Can brain stimulation reduce how often migraines happen?

For decades, treating migraine has meant waiting for an attack and then reaching for something to stop it. A quieter line of research asks a different question: can we change how the brain behaves so the attacks come less often?

Migraine is a neurological event, not just severe pain

Migraine isn't a headache that happens to feel severe. It's a distinct neurological event, a cascade of brain and nervous-system activity that produces pain alongside a collection of other experiences. During an attack you might have throbbing pain, often on one side, alongside nausea, sensitivity to light, sound, and smell, dizziness, and trouble concentrating. Some people also experience an aura: visual disturbances like flashing lights, zigzag lines, or temporary blind spots that arrive 15 to 60 minutes before the pain begins.

That aura is a clue to where the whole thing starts. It begins in the brain, not in the blood vessels of the scalp. The leading model centers on cortical spreading depression, a slow wave of electrical activity that travels across the surface of the brain at roughly 3 to 5 millimeters a minute (Mungoven et al., 2021). That wave switches on the trigeminovascular system: the network linking the trigeminal nerve, which senses pain in the head and face, to blood vessels and the membranes around the brain. The system releases inflammatory signaling molecules, including calcitonin gene-related peptide (CGRP), and the pain follows (Mungoven et al., 2021).

If migraine starts as an electrical event in the brain, then treatments that act on the brain's electrical behavior aren't a strange idea. They're aimed at the actual source.

Why frequent migraine becomes chronic

Migraine sits on a spectrum. The clinical threshold is 15 or more headache days a month, for more than three months, with at least eight of those days carrying migraine features, above that line is chronic migraine (Headache Classification Committee, 2018). The number doesn't capture what it does to a life: the constant threat of the next attack, the days that can't be planned around, the work and relationships managed around the pain.

Two things about the migraine brain matter here. Between attacks, it's more excitable and more reactive to ordinary stimulation than other brains, so a bright light or a strong smell lands harder. And when attacks happen often, the pain-processing system itself becomes sensitized, amplifying signals it would otherwise damp down (Mungoven et al., 2021). This is central sensitization, and it's a large part of why frequent migraine gets harder to treat over time. The brain learns to expect pain.

The slide from episodic to chronic is real and gradual. Around 2.5% of people with episodic migraine cross into the chronic form each year, usually over months as attacks creep up in frequency (May & Schulte, 2016). People living with chronic migraine report roughly double the disability of those with the episodic form (May & Schulte, 2016). Imaging shows measurable differences in pain pathways and in how sensory regions respond, chronic migraine isn't simply more migraine (Mungoven et al., 2021).

This is where prevention and rescue part ways. Rescue treatment takes each attack as it comes: wait for the pain, then fight it, leaving the underlying tendency toward the next one untouched. But migraine isn't a series of unrelated events. Each attack can deepen the central sensitization that makes the next one easier to trigger, so a pattern left to run tends to entrench itself rather than settle. Prevention works on that pattern instead of on individual experiences: fewer attacks now means less reinforcement of the circuitry driving them, and a better chance of staying on the episodic side of the line.

Why current treatments leave a gap

Today's options fall into two groups. Acute treatments stop an attack in progress: over-the-counter painkillers, prescription triptans, and newer CGRP-blocking drugs. They work for many people, but they don't prevent attacks, and for some people they don't work well, or bring side effects and limits, including the risk that frequent use of acute medication can itself worsen attack frequency over time.

Preventive treatments aim to reduce how often attacks happen: certain blood-pressure medications, anticonvulsants, antidepressants, and botulinum toxin injections. These help some people and not others, and the side-effect profile, weight change, fatigue, cognitive fog, mood effects, means tolerability is often the sticking point. Plenty of people still have frequent, disabling attacks despite working through these options. That unmet need is why researchers keep looking for approaches that are effective, tolerable, and ideally non-pharmaceutical.

How brain stimulation works, and why it might help

The reasoning behind brain stimulation comes directly from what goes wrong in migraine: abnormal cortical excitability and impaired pain control. If you can make a hyperexcitable brain a little less so, and strengthen its own pain-dampening systems, you might stop attacks from starting.

The most studied version is transcranial direct current stimulation (tDCS). Electrodes on the scalp pass a small current, around 1 to 2 milliamps, similar in strength to a 9-volt battery, through the brain (DaSilva et al., 2022). You feel a light tingling or itching under the pads. It isn't painful, and it isn't surgery. The current shifts the resting electrical state of neurons, making them slightly more or less likely to fire depending on the direction of the current, and repeated sessions appear to make that shift last through neuroplasticity, the brain's capacity to rewire with practice (DaSilva et al., 2022).

Three mechanisms are plausible. The current can rebalance cortical excitability, raising the threshold for triggering the spreading-depression wave that starts an attack. It can also strengthen descending pain inhibition: using brain imaging, DaSilva and colleagues at the University of Michigan have shown that motor-cortex stimulation reaches circuits like the periaqueductal gray, a brainstem region that turns down the volume on pain (DaSilva et al., 2022). And by normalizing activity in key pain-processing regions, it may ease some of the central sensitization that builds up in chronic migraine. The mechanism isn't fully mapped, but it lines up with the actual biology of migraine, which is more than can be said for treating the pain only after it has arrived.

What the evidence shows

The most recent pooled review comes from Haghdoost and colleagues (2025), published in Medical Sciences, with a literature search running to May 2025. It gathered the randomized controlled trials comparing brain stimulation with a sham device for preventing episodic migraine in adults: six trials, 172 participants, average age 34, 82% women.

Both electrode placements tested reduced monthly migraine days compared with sham. When the authors removed trials at high risk of bias and re-pooled the rest, the two placements parted ways. Cathodal stimulation over the visual cortex produced a statistically significant drop in headache frequency. Anodal stimulation over the primary motor cortex pointed the same direction but didn't reach significance once the weaker studies were stripped out (Haghdoost et al., 2025). A non-significant result isn't a failure, it means the data can't yet distinguish that placement from sham at this sample size.

An earlier, larger review by Hong and colleagues (2022), pooling 11 trials and 425 patients, found reductions in both how often attacks happened and how intense they were, and reported that stimulation was about as well tolerated as sham, with mild side effects no more common than with a fake device (Hong et al., 2022).

For chronic migraine, the picture is more mixed. Two trials found a benefit: a pilot by De Icco and colleagues (2021) in chronic migraine with medication overuse, and a randomized trial by Hodaj and colleagues (2022) in 36 patients with treatment-resistant chronic migraine. A third, larger trial found no difference from sham (Grazzi et al., 2020). The clearest and most consistent signal is in episodic migraine, which is also where prevention does the most good, by stopping attacks before they have a chance to become chronic.

Where this leaves us

Can you stop a migraine before it starts? Sometimes, for some people, to a moderate degree, the evidence suggests you can reduce how often attacks come. That's not a cure, and the trials are small. But for a condition that lives in the brain, an approach that works at the level of the brain is worth taking seriously. It offers something the treat-after-the-fact model doesn't: a shot at fewer attacks, without a daily systemic drug.

This is the thinking behind Samphire's work. Samphire Headband is designed to act on the brain's electrical activity directly, rather than only on hormones or peripheral nerves, because that's where migraine and related conditions begin. The evidence is promising rather than settled, and that's exactly why it needs to be tested properly: in trials large enough and rigorous enough to show what brain stimulation can and can't do.

If you live with frequent migraines, the idea of getting ahead of an attack instead of chasing it is more than wishful thinking. The biology supports it, and so, increasingly, does the evidence. A neurologist or headache specialist can help you weigh whether a brain-based approach fits alongside your current plan.