History of TMS Therapy: How Long Has TMS Been Around?

As a condition with a variety of symptoms and causes, depression affects different people in different ways. This also means that health care providers can offer a variety of treatments, to differing degrees of success. Most people have heard about traditional talk therapies, antidepressant medications, or recommended changes in diet, exercise, and other lifestyle habits. But there's another treatment that isn't as well-known: transcranial magnetic stimulation, or TMS. You might be surprised to learn just how much research has gone into TMS over the years. So, what is TMS therapy exactly, and how long has TMS been around?

The Connection: Electricity and the Brain

Physicians have long been intrigued by the effects of electricity on the brain. As far back as 46 A.D., Scribonius Largus, the court physician to the Roman emperor Claudius, compiled a book of medical treatments known as Compositiones. It included a recommendation for applying live electric torpedo fish onto patients' scalps to cure headaches. A thousand years later, the physician Ibn-Sidah prescribed using live electric catfish to treat epilepsy.



In the mid-20th century, scientists began applying electrodes to the brain in electroconvulsive therapy (ECT). While ECT is still used successfully, it requires patients to go under general anesthesia and is reserved for those with severe mental illnesses who have not responded to other therapies. It is understood that nerve cells operate by generating electric signals that trigger muscles, for example, or activate chemicals in the brain. To investigate how these processes work and better develop treatments, researchers sought safer ways to introduce electricity to the body.

How Long Has TMS Been Around

In 1985, Anthony Barker and his colleagues were the first to use a magnetic stimulator to activate the brain. This development took advantage of a basic discovery made by physicist Michael Faraday made back in 1831. Barker's device, placed on a patient's head, generated a magnetic pulse that passed painlessly through the scalp and induced an electric current in the underlying brain tissue. Within a few years, scientists engineered improvements to allow TMS devices to deliver repeated magnetic pulses.

Although the new TMS device was originally meant to be a research tool, Hans Martin Kolbinger and his colleagues published a pilot study in 1995 showing evidence that TMS helped patients with major depressive disorder (MDD). The next year, leading TMS researchers convened to set detailed guidelines on how TMS should be used safely and ethically in laboratory research and clinical settings. With these guidelines in place, scientists expanded tests using TMS, initially involving patients with depression who did not find relief from existing treatments.

In 2007, results were published of a major clinical trial that conducted TMS treatments on 301 patients with MDD who had not benefited from other therapies. It found that TMS was safe and could alleviate symptoms of MDD. By then, more than a decade of studies had shown that TMS therapy produced few and minor side effects. In 2008, the U.S. Food and Drug Administration cleared TMS therapy as an accepted depression treatment.

Since 2008, numerous studies have demonstrated that TMS therapy can provide relief for those whose depression symptoms haven't improved after medications and/or talk therapy. Further, TMS has often provided more relief when used in conjunction with other therapies.

Antidepressant medications, for example, have been shown to help relieve symptoms in 40% to 60% of patients. Some people don't like to take antidepressants, even if they are effective, because they sometimes come with side effects such as insomnia, weight gain, headaches, blurred vision, rashes, high blood pressure, and gastrointestinal and sexual problems. TMS is a non-drug, non-invasive therapy with a long history of producing few side effects. Patients sit in a comfortable chair with a TMS device near their scalp. The magnetic pulses are not painful, but rather feel like a gentle tapping, as they stimulate areas of the brain that are known to regulate moods.

When it comes to just how exactly TMS works, scientists have many theories. TMS may increase electrical activity and/or blood flow to brain regions that may be slowed down because these were lacking. Magnetic fields from TMS may help growing brain cells align into more efficient circuits to convey brain signals. Or, TMS could help trigger the release of chemicals that speed brain signaling.

Because these mechanisms logically could also aid in other brain conditions, researchers have explored using TMS to treat other conditions. In 2018, the FDA approved TMS as a treatment for obsessive-compulsive disorder. What's more, TMS is also being tested and used to help patients with Parkinson's disease, migraines, strokes, head traumas, and multiple sclerosis. Talk with your doctor to see if TMS therapy might be a beneficial option for you.