How TMS Works: A Patient Guide to Magnetic Stimulation Therapy

Transcranial Magnetic Stimulation (TMS) is an FDA-approved, noninvasive treatment for depression and certain anxiety disorders. It uses magnetic pulses to stimulate underactive brain regions involved in mood regulation. For many patients who do not respond to antidepressants, TMS offers a safe and effective alternative with minimal side effects and no need for anesthesia or systemic medication exposure.

This guide explains how TMS works, what a treatment session looks like, and what patients can expect from the full course.

What Is TMS?

TMS is a therapy that uses focused magnetic fields to activate specific areas of the brain that are involved in mood, emotion, and thinking. These magnetic pulses stimulate neurons, helping them fire more normally.

How It Works

• A small coil is placed on the scalp

• The coil delivers rapid magnetic pulses

• These pulses activate brain circuits linked to depression

• Over time, the brain becomes more responsive

TMS does not involve electricity entering the body; instead, the magnet induces gentle electrical activity inside targeted brain regions.

Who Is TMS For?

TMS is commonly recommended for:

• Treatment-resistant depression

• Depression with anxiety

• Patients who have not tolerated antidepressants

• Individuals who prefer a non-medication approach

• Patients seeking a therapy with minimal systemic side effects

It is safe for most adults, including those with complex medication histories.

What Happens During a TMS Session?

1. Initial Mapping

At the first session, the TMS provider identifies the precise area on the scalp that corresponds to mood regulation regions of the brain (usually the left dorsolateral prefrontal cortex).

2. Motor Threshold Testing

The clinician determines how strong the magnetic field needs to be to activate the patient’s neurons safely and effectively.

3. Daily Treatment Sessions

Each session typically lasts 18–20 minutes (depending on the protocol). During treatment:

• You sit comfortably in a chair

• A magnetic coil rests lightly against your scalp

• You feel tapping sensations on the forehead or scalp

• You remain awake and alert

• You can listen to music or rest your eyes

There is no sedation and no recovery downtime.

What Does TMS Feel Like?

Most patients describe:

• A tapping or pulsing sensation

• Mild scalp discomfort during early sessions

• Pressure similar to tapping a pencil on the head

• Gradual reduction in sensation over the first week

Side effects are mild and temporary, typically resolving early in treatment.

How Long Is a Full Course of TMS?

A typical course involves:

• 5 sessions per week

• For 6–8 weeks (30–36 treatments)

• Optional booster sessions in the future if needed

Improvement often begins between weeks 2 and 4, with full benefits emerging in the final weeks.

How Effective Is TMS?

Clinical studies show:

• 60–70% of patients respond

• About 30–40% achieve full remission

• Benefits can last months to years with maintenance

For many patients, TMS works after several antidepressant failures.

Advantages of TMS

• Noninvasive

• No systemic side effects

• No weight gain or sexual side effects

• No cognitive impairment

• Can continue working and driving

• Insurance often covers treatment

It is a strong option for patients seeking a biologic treatment without typical medication burdens.

Risks and Side Effects

TMS is considered very safe. Common, mild effects include:

• Scalp tenderness

• Temporary headache

• Facial muscle twitching

• Light fatigue

Rare risks include seizure (extremely rare, less than 0.01%, mostly in patients with uncontrolled epilepsy).

How TMS Helps Rebuild Mood Circuits

Depression weakens activity in key mood-regulating pathways. TMS gradually strengthens these circuits, improving:

• Emotional resilience

• Cognitive flexibility

• Motivation

• Ability to engage in daily life

Patients often describe “feeling like myself again” by the end of treatment.

The Takeaway

TMS is a powerful, evidence-based treatment for depression that uses magnetic stimulation to activate the brain’s natural mood circuits. It is safe, noninvasive, and effective for many patients who have not found relief through traditional medications. With consistent daily sessions, patients can experience lasting improvements in mood and functioning.