BEHAVIORAL, INTEGRATIVE AND CLINICAL NEUROSCIENCEAbsence of M100 source asymmetry in autism associated with language functioningSchmidt, Gwenda L.a; Rey, Michael M.a; Oram Cardy, Janis E.b; Roberts, Timothy P.L.a c Author Information aDepartment of Radiology, Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, Pennsylvania, USA bSchool of Communication Sciences and Disorders, University of Western Ontario, London cAutism Research Unit, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada Correspondence to Gwenda L. Schmidt, PhD, Department of Neurology, University of Pennsylvania, 3400 Spruce St. 3W Gates/Chatterjee, Philadelphia, PA 19104, USA Tel: +1 267 825 8330; fax: +1 215 349 8260; e-mail: [email protected] Received 21 April 2009 accepted 12 May 2009 NeuroReport: July 15, 2009 - Volume 20 - Issue 11 - p 1037-1041 doi: 10.1097/WNR.0b013e32832e0ca7 Buy Metrics Abstract Various clinical populations display atypical volume asymmetry of language structures and also the auditory M100 source. Although such atypical volume asymmetries have also been observed in autism, M100 source asymmetries have not yet been investigated. We examined M100 asymmetry in autism and its relationship with language functioning. Evoked neural activity to a 1 kHz tone was recorded using whole-cortex 151-channel magnetoencephalography in three groups of individuals. A single-dipole model identified the M100 generator in auditory cortex in each hemisphere. Healthy adults and control children displayed the expected right-sided M100 anteriority, whereas children with autism showed no such asymmetry. An association was found between language functioning and the degree of asymmetry across the two groups of children, suggesting a possible relationship between functional–structural asymmetry and language ability. © 2009 Lippincott Williams & Wilkins, Inc.