognition and Behavior, Kennedy Krieger Institute bDepartments of Pediatrics cPathology, Neurology, Psychiatry and Behavioral Sciences, and Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA Correspondence to Walter E. Kaufmann, MD, Center for Genetic Disorders of Cognition and Behavior, Kennedy Krieger Institute, 3901 Greenspring Ave., Baltimore, MD 21211, USA Tel: +1 443 923 7600; fax: +1 443 923 7696; e-mail: firstname.lastname@example.org Received 3 October 2007; accepted 5 November 2007 NeuroReport: April 16th, 2008 - Volume 19 - Issue 6 - p 653-656 doi: 10.1097/WNR.0b013e3282faa8d8 Buy SDC Metrics Abstract We conducted semiautomated, atlas-based analyses of regional brain volume changes on MRIs of children and adolescents with Down syndrome (DS) (N=15), DS with comorbid autism spectrum disorder (ASD) (N=15), and age-matched or sex-matched typically developing controls (N=22). Selective volumetric changes were correlated with neurobehavioral measures to determine their functional significance. DS involved selective reduction of frontal and parietal gray matter volumes, beyond the global microencephaly typically observed in this condition. DS with comorbid ASD involved relative hyperplasia of white matter in the cerebellum and brainstem compared with DS only. Cerebellar white matter volumes were positively correlated with severity of stereotypies, a distinctive feature of ASD in DS. © 2008 Lippincott Williams & Wilkins, Inc.