Dear Parents, Our research group is conducting a study on social functioning in typically developing children. In order to participate in this research study your child must: *Be between the ages of 6 to 12 years *Be in good medical health and not have a neuropsychiatric disorder *Be willing to provide a blood sample and complete IQ testing There is no cost to participate and your child will be paid up to $50 for fully completing this study. For more information, or to sign up, please call (650) 736-1235. Background and study rationale: Autism affects 1 in 68 US children, and is one of the most devastating disorders of childhood. It costs the US $126 billion per year. However, we know almost nothing about the basic biology of autism, and we do not yet have any objective biologically-based diagnostic tests or any effective medications to treat the core social impairments of this disorder. Our research group is addressing these important gaps in knowledge, and your typically developing child could play an important role in helping us achieve these goals, because we need control participants to compare to children with autism enrolled in our studies. For general information regarding questions, concerns, or complaints about research, research related injury, or the rights of research participants, please write to the Administrative Panel on Human Subjects in Medical Research, Administrative Panels Office, Stanford University, Stanford, CA 94305-­‐5401.