Transcranial Magnetic Stimulation

What transcranial magnetic stimulation actually is

Transcranial magnetic stimulation, usually shortened to TMS, is a noninvasive brain stimulation treatment. A device with an electromagnetic coil rests against the scalp and delivers brief magnetic pulses to a targeted region of the brain. Those pulses pass painlessly through the skull and cause small electrical currents in the nerve cells underneath, gently nudging their activity.

The form used for treatment is often called repetitive TMS, because the pulses are delivered in repeated patterns over a session. The U.S. Food and Drug Administration has cleared TMS devices for several uses, most notably major depressive disorder that hasn’t responded well to medication, and it’s also cleared for certain cases of obsessive-compulsive disorder and other conditions. A typical course involves short sessions, often around five days a week for several weeks, done in an office while the person is awake and can drive themselves home afterward.

How it works

The brain runs on electrical signals between nerve cells. A changing magnetic field can induce a small electrical current in nearby tissue, and TMS uses that principle to reach the cortex just under the coil. In depression treatment, the coil is usually aimed at a part of the prefrontal cortex thought to be underactive in many people with depression.

By repeatedly stimulating that area, TMS appears to shift activity in the brain networks involved in mood regulation. Researchers think it works partly by encouraging neuroplasticity, the brain’s ability to adjust its connections over time. The person sits in a chair, the machine clicks and taps against the scalp during each pulse train, and short rest periods break up the stimulation. Sessions usually last somewhere in the range of a few minutes to about forty minutes depending on the protocol.

What transcranial magnetic stimulation isn’t

TMS isn’t electroconvulsive therapy. They’re different treatments. ECT uses electrical current to trigger a brief, controlled seizure under general anesthesia, while TMS uses magnetic pulses, doesn’t cause a seizure on purpose, needs no anesthesia, and doesn’t affect memory the way ECT can.

It also isn’t surgery and doesn’t involve implants or cutting. People stay awake and alert throughout. The most common side effects are mild, such as scalp discomfort or headache near the treatment site. A rare but serious risk is a seizure, which is why providers screen for risk factors. TMS isn’t a guaranteed fix, and results vary from person to person.

Related terms you’ll see next

Electroconvulsive therapy is the other brain stimulation treatment people most often compare with TMS. Treatment-resistant depression describes the situation TMS is most often used for.

Why it matters

TMS gives people another route when antidepressants and therapy haven’t been enough. Because it’s noninvasive, doesn’t require anesthesia, and generally has mild side effects, it can be an option for those who can’t tolerate or haven’t benefited from medication. Whether TMS is a good fit is a decision to make with a psychiatrist who can weigh the person’s history, other conditions, and goals.

<blockquote>
  <p><strong>Transcranial Magnetic Stimulation:</strong> Transcranial magnetic stimulation is a noninvasive treatment that uses magnetic pulses to stimulate nerve cells in the brain. It's used mainly for depression that hasn't responded to medication.</p>
  <p>&mdash; <a href="https://shrinktionary.com/terms/transcranial-magnetic-stimulation/">Shrinktionary</a>, a plain-English mental health dictionary, medically reviewed by a board certified psychiatrist.</p>
</blockquote>