Summary: Yes, it’s possible that TMS can help people with bipolar disorder. Transcranial magnetic stimulation (TMS) is a recent development in a class of mental health therapies called brain stimulation techniques (BSTs) that use various methods to stimulate brain areas associated with emotion, cognition, and behavior.
Key Points:
- Evidence shows transcranial magnetic stimulation (TMS) can help people with treatment-resistant depression and obsessive-compulsive disorder.
- New research suggests TMS may also be helpful for people who have bipolar disorder.
- TMS is a non-invasive technique that works by delivering electromagnetic pulses to specific brain areas.
What Is TMS?
Transcranial magnetic stimulation is a noninvasive technique that employs focused electromagnetic pulses to stimulate certain areas of the brain.
Since these brief pulses repeat several times throughout the course of a TMS session, this service is sometimes also referred to as repetitive transcranial magnetic stimulation, or rTMS.
Anthony Barker, PhD, created the first modern TMS therapy device in 1985 – but it would take more than 20 years of study and improvements before TMS authorized for use in the U.S.
In 2008, the U.S. Food and Drug Administration (FDA) granted initial approval of a TMS device for use in the treatment of depression. Through the years, the FDA has approved several additional TMS devices, including portable and handheld versions. It has also expanded the ways that TMS can be used by healthcare providers.
Today, TMS may be used to treat a variety of physical and mental health conditions, including:
- Major depressive disorder
- Treatment-resistant depression
- Depressive episodes related to bipolar disorder
- Obsessive-compulsive disorder (OCD)
- Migraine headache
- Anxiety with co-occurring depression
The FDA has also approved certain TMS devices for use in cortical mapping procedures and smoking cessation programs.
How Does TMS Work?
Most TMS sessions focus on the brain’s prefrontal cortex, or PFC. This is the area at the front of the brain that is associated with functions such as the following:
- Planning
- Decision-making
- Personality
- Mood
- Controlled social behaviors
- Differentiating between good and bad
- Goal-directed actions
- Predicting future outcomes
- Experiencing guilt and remorse
The prefrontal cortex is divided into two sides, each of which appears to have different responsibilities:
- Researchers have found that the left PFC has more dopamine receptors than the right side has. This may be one reason why the left PFC is more closely aligned with goal-directed behaviors and positive emotions such as motivation and reward.
- The right PFC is involved with the production and dissemination of norepinephrine. This neurotransmitter has been linked to anxiety and other negative emotions.
During a TMS session, electromagnetic pulses penetrate the skull and reach a few centimeters into the brain. These pulses are extremely focused. For example, when the TMS device is placed over the client’s left prefrontal cortex, it stimulates activity in that region of the brain only.
As the targeted brain area is stimulated, this may trigger the activation of the neurotransmitters that are associated with that area. If the client has been experiencing severe symptoms of depression, TMS sessions will likely focus on the left PFC, with the goal of decreasing symptoms and improving mood through the increased release of dopamine and certain other neurotransmitters.
What Happens During a TMS Session?
Here is a quick outline of what happens during a typical TMS session:
- The client sits in a comfortable, reclining chair.
- The professional who is providing the service will place a small coil against the client’s head. This coil will emit a series of brief electromagnetic pulses.
- When the TMS device is activated, it emits a slight clicking noise. For this reason, some clients prefer to wear ear plugs or listen to music through approved earbuds.
- During the session, the client may feel a modest tapping sensation from the coil.
- Some clients meditate during TMS sessions. Others read, listen to music, or watch videos.
- A TMS session usually lasts 30-40 minutes.
Once the session is over, the client should feel no strong lingering aftereffects. Some people feel superficial tingling, while others have reported mild headaches. But TMS does not cause detrimental side effects that would preclude a person from fully engaging in other types of therapy or taking part in other daily activities after a session.
TMS clients usually complete multiple sessions over a period of several weeks. The total number of sessions a client needs, and the frequency with which those sessions are scheduled, will be based on the client’s needs and treatment goals.
The Effectiveness of TMS
The effectiveness of transcranial magnetic stimulation has been studied for several decades. This includes significant research both before and after the technique first received FDA approval.
Most of these studies have focused on TMS’s ability to ease the symptoms of depression. Here are a few highlights from these investigations:
- The authors of a May 2019 study in the journal Cureus wrote, “The clinical efficacy of TMS as an antidepressant has been well established. TMS is an innovative and promising treatment modality.”
- A 2020 post on the Harvard Health blog reported that 50%-60% of people with treatment-resistant depression receive a “clinically meaningful response” via TMS therapy. The same post notes that about 33% of these clients experienced a complete elimination of symptoms.
- In a small study that was published Oct. 29, 2021, by The American Journal of Psychiatry, more than 78% of subjects who received TMS therapy experienced a reduction of depression symptoms.
Can TMS Help People with Bipolar Disorder?
TMS appears to be a promising element of treatment for people with bipolar disorder. At the moment, it’s most commonly used for people with bipolar disorder whose symptoms include depression.
Contrary to what some people mistakenly believe, depressive symptoms aren’t present in every person who has bipolar disorder. The three most common forms of bipolar disorder are bipolar I disorder, bipolar II disorder, and cyclothymic disorder:
Bipolar I:
- People who have bipolar I disorder experience manic episodes. They may also have depressive episodes, but these are not required for a diagnosis of bipolar I disorder.
Bipolar II:
- The criteria for bipolar II disorder include hypomanic episodes and major depressive episodes.
Cyclothymic disorder:
- Manic and depressive symptoms that don’t rise to the level of a manic episode or major depressive episode are characteristic of cyclothymic disorder.
In a 2014 letter in The Journal of Neuropsychiatry and Clinical Neurosciences, a team of doctors from the psychiatry department of Weill-Cornell Medical College suggested that TMS may benefit people who have bipolar disorder by stimulating their left prefrontal cortex and either stimulating or inhibiting their right prefrontal cortex.
A 2017 study in the journal Neuropsychopharmacology explored the effectiveness of deep transcranial magnetic stimulation (dTMS) for people who had treatment-resistant bipolar disorder. This small study involved 50 adults who had major depressive episodes related to either bipolar I disorder or bipolar II disorder. The researchers’ findings included the following:
Impact of dTMS on Depression in Bipolar Disorder
- Subjects who received dTMS showed greater improvement than did those in the control group, as measured on the Hamilton Depression Rating Scale (HDRS-17).
- These improvements were greatest during the first four weeks of the study, when the subjects were receiving either dTMS or sham treatments.
- The improvements decreased over the second four weeks, when the subjects were not receiving treatment. But at the end of the eighth week, the subjects who had received dTMS still scored better on the HDRS-17 scale.
The authors of the 2017 study concluded that “deep TMS is a potentially effective and well-tolerated add-on therapy in resistant bipolar depressed patients receiving adequate pharmacotherapy.” They also noted that decreased improvements during the four-week non-treatment phase of the study suggest that extended dTMS may be needed to help clients maintain their progress.
The information in the 2014 letter and the 2017 study was bolstered by a September 2019 study in the open access journal Brain and Behavior.
This study reported that TMS therapy seems to offer a variety of benefits to people who have bipolar disorder and who have not previously responded to either medication or psychosocial treatment efforts. The authors of the 2019 study on TMS for bipolar disorder noted that the therapy seems to be most effective for reducing symptoms of depression.
Research into the ability of TMS to improve manic symptoms, they wrote, has thus far yielded mixed results. However, they noted that the effect on mania has not been studied as extensively as the effect on depression. However, studies do indicate TMS may be beneficial for people who have been having manic symptoms or episodes.
Learn More About TMS for Bipolar Disorder
Continued research is necessary to better understand the benefits of using TMS to treat bipolar disorder. Previous and current research suggests TMS may be a valuable component of a comprehensive treatment plan for adults whose lives have been affected by treatment-resistant bipolar disorder. To learn more, please read this article on our blog:
Gianna Melendez
Jodie Dahl, CpHT