The investigator's previous studies have made progress in the understanding of abnormalities in the glutamate system and brain connectivity in unmedicated patients with schizophrenia and modulation of these by antipsychotic medication. Two indices of glutamatergic dysfunction have been identified. While antipsychotic medications appear to modulate glutamate, the disturbance in the relationship between metabolites is not restored with treatment. In addition, the investigators found that both structural and functional connectivity abnormalities in unmedicated patients with schizophrenia predict patients' response to treatment.