Episodes of depression are frequently associated with significant psychosocial deterioration. Depression is a common psychiatric disorder that presents with depressed mood, loss of interest or pleasure, decreased energy, feelings of guilt or low self-worth, disturbed sleep or appetite, and poor concentration. Moreover, depression often comes with symptoms of anxiety. These problems can become chronic or recurrent and lead to substantial impairments in an individual’s ability to take care of his or her everyday responsibilities.

rTMS therapy uses a computerized, electromagnetic medical device to produce and deliver non-invasive, magnetic stimulation using brief duration, rapidly alternating, or pulsed, magnetic fields to induce electrical currents directed at spatially discrete regions of the cerebral cortex. When pulses of TMS are delivered repetitively, this is called repetitive TMS, or rTMS. These pulses can be delivered at either high (10–20 Hz) or low frequency (less than or equal to 1 Hz) . Most clinical TMS treatments delivered for treating depression are typically given at 10 Hz to 18 Hz . The peak magnetic field strength achieved with each pulse is approximately 1.5 Tesla, right underneath the coil. TMS magnetic fields are focal and brief3. In 2008, the United States Food and Drug Administration (FDA) cleared the first TMS device for therapeutic clinical use in Major Depressive Disorder (MDD).

The course may be somewhat protracted—up to 2 years or longer—in those with the single-episode form. However with effective treatment the total duration of the episode and morbidity in terms loss of work or college hours, disturbed social relations and reduced attention and concentration can be reduced. Effective treatment also prevents progression of mild-moderate depressive episode to severe.