Brain Activity Flow Patterns Analysis Using Evoked Response Potentials in Youth With ADHD, Bipolar Disorder, or Autism Spectrum Disorders: A Preliminary Study

Inclusion Criteria: * Male or female participants between 6 and 17 years of age. * Right handedness. * Fulfills DSM-IV-TR diagnostic criteria for ADHD, bipolar disorder (BPD I, II, or NOS), or ASD (autistic disorder, Asperger's disorder, or PDD-NOS) as established by clinical diagnostic interview and supported by K-SADS-E module for respective diagnoses. * Subjects and their legal representative must have a level of understanding sufficient to communicate intelligently with the investigator and study coordinator, and to cooperate with all tests and examinations required by the protocol. * Subjects and their legal representative must be considered reliable. * Each subject and his/her authorized legal representative must understand the nature of the study. The subject's authorized legal representative must sign an informed consent document and the subject must sign an informed assent document. Exclusion Criteria: * Investigator and his/her immediate family; defined as the investigator's spouse, parent, child, grandparent, or grandchild. * I.Q. \< 85 * History of active seizure disorder (as suggested by EEG suggestive of seizure activity and/or history of seizure in last 1 month) * Pregnant or nursing females. * Subjects with a medical condition that will either jeopardize subject safety or affect the scientific merit of the study, including: * Organic brain disorders * Uncorrected hypothyroidism or hyperthyroidism * Renal or hepatic impairment. * Clinically unstable psychiatric conditions or judged to be at serious suicidal risk * Current diagnosis of schizophrenia * History of substance use (except nicotine or caffeine) within past 3 months or urine drug screen positive for substances of abuse * Significant sensory deficits such as deafness or blindness.