Diagnostic Utility of Attention Deficit Hyperactivity Disorder (ADHD) by Brain Activity Flow Patterns Analysis Using Evoked Response Potentials

During a 6 week treatment period, adult subjects with ADHD are prescribed, in an open label fashion, once daily doses of osmotic release methylphenidate to a maximum daily dose of 144 mg. Efficacy and tolerability assessments are completed, in addition to EEG and cognitive testing. Healthy adults without ADHD will not receive medication.