Subtype-Specific Alterations of γ-Aminobutyric Acid and Glutamatein Patients With Major Depression

Measurement of cortical gamma-aminobutyric acid (GABA) and glutamate concentrations is possible using proton magnetic resonance spectroscopy. An initial report, using this technique, suggested that occipital cortex GABA concentrations are reduced in patients with major depressive disorder (MDD) relative to healthy comparison subjects.

To replicate the GABA findings in a larger sample of MDD patients, to examine the clinical correlates of the GABA reductions in these subjects, and to examine other critical metabolite levels.