Nuclear magnetic resonance spectroscopy: new insights into the pathophysiology of mood disorders.

Magnetic Resonance Spectroscopy (MRS) is a novel non-invasive approach for investigation of in vivo brain neurochemistry. In this paper, we review the initial studies conducted in mood disorders. 31P MRS studies have suggested membrane phospholipid and energy metabolism abnormalities in the frontal and temporal lobes of bipolar patients. 1H MRS studies have pointed to increase in choline resonance in the basal ganglia of patients with unipolar and bipolar disorders. Mood disorders are not associated with reductions in N-acetyl-aspartate, unlike schizophrenia and other neuropsychiatric disorders. Both 31P and 1H MRS have begun to be used to investigate the mechanisms of action of ECT. 19F and 7Li MRS offer therapeutically relevant new tools for psychopharmacological investigation, allowing the determination of brain concentrations of psychotropic drugs. Measurement of in vivo brain lithium concentrations may have clinical relevance. While several methodological limitations persist, the noninvasiveness and the unique neurochemical insights provided by MRS offer an excellent opportunity for in vivo investigation of the neurobiology of mood disorders.