Transcranial Magnetic Stimulation (TMS) has emerged as one of the best options for treating depression when other treatments have not been effective. TMS is typically offered after more common interventions like therapy and anti-depressants have not helped the depression symptoms.
Written by: Dr. R. Dewayne Book, Chief Medical Officer
From the Doctor’s Desk
As a psychiatrist, I’ve spent most of my career working with people who struggle with depression. I’ve seen firsthand how relentless and debilitating it can be. Depression has many contributing factors-biological, genetic, and lifestyle, among others. Over time, all these factors will interact with each other differently and can mean that someone’s depression looks different and needs a different approach or option.
For example, some people will find that their depression initially responds well to a certain anti-depressant and then find that over time it becomes less effective. When this happens, it can often leave a patient feeling lost and fearful that they don’t have any more options.
One of the most promising advances in recent years is Transcranial Magnetic Stimulation (TMS). It has become a very successful treatment for major depressive disorder.
What is Major Depressive Disorder?
Let’s start with a grounding truth: not all depression is the same—and not all depression responds to medication. In clinical terms, we use the diagnosis “Major Depressive Disorder, severe” when someone experiences a persistent low mood, loss of interest or pleasure in daily life, disrupted sleep, appetite changes, concentration difficulties, feelings of worthlessness, or thoughts of death that last for two weeks or more and significantly impair their ability to function.
Symptoms of Severe Major Depressive Disorder:
- Feeling sad, empty, or hopeless most of the day, almost every day
- Losing interest or enjoyment in activities you used to like
- Noticeable changes in appetite or weight (eating much more or much less than usual)
- Trouble sleeping or sleeping much more than usual
- Feeling unusually restless or, on the other hand, moving and speaking more slowly
- Feeling tired or drained of energy nearly every day
- Feeling worthless, guilty, or like you’ve let others down
- Having trouble focusing, thinking clearly, or making decisions
- Thinking about death or suicide, or feeling like life isn’t worth living
Persistent is the key word here. It’s normal for mood to fluctuate in response to stress, loss, or other major life events. That’s part of being human. But when a low mood—and the other symptoms of depression—remain steady over time, it becomes a strong indicator of major depressive disorder.
When this pattern continues despite trying multiple antidepressants or other well-established interventions, clinicians categorize it as “treatment-resistant depression.”
That’s where TMS comes in. TMS has proven to be an effective intervention for treatment-resistant depression.
What Is TMS and How Does It Work?
TMS is a non-invasive treatment that uses focused magnetic pulses to stimulate underactive brain regions involved in mood regulation—specifically, the left dorsolateral prefrontal cortex (DLPFC). In people with depression, neurons in this area often show reduced activity. By using magnetic fields to “wake up” these neurons, TMS helps re-establish healthier patterns of brain activity.
The machines used for TMS are FDA-approved and delivers these pulses in a highly targeted manner. It’s a little like physical therapy session for your brain—done while you sit comfortably in a chair, awake, and able to return to your day immediately after.
Since it is a very precisely focused magnet, there are no systemic side effects. This is unlike many anti-depressant medications which can cause sexual dysfunction, gastrointestinal changes, weight gain, sleep disturbance.
The Neuroscience Behind TMS
TMS works on the principle of electromagnetic induction. When a magnetic coil is placed on the scalp, it generates a rapidly changing magnetic field that induces an electrical current in the cortical tissue beneath. This electrical current stimulates neurons in the targeted brain area, improving communication within the brain’s mood circuitry.
Studies show that repeated stimulation of the DLPFC leads to downstream effects in deeper brain structures like the anterior cingulate cortex, amygdala, and hippocampus —regions implicated in mood, memory, and emotion regulation. Think of it like jumpstarting a complex network that’s gone offline.
Over the course of a treatment series—usually five sessions a week for six weeks—this stimulation can result in lasting changes in neural connectivity. Most patients report significant relief from symptoms, and many achieve full remission.
Science Behind TMS:
- Based on electromagnetic induction – a magnetic coil on the scalp creates a rapidly changing magnetic field.
- Generates an electrical current in the brain tissue beneath the coil.
- Stimulates neurons in targeted areas, improving communication in the brain’s mood circuitry.
- Affects key brain regions – repeated stimulation of the left dorsolateral prefrontal cortex (DLPFC) impacts deeper structures like the anterior cingulate cortex, amygdala, and hippocampus.
- Enhances mood, memory, and emotion regulation by reactivating under functioning neural networks.
- Creates lasting neural changes – regular sessions (5x/week for 6 weeks) strengthen connectivity.
- Often leads to symptom relief or remission for many patients.
Who Is a Candidate for TMS?
TMS is generally recommended for individuals with Major Depressive Disorder, severe, who have not improved after trying at least two different antidepressant medications at an adequate dose and duration.
Before starting, patients undergo a comprehensive psychiatric evaluation to ensure TMS is safe and appropriate.
However, not everyone is eligible. Certain conditions can increase risks or interfere with the treatment’s safety. Additionally, some are concerned with how much TMS may cost. One of the many reasons you will have a comprehensive psychiatric evaluation prior to starting is to make sure insurance will cover the costs.
TMS Candidate Checklist
A thorough evaluation is necessary to determine if someone is a clinical and medical fit for TMS, but in general the following apply:
Likely candidates for TMS:
- Adults diagnosed with Major Depressive Disorder, severe
- Have not responded to at least two antidepressants at an adequate dose and duration
- Cleared during a comprehensive psychiatric evaluation
Not eligible for TMS if any of the following apply:
- Ferromagnetic metal in or near the head/neck (e.g., aneurysm clips, cochlear implants, bullet fragments)
- History of seizure disorder (unless fully controlled and cleared by a neurologist)
- Arteriovenous malformations (AVMs) or other vascular brain abnormalities without specialist clearance
- Implanted medical devices that could be disrupted by magnetic fields (e.g., pacemakers, deep brain stimulators)
What to Expect During a TMS Session
At your first session, we perform a motor threshold mapping, a painless process that determines the precise location for treatment and magnetic dose required to stimulate your brain safely and effectively. This first visit is a little longer. Each subsequent treatment lasts about 20 minutes.
You’ll sit comfortably in a clinic chair while a technician positions the coil on your scalp. You’ll hear a clicking sound and may feel a tapping sensation. There’s no sedation, no recovery time, and you can drive yourself home afterward. Most people are surprised at how “easy” the experience actually is.
Side effects are usually pretty rare, and generally mild: scalp discomfort, headache, or jaw tension. These typically diminish as treatment progresses.
The Human Side of Healing
One of the most meaningful parts of my job as a doctor is witnessing the dramatic, positive changes in my patients. People arrive at our office carrying years of discouragement—sometimes after trying five, six, or more medications. And yet, with each week of treatment, they begin to sit a little taller, smile more, and talk about future plans.
Every time I see this, I’m reminded why I chose this work: to help people get better and to restore hope for a life full of flourishing.
TMS is not a miracle cure. But for many, it represents hope when other doors have closed—offering the possibility not just of symptom relief, but of renewed engagement in life.
How to Get Started with TMS
Beginning TMS treatment starts with a conversation. The first step is a comprehensive psychiatric evaluation to confirm whether TMS is appropriate for your needs. This usually involves reviewing your mental health history, current symptoms, and past treatment experiences, including any medications you’ve tried. This can help with making sure your insurance will cover TMS.
If you’re a candidate, the care team will explain the process in detail—from how the sessions work to what you can expect in terms of comfort, scheduling, and outcomes. You’ll also have a chance to ask questions and discuss how TMS might fit into your broader treatment plan, which could include therapy, lifestyle changes, or medication.
When TMS, psychiatry, and therapy are coordinated within the same team-like at Advaita Integrative Medicine-it creates a unique advantage: your therapist and medication provider can work together to reinforce and build on the gains made through TMS. This integrated approach not only supports faster improvements but can also help sustain progress long after the treatment series ends.
For many people, taking the first step is the hardest part. Whether you’re feeling uncertain, hopeful, or both, the process is designed to give you clarity and help you make an informed decision about whether TMS is right for you.
From my desk to yours, depression may be relentless, but so are we.
