Modafinil Augmentation in Chronic Schizophrenia and Schizoaffective Disorder

Inclusion Criteria: * Diagnostic and Statistical Manual-IV diagnosis of schizophrenia (all subtypes), illness duration greater than three years * Auditory and visual acuity adequate to complete cognitive tests * Stable dose of antipsychotics for at least 2 weeks prior to entry * Good physical health determined by complete physical examination, laboratory tests, and EKG * Capacity and willingness to give written informed consent. Exclusion Criteria: * Inability to read or speak English * Documented disease of the central nervous system * History of intellectual impairment pre-dating onset of symptoms of psychosis (e.g. mental retardation) * Clinically significant or unstable cardiovascular, renal, hepatic, gastrointestinal, pulmonary or hematologic conditions; * HIV positive * Patients on antidepressants, including monoamine oxidase inhibitors * Uncontrolled hypertension * Pregnancy * Patients with a current diagnosis of substance dependence * Significant history of violence * History of an eating disorder * Ready for discharge within the following 8 weeks.