 Autism is defined as a lifelong pervasive developmental disability, as such, symptom recovery is considered rare. Reports by Lovaas and McEachin, Smith Lovaas and more recently by Cohen, Amerine-Dickens, Smith, Smith Groen et al. and Sutera Pandey et al suggest that intensive behavioral intervention programs during preschool years may result in improvement to the point where some children no longer meet criteria for autism by the time they reach school age. Similarly, there are a large number of anecdotal reports of children with autism who, following intensive biomedical intervention e.g., glutencasein free diets, vitamin supplements, chelation, are indistinguishable from their typically developing peers. The goal of the current research is to characterize the behavioral and biological profiles of children with autism who show significant symptom reduction such that they no longer meet criteria for autism Remitted Autism REM-AUT and to contrast them with a group of children who continue to meet criteria for autism AUT and to typically developing TD group of children. Examining whether neurobiological and neurobehavioral symptoms commonly reported in autism are as frequent and severe in children who have responded to treatment is an important first step in determining what factors may contribute to symptom remission in autism. In addition, understanding how children with remitted autism compare to typically developing children will help us better understand whether symptom improvement is through remediation normalization of function or compensation achieving the same behavioraladaptive outcome but through an alternative process. 