Positron emission tomography has been the dominant method for probing the neurochemistry of psychiatric disorders in living humans. This bias reflects the widely held belief that biogenic amines are central to the pathologic processes responsible for serious mental disorders including schizophrenia and affective disorders. Until recently, magnetic resonance spectroscopy (MRS), another technology for probing brain chemistry, has been a neglected “stepchild” because the concentrations of biogenic amines, their transporters, and receptors are a thousand-fold below the sensitivity of MRS but are readily measured with the highly radioactive positron emission tomography tracers.
Coyle JT, Konopaske G. Glutamatergic Dysfunction in Schizophrenia Evaluated With Magnetic Resonance Spectroscopy. JAMA Psychiatry. 2016;73(7):649-650. doi:10.1001/jamapsychiatry.2016.0575