Transcranial Magnetic Stimulation: A Different Approach for Mental Disorders

With nearly 8% of American adults (nearly 20 million people) living with depression, data suggests that medication and talk therapy are only effective in treating around two-thirds of depressive patients, underscoring a concerning gap of people left without relief. In clinical terms, this group of people who are unable to find sufficient benefit through medication is deemed “treatment-resistant”, leaving them feeling without answers or help. However, an alternative type of FDA-cleared treatment is on the rise.

Transcranial magnetic stimulation, or “TMS”, is a non-invasive method of brain stimulation that relies on electromagnetic induction using an insulated coil placed over the scalp, focused on an area of the brain thought to play a role in mood regulation. The coil generates brief magnetic pulses, which pass easily and painlessly through the skull and into the brain. The pulses generated are of the same type and strength as those generated by magnetic resonance imaging (MRI) machines. The approach is gaining incredible traction and acceptance as an effective therapy for treatment-resistant depression due to its high efficacy and safety – in addition to patients experiencing no systemic side effects. 

The ongoing innovation surrounding new types of TMS continues to bring hope to millions of individuals living with mental illness, with a growing number of patients speaking out about the promising results, demonstrating an encouraging shift in the mental health industry.

History of TMS and how it works

While the concept of using magnetic pulses to stimulate the human brain and other parts of the body in an attempt to treat diseases can be traced back to more than 100 years ago, the first modern TMS device was introduced in 1985 by Dr. Anthony Barker. His device and studies proved the influence of magnetic stimulation on the motor cortex to alter the brain’s electrical signals with the use of magnetic fields. At present, devices for repetitive electromagnetic induction have been developed such that different parameters, including the ability to increase or decrease the excitability of cortical areas, can be modified to research neurological and psychological conditions.

Traditional TMS uses a figure-eight shaped coil that sends out an electromagnetic field with the ability to safely reach brain structures involved in depression. By influencing these structures, TMS is able to safely regulate their neural activity, thereby facilitating symptom alleviation and contributing to the patient’s well-being.

Emerging TMS technology enables deeper and broader penetration of electromagnetic stimulation, resulting in more neurons being activated in the target brain regions. This helps maintain the field’s effectiveness without needing to increase the intensity to a level that risks causing undesirable side effects. The deeper, broader field also enhances targeting of the correct brain region, eliminating the need for complex neuronavigation equipment.

While the magnetic pulses activated by standard rTMS only reach a depth of 0.27” (0.7cm) beneath the cortex, new TMS technology can reach up to 1.25” (3.2cm) beneath the cortex, which uniquely enables the ability to safely and directly stimulate both deeper and wider ranges of the brain to treat a number of mental health and addiction conditions.

TMS vs traditional treatment methods

A number of antidepressant medications have been FDA-approved to treat major depressive disorder (MDD). Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are usually prescribed as first-line treatments. However, despite their relatively high remission rates, over 40% of patients with MDD remain unresponsive to antidepressants and are considered to be treatment-resistant. ​​Medication can also have hard-to-tolerate side effects, from insomnia to appetite changes, weight gain and sexual dysfunction.

The side effects from medication are mostly related to the systemic nature of antidepressants which enter the bloodstream and affect the whole body – and can prevent patients from sustaining a medication regimen. It’s also common for antidepressants to lose their efficacy over time, sometimes without the patient even knowing that it’s happening. These diminishing clinical benefits with successive medications underscore the pivotal addition that TMS serves in the psychiatric practice, providing an effective approach to mental health disorders that does not require medication, particularly for treatment-resistant individuals.

As a non-invasive form of treatment, TMS can bring about significant and beneficial change in one’s well-being that can be introduced as a standalone treatment or in combination with other forms of therapy, including medication and psychotherapy. Depression is one of the leading causes of disability in the developed world and treatment-resistant depression affects more than 5 million patients a year in the United States.

Second-line treatments in the outpatient arena have a 21% chance of efficacy in achieving remission and fourth-line treatments have a 13% chance of achieving remission. Patients who battle severe depression through multiple unsuccessful medication trials or find the side effects of treatments to be too intolerable to continue the attempts, can greatly benefit from a non-invasive treatment option such as TMS. While no treatment for depression guarantees a permanent cure, the positive effects of a course of TMS treatment have been shown to have significant durability, often a year or more. When relief begins to lessen, follow-up treatments can be conducted.

TMS moving forward

Overall, findings continue to support the efficacy of TMS for treatment-resistant mental disorders. Clinical research continues to expand the use of TMS to new indications, and is allowing practitioners to optimize protocols, including stimulation parameters, treatment targets and TMS delivery schedules. Ongoing research using neuroimaging and electroencephalography (EEG) is laying the foundation for a deeper understanding of treatment-resistant depression and therapeutic mechanisms of TMS.

We will continue to see an evolution of technology as more and more mental diseases will be able to be treated. As more psychiatric practices continue to offer innovative TMS technology, more patient needs will be met through the treatment of MDD, OCD and smoking cessation.

Ultimately, TMS will continue to be a crucial non-invasive pillar as an approach in treating a wide variety of psychiatric, neurological and addictive illnesses.

About the author

Dr. Aron Tendler is the chief medical officer of BrainsWay, developers of Deep Transcranial Magnetic Stimulation (Deep TMS™), the only TMS treatment that is FDA-cleared to treat four indications: depression, anxious depression, OCD and smoking addiction. As CMO, a medical doctor, and a psychiatrist with decades of experience, Dr. Tendler’s research has been published in numerous peer-reviewed journals.