TMS feels like a rapid tapping or knocking sensation on your scalp, paired with a loud clicking sound from the machine. Most people find it unusual but tolerable, and the sensation becomes less noticeable after the first few sessions as you adjust. Here’s what to expect at each stage of the process.
The Calibration Step
Before your first treatment begins, your provider needs to find the right intensity for your brain. This calibration process is called motor threshold mapping, and it involves placing the magnetic coil against different spots on your head while delivering single pulses at increasing strengths. The goal is to find the lowest intensity that makes your thumb or fingers twitch involuntarily. That twitch tells the technician the magnetic field is reaching your motor cortex, and your treatment intensity is then set relative to that threshold.
This part can feel odd. You’ll feel individual taps on your scalp and then suddenly notice your hand moving on its own. It’s painless but surprising the first time. The whole calibration typically takes a few minutes.
What the Pulses Feel Like
Once treatment starts, the coil delivers rapid bursts of magnetic pulses to a targeted area of your scalp. The sensation comes from two sources: the magnetic field stimulating superficial nerves in your scalp, and the physical vibration of the coil itself pressing against your head. Because the magnetic field loses strength rapidly as it travels inward, the energy hitting the nerves in your scalp is actually stronger than what reaches your brain tissue underneath.
Most people describe the feeling as a woodpecker-like tapping, a flicking sensation, or a series of small electrical snaps against the skin. The sharpness varies. Some people feel it as a dull, repetitive thud, while others experience something more prickly or stinging, particularly at higher intensities. The sensation is strongest during the first session or two. After that, most patients report it fades into the background as the scalp adjusts. Discomfort at the stimulation site affects roughly 3% of patients enough to report it as a notable side effect, and headaches occur in about 7% of cases. Both tend to be mild.
The Sound
TMS machines are loud. Each pulse produces a sharp clicking or popping noise, and during a rapid-pulse treatment, this becomes a fast, repetitive clacking. The FDA requires that both patients and operators wear earplugs rated for at least 30 decibels of noise reduction during every session. Your clinic will provide them. With earplugs in, the sound is muffled but still clearly audible. Some people compare it to a staple gun firing repeatedly. It’s one of the more distinctive parts of the experience.
What You Do During a Session
You sit in a reclined chair, fully awake, with no anesthesia or sedation. The coil is positioned against your head and held in place by an arm or frame. A technician stays in the room the entire time, and you can ask to stop at any point. Standard sessions run once daily, five days a week, for four to six weeks, with a typical course totaling around 36 sessions. Each session lasts anywhere from about 20 to 40 minutes depending on the protocol your provider uses.
You don’t need to hold perfectly still like you would in an MRI, but you do need to keep your head relatively steady under the coil. Most people read, watch something on their phone, or just sit quietly. There’s no recovery period afterward. You can drive yourself home, go back to work, or continue your day as normal.
How Deep TMS Compares
If your provider uses a deep TMS system (sometimes called dTMS), you’ll wear a padded helmet instead of having a figure-8 shaped coil held against your head. The helmet contains a differently shaped coil designed to reach deeper brain structures. The sensation is similar: tapping, clicking, and some scalp discomfort. Head-to-head comparisons show both types have similar tolerability, so one isn’t significantly more or less uncomfortable than the other.
Mild Effects After a Session
Most people walk out feeling completely normal. The most common after-effects are mild scalp tenderness at the spot where the coil sat and a light headache, both of which typically resolve within an hour or two. Less commonly, some people notice brief lightheadedness or minor mood fluctuations right after treatment. These are short-lived. Serious side effects are rare, occurring in about 1.5% of patients in clinical studies of older adults with depression.
The TMS Dip
Roughly 20 to 25% of patients experience what clinicians call the “TMS dip,” a temporary worsening of symptoms that usually shows up after the second or third session. If you’re being treated for depression, this might mean a few days of feeling more anxious, more irritable, or lower in mood than when you started. It typically lasts a few days, and in rare cases up to two weeks.
This isn’t a sign the treatment is failing. It’s thought to reflect the brain adjusting to stimulation, similar to how antidepressant medications can briefly worsen symptoms before they improve. If the dip feels significant, your provider can adjust the coil placement or stimulation intensity to ease it. There’s no formal published research yet quantifying exactly who is most likely to experience it, but clinically it’s well recognized and considered a normal part of the process for those who go through it.
How the Sensation Changes Over Time
The first session is almost always the most intense in terms of physical sensation. Your scalp hasn’t been exposed to this kind of stimulation before, and everything feels sharper and louder than it will later. By the end of the first week, most people describe the tapping as routine, something they barely notice while scrolling their phone or chatting with the technician. The headaches that sometimes follow early sessions also tend to disappear as treatment progresses. If discomfort remains a problem, your provider can lower the intensity slightly or adjust positioning to avoid more sensitive areas of the scalp.