The effects of repetitive transcranial magnetic stimulation (rTMS), a form of treatment for depression, have been demonstrated for the first time by researchers. The results were released in the American Journal of Psychiatry on May 18, 2022.
rTMS is frequently utilized as a treatment for patients whose depression has not responded to conventional approaches, such as drugs. For about 40% of people with severe depression, antidepressants are regarded to be ineffective.
During a rTMS session, a device containing an electromagnetic coil is applied to the patient’s scalp. The device then emits a painless magnetic pulse that stimulates the dorsolateral prefrontal cortex, a region of the brain that is involved in mood control.
The processes underlying rTMS’s effects on the brain are still not fully understood, despite the fact that it has been demonstrated to be successful.
According to Dr. Fidel Vila-Rodriguez, an assistant professor in the department of psychiatry at the University of British Columbia and a researcher at the Djavad Mowafaghian Centre for Brain Health, “When we first started this research, the question we were asking was very simple: we wanted to know what happens to the brain when rTMS treatment is being delivered” (DMCBH).
Patients received one round of rTMS treatment from Dr. Vila-Rodriguez and his team while they were inside an MRI machine to try to find the answer to this question. The ability of the MRI to quantify brain activity allowed the researchers to monitor changes in the brain in real-time.
The researchers discovered that several additional brain areas were also active when the dorsolateral prefrontal cortex was stimulated. These other areas play diverse roles, from controlling emotional reactions to memory and motor control.
The team next examined whether the active regions were linked to patients reporting fewer depressive symptoms after their therapy was finished with the participants after additional four weeks of rTMS treatment.
According to Dr. Vila-Rodriguez, “We found that brain areas that were engaged during the concurrent rTMS-fMRI were strongly connected to excellent outcomes.”
Dr. Villa Rodriguez believes the results might be used to gauge how effectively a patient is responding to rTMS treatments with the help of this new map of the numerous brain regions that rTMS stimulates.
We may now try to understand whether this pattern can be utilized as a biomarker by proving this concept and identifying the parts of the brain that are stimulated by rTMS, he says.