Janssen Asperger's MRS (Magnetic Resonance Spectroscopy Risperidone Study

This study will be an open-label, 12-week trial of risperidone in subjects with Asperger's Disorder, according to Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) Criteria. The study has two arms, one involving pre- and post-treatment MRS studies, and one without MRS. The MRS arm will study 18-20 subjects ages 6 and above, with a target of 14 completing patients. For both arms, we plan to a enroll at total of 30 patients to achieve completion for 24 patients. The non-MRS arm of the study will include subjects 6-18 years of age, the bulk of which have completed the study as of the writing of this updated revision. Our hypotheses are that treatment of Asperger's patients with a low dose of risperidone will: 1. decrease ratios of N-acetylaspartate (NAA), creatine, phosphocreatine (Cr + PCr), and choline in the prefrontal lobe, and 2. decrease the severity of negative symptoms and overall improve social behavior, and 3. that the two will be correlated. Specific Aims The primary objectives of this trial are to: * Further assess and investigate the utility of risperidone in the treatment Asperger's disorder. * Assess the efficacy of risperidone in normalizing increased frontal lobe metabolites. * Assess the efficacy of risperidone in normalizing symptoms in Asperger's disorder patients using standardized rating scales to assess the impact on negative symptoms and on social interaction. * Determine whether risperidone's effect on clinical improvement of Asperger's disorder, i.e., negative symptoms, is correlated with normalization of frontal lobe metabolites * Accrue safety and tolerability data on risperidone for this population of patients. This information could potentially be used to provide pilot data for a double blind trial