According to a recent study, transcranial magnetic stimulation (TMS) has been shown to be effective in providing rapid relief to patients with severe depression resistant to conventional treatments. But how does this process work? We explain it below.
TMS: a New Approach to the Treatment of Depression
The study, published in the scientific journal Proceedings of the National Academy of Sciences, was led by Anish Mitra of Stanford University. Mitra’s team discovered that TMS works by reversing the direction of certain abnormal brain signals. “Our initial hypothesis was that TMS could alter the flow of neuronal activity in the brain,” explains Mitra.
To test this theory, Mitra developed a novel mathematical method to analyze functional magnetic resonance imaging (fMRI) images, a key tool for identifying active areas in the brain.
How TMS Alters Brain Activity
This new analysis method employs minimal differences in time between the activation of different brain areas, thus also allowing the determination of the direction of said activity. “It was the ideal test to see if TMS can really alter the way signals flow through the brain,” added Mitra.
The study included 33 patients diagnosed with treatment-resistant depressive disorder. Twenty-three of them received a treatment called Stanford neuromodulation therapy, a variant of TMS that incorporates advanced imaging technologies to guide stimulation.
Brain Signals and Depression
The results of the study revealed an important finding: in a healthy brain, the anterior insula (a region that integrates bodily sensations) sends signals to the anterior cingulate cortex, a region that manages emotions. However, in patients with depression, this flow of signals was reversed. The anterior cingulate cortex sent signals to the anterior insula, and this inversion was more pronounced in cases of more severe depression.
The Future of Depression Treatment with TMS
These findings improve our understanding of depression and the role of brain activity in mood.
After Stanford neuromodulation therapy, neuronal flow returned to normal within a week, coinciding with the improvement of symptoms.
The study offers new avenues for tailoring treatments to each person’s brain patterns.
TMS, combined with advanced neuroimaging, could transform the approach to resistant depression.
