DSM-IV Axis I or II Diagnosis for for healthy subjects

MEM or amantadine for patients

current substance abuse for all subjects

current recreational drug use for all subjects

history of other significant medical illness (e.g. cancer, diabetes, heart disease, HIV, seizures) for all subjects

open head injury or closed head injury with loss of consciousness \> 1 min for all subjects

hearing or visual impairment for all subjects

pregnancy for all subjects

dementia for all subjects

mental retardation for all subjects

Memantine Effects on Sensorimotor Gating and Neurocognition in Schizophrenia