Not all patients respond to depression medication, leading researchers to explore alternative treatments like transcranial magnetic stimulation (TMS). Two recent studies have made progress in enhancing TMS therapy to be more tailored to individual patients.
Unlike electroconvulsive therapy (ECT), another treatment for depression, TMS has shown promise for patients who do not benefit from antidepressants. Researchers from the University of Helsinki and Stanford University focused on improving the precision of TMS by investigating how specific factors influence the brain’s electrical responses during treatment.
They identified an electrophysiological marker that could potentially serve as a biomarker in the future to gauge the effectiveness of TMS therapy and help customize treatment plans for each patient.
Postdoctoral researcher Juha Gogulski highlights the potential of this approach: “Magnetic stimulation can be effective for some patients with treatment-resistant depression. The biomarker we studied could predict who would benefit from TMS and pave the way for personalized treatment in the future.”
Optimizing Treatment for Individuals
The first study delved into cortical excitability and the impact of stimulation coil placement on electrical responses in the prefrontal cortex. By studying healthy subjects, researchers were able to pinpoint how different areas of stimulation and coil angles affected cortical excitability measured via EEG.
Gogulski notes, “Targeting specific regions of the prefrontal cortex had a significant impact on the quality of electrical responses. Individualized optimization of stimulation sites and coil angles could further enhance the effectiveness of TMS.”
The second study focused on the reliability of the electrophysiological marker in the prefrontal cortex, identifying stimulation site as a key factor influencing its accuracy.
Gogulski emphasizes, “Precision in measuring prefrontal cortex excitability is vital for monitoring brain changes during TMS therapy and eventual clinical application of biomarkers.”
Potential Advantages and the Need for Further Research
While some patients benefit from magnetic stimulation for depression, its efficacy varies. Tailoring treatment based on individual factors such as stimulation site and intensity could yield better results.
Gogulski explains, “Fine-tuning treatment elements like stimulation site, pulse frequency, intensity, and session number could enhance outcomes. TMS therapy typically has minimal side effects, like temporary headaches.”
Gogulski underscores the significance of these studies in systematically mapping prefrontal cortex responses and reliability, emphasizing the potential for real-time monitoring of brain responses during therapy to adjust stimulation as needed.
He concludes, “The findings from these studies will inform the development of personalized brain stimulation therapies guided by electrical biomarkers. However, additional research is essential before implementing new treatment approaches.”
