Objective: Transcranial magnetic stimulation (TMS) is a noninvasive and easily tolerated method of altering cortical physiology. The authors evaluate evidence from the last decade supporting a possible role for TMS in the treatment of depression and explore clinical and technical considerations that might bear on treatment success. Method:The authors review English-language controlled studies of nonconvulsive TMS therapy for depression that appeared in the MEDLINE database through early 2002, as well as one study that was in press in 2002 and was published in 2003. In addition, the authors discuss studies that have examined technical, methodological, and clinical treatment parameters of TMS. Results:Most data support an antidepressant effect of high-frequency repetitive TMS administered to the left prefrontal cortex. The absence of psychosis, younger age, and certain brain physiologic markers might predict treatment success. Technical parameters possibly affecting treatment success include intensity and duration of treatment, but these suggestions require systematic testing.Conclusions: TMS shows promise as a novel antidepressant treatment. Systematic and large-scale studies are needed to identify patient populations most likely to benefit and treatment parameters most likely to produce success. In addition to its potential clinical role, TMS promises to provide insights into the pathophysiology of depression through research designs in which the ability of TMS to alter brain activity is coupled with functional neuroimaging. (Am J Psychiatry 2003; 160:835-845)In 1831, Michael Faraday discovered that electrical currents can be converted into magnetic fields and vice versa. His principle of mutual induction is the basis of transcranial magnetic stimulation (TMS). In TMS, a bank of capacitors is rapidly discharged into an electric coil to produce a magnetic field pulse (Figure 1). When the coil is placed near the head of a human or animal, the magnetic field penetrates the brain and induces an electric field in the underlying region of the cerebral cortex (4) (Figure 2). An electrical field of sufficient intensity will depolarize cortical neurons, generating action potentials. These then propagate to exert their biological effects. For example, TMS over the left motor cortex causes action potentials that propagate through the corticospinal tract, causing twitches in contralateral skeletal muscles.This new technology has been used to affect underlying brain tissue at several levels. First, TMS can alter regional activity within the cortex. Positron emission tomography (PET) has revealed changes in cortical metabolism and dose-dependent changes in regional cortical blood flow in response to TMS (5-7). Such changes are also observed at sites distant from the magnetic stimulus, showing that the effects of TMS propagate to other parts of the brain (6, 7). The connections demonstrated in this manner correspond to known neural pathways in nonhuman primates, suggesting that the propagation of TMS effects occurs by means of...

No abstract

ClinicalTrials.gov identifier: NCT00138775.

No abstract

The findings of this large, well-powered study do not support add-on allopurinol as a treatment for acute mania. This study did not test the efficacy of allopurinol as monotherapy.