Studies using 31P-magnetic resonance spectroscopy (MRS) reported on abnormalities in frontal lobe metabolism in schizophrenia. The most consistent findings were a reduction in the resonances of phosphomonoesters (PME) and/or increased phosphodiesters (PDE), which are, respectively, the precursors and the metabolites of membrane phospholipids, thus suggesting an accelerated phospholipid metabolism in the disease. Other studies reported increased high-energy phosphates (ATP-adenosine triphosphate and PCr-phosphocreatine) in schizophrenia, reflecting decreased use of energy in the frontal lobe. We investigated 53 schizophrenic patients (DSM-IV) and 35 healthy controls. Eighteen from these patients were drug nai;ve and the remaining 35 were drug-free for an average of 6 months. Phospholipid metabolism and high-energy phosphates were assessed in the left frontal lobe using 31P-MRS. Psychopathological evaluation was done with the Brief Psychiatric Rating Scale (BPRS) and the Negative Symptoms Rating Scale (NSRS). Neuropsychological evaluation was performed with the Wisconsin Card Sorting Test (WCST), Stroop Test and Wechsler Adult Intelligence Scale. Drug-nai;ve patients showed reduced PDE in the left frontal lobe compared to controls and to previously medicated patients (p
