Transcranial magnetic stimulation (TMS) is a non-invasive technique that excites neurons in the brain by magnetic pulses introduced through the scalp. It has generally mild side effects and is well tolerated by patients. Research studies on smaller groups of patients have been inconclusive as to its benefits but the first large-scale, multi-centre, double-blind, sham-controlled study of TMS carried out by researchers at Rush University Medical Centre in the U.S. has found that TMS was twice as effective as a 'sham' procedure. The study's author said "these results indicate that TMS provides a novel and attractive treatment option for patients with major depression who have not responded to conventional antidepressant medications".
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