Effects of Brain Stimulation on Cognition, Oscillations and GABA Levels in Schizophrenia

Inclusion Criteria: * Participants must be able to sufficiently speak and understand English so as to be able to understand and complete cognitive tasks. * All subjects must have the ability to give valid informed consent. Inclusion Criteria for Patients with Schizophrenia Only: * Diagnosis of schizophrenia, schizophreniform or schizoaffective disorder * No medication changes in the prior month * No medication changes anticipated in the upcoming month * Stable outpatient or partial hospital status * Normal IQ (\>70; IQ will be measured by administering the Wechsler Abbreviated Scale of * Intelligence (WASI) test) * Must not be currently taking the antipsychotic clozapine Exclusion Criteria: * Pacemakers * Implanted electrical (brain and spinal) stimulators * Implanted defibrillator * Metallic implants * Skin damage or skin conditions such as eczema at the sites where electrodes will be placed * Hair styles hindering the placement of electrodes * Cranial pathologies * Head trauma * Epilepsy * Mental retardation * Any known history of neurological disorders (including epilepsy, amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), stroke, cerebral palsy, any DSM-5 axis I psychiatric disorder (for healthy control subjects), autism) * Uncorrected vision problems that would hinder cognitive testing (this also pertains to subjects with color blindness in tasks where discriminating colored objects/items is necessary for successful performance) * Pregnancy * Substance dependence in the past six months * Substance abuse in the past month