Transcranial magnetic stimulation, known as TMS, may be a safe, effective, and noninvasive option for people who have depression that has not improved with medications. TMS creates a magnetic field to induce a small electric current in a specific part of the brain; the current comes from the magnetic field created by an electromagnetic coil that delivers pulses through the forehead.

This procedure does not require sedation, and it does not cause seizures or a loss of consciousness. Those receiving TMS usually are treated four or five times every week for four to six weeks. Research shows that TMS produces few side effects.

Types of TMS

Repetitive Transcranial Magnetic Stimulation (rTMS)

Repetitive transcranial magnetic stimulation, or rTMS, uses a magnet to activate the brain. It has been used as a treatment for depression, anxiety, and other disorders to target a specific location in the brain, which scientists believe reduces the chance for side effects.

  • Each rTMS session usually lasts 30 to 60 minutes and does not require sedation or anesthesia. An electromagnetic coil held against the forehead is placed near an area of the brain that is thought to be involved in mood regulation; short electromagnetic pulses are administered through the coil. The magnetic pulses cause small electrical currents that stimulate nerve cells in the targeted region of the brain; they are about the same strength as a magnetic resonance imaging (MRI) scan.
  • Scientists do not yet know if rTMS works best as a single treatment or combined with medication, psychotherapy, or both. More research continues to determine its safest and most effective uses.

The procedure is relatively new, so long-term side effects are not known. Studies on the safety of rTMS found that most side effects, such as headaches or scalp discomfort, were mild or moderate, and no one experienced a seizure.

Deep Transcranial Magnetic Stimulation (dTMS)   

Deep transcranial magnetic stimulation (dTMS) is a relatively new method of stimulating larger, deeper brain regions.

  • The procedure uses specialized coils that reach about 4 centimeters beneath the surface of the skull. Called H coils, these are designed to target different brain areas; for example, dTMS using the H1 coil has been approved by the FDA for depression that has not improved with any other type of treatment.
  • During a dTMS session, a person wears a cushioned helmet, which generates brief magnetic fields, similar to those in MRI scans. This is an outpatient procedure that has few side effects, and it does not require anesthesia or result in memory loss. Each daily session of 20 minutes takes place over four to six weeks. People who have this procedure can resume their normal activities immediately afterward.

Find out more:

Brain Stimulation Therapies

Can Magnets Cure Depression?


Updated August 2016