How the brain changes during depression treatment

Artificial intelligence concept of brain technology

Researchers at the University of British Columbia have mapped what happens in the brain when a person receives depression treatment known as repetitive transcranial magnetic stimulation.

A new study charts how the brain changes throughout depression treatment

Researchers have shown for the first time what happens in the brain during repetitive transcranial magnetic stimulation, a treatment for depression (rTMS). On May 18, 2022, the results were published in the journal American Journal of Psychiatry.

When other strategies, such as medication, fail to help a patient treat depression, repetitive transcranial magnetic stimulation is often used as treatment. Antidepressants are thought to be ineffective for about 40% of people with major depression.

A device with an electromagnetic coil is pressed against a patient’s scalp during a TMS session. A painless magnetic pulse is then delivered by the device, to stimulate neurons in the dorsolateral prefrontal cortex, a part of the brain involved in mood regulation.

Although repetitive transcranial magnetic stimulation has been shown to be effective, the mechanisms underlying its effect on the brain are still not well understood.

Dr. Fidel Villa Rodriguez, Associate Professor of Medicine, says: University of British Columbia Department of Psychiatry and Researcher at the Javad Movgian Center for Brain Health (DMCBH).

To answer this question, Dr. Villa Rodriguez and his team gave patients one round of rTMS while they were inside a magnetic resonance imaging (MRI) scanner. Because an MRI can measure brain activity, the researchers were able to see changes taking place in the brain in real time.

The team found that by stimulating the dorsolateral prefrontal cortex, many other brain regions were activated. These other areas are involved in multiple functions – from managing emotional responses to memory and movement control.

The participants then underwent another four weeks of rTMS treatment and the team evaluated whether the active areas were associated with patients with fewer symptoms of depression when treatment ended.

“We found that brain regions activated during simultaneous rTMS-fMRI were significantly associated with good outcomes,” says Dr. Vila-Rodriguez.

With this new map of how rTMS stimulates different regions of the brain, Dr. Villa Rodriguez hopes the findings can be used to determine a patient’s response to rTMS treatments.

“By demonstrating this principle and identifying which areas of the brain are activated by rTMS, we can now try to understand whether or not this pattern can be used as a biomarker,” he says.

Dr. Vila-Rodriguez is now exploring how rTMS can be used to treat a range of neuropsychiatric disorders. Received funding from the Jawad Moavagian Center for Brain Health[{” attribute=””>Alzheimer’s Disease Research Competition to look at rTMS as a way to enhance memory in patients who are showing early signs of Alzheimer’s disease. He also received a grant from the Canadian Institutes of Health Research (CIHR) to study whether the rTMS brain activation patterns can be detected by changes in heart rate.

Dr. Vila-Rodriguez says this type of research will hopefully encourage more widespread adoption and accessibility of rTMS treatments across the country. Despite being approved by Health Canada 20 years ago, rTMS is still not widely available. In British Columbia, there are some private clinics that offer rTMS, but it is not covered by the provincial health plan.

This research was a collaborative effort across the Centre for Brain Health, including DMCBH researchers Dr. Sophia Frangou, Dr. Rebecca Todd, and Dr. Erin MacMillan, as well as members of the University of British Columbia’s MRI Research Centre including Laura Barlow.

Reference: “Predictive Value of Acute Neuroplastic Response to rTMS in Treatment Outcome in Depression: A Concurrent TMS-fMRI Trial” by Ruiyang Ge, Afifa Humaira, Elizabeth Gregory, Golnoush Alamian, Erin L. MacMillan, Laura Barlow, Rebecca Todd, Sean Nestor, Sophia Frangou, and Fidel Vila-Rodriguez, 18 May 2022, American Journal of Psychiatry.
DOI: 10.1176/appi.ajp.21050541