GABA-glutamate Interactions and Psychosis

Inclusion criteria: * Ages of 21-45 years from all ethnic backgrounds. * Male or female. * Written informed consent. Exclusion criteria: * DSM-IV diagnosis for a psychotic, depressive or anxiety disorder. * A history of significant medical/neurological disease such as cardiac, thyroid, renal, hepatic abnormality, seizure disorder. Unstable medical condition based on EKG, vital signs, physical examination and laboratory work-up (CBC with differential, SMA-7, LFTs, TFTs, UA, Utox). * History of abnormal EEG. * History of severe allergies or multiple adverse drug reactions. * Any medication that could interfere with either the safety of the study and/or the outcome measures. * Any other conditions which in the opinion of the investigator would preclude participation in the study. * History of major psychiatric disorder in first degree relatives. * Current substance abuse/dependency determined by urine toxicology. * Treatment with medications with CNS effects. * Treatment with benzodiazepines within one week prior to testing. * Current treatment with medications with psychotropic effects. * Education \< 10th grade. * IQ \< 70, MR. * Non-English speaking.