How Neurostimulation Could Transform Mental Health

Mike Lamb
2 days ago
7 min read

Zapping brains with electricity has long been the stuff of horror stories. From Frankenstein and Jack Nicholson in One Flew Over the Cuckoo’s Nest, to the often grim history of early electroshock therapy, the associations have been… less than reassuring.

But today, this idea is being explored as a treatment for depression and anxiety, and even as a way to improve cognition.

Neurostimulation devices, which utilise tiny electrical currents and magnetic pulses to rebalance brain activity, are increasingly being used in clinical settings and even at home.

After decades of experimentation and research, is this technology finally about to become a miracle tool capable of boosting our mental health and intelligence?

Watch my latest explainer video to find out more:

A brief (and bizarre) history of electrifying the brain

The idea of electrifying the brain has a much longer – and stranger – history than you might think.

“The human drive to zap one’s head with electricity goes back at least to antiquity, and was originally satisfied by means of electric fish,” author Elif Batuman writes. The Romans really did place live torpedo rays on their foreheads in the hope that it would cure their headaches. They prescribed the same treatment for gout, paralysis and even so-called “hysteria”.

The electric fish technique was still being employed well into the 18th century when Italian physicist Luigi Galvani declared that all animals, including humans, contained “their own innate electricity.” He believed this was “secreted by the brain and distributed through the body by the nervous system.” His experiments using electricity to get frogs’ legs to twitch caused a sensation and inspired others to push the idea further.

Galvani’s nephew Giovanni Aldini used this insight to create a gruesome public spectacle. Before horrified crowds, he reanimated the corpses of executed criminals with jolts of electricity – shows that are widely believed to have inspired Mary Shelley’s Frankenstein.

Meanwhile, Galvani’s rival, chemist Alessandro Volta, rejected the idea of “animal electricity”. He ultimately failed in his attempts to disprove it, but did happen to invent the battery along the way.

And there was another alternative theory captivating Enlightenment Europe. In the 1770s, German doctor Franz Mesmer drew high society to his Paris salons, where “patients” gathered around vats of “magnetised” water, iron rods in hands, while Mesmer waved theatrically to the sound of music. Attendees – reportedly including Marie Antoinette – swooned, convulsed and swore they were cured of their ills. Mesmer’s “animal magnetism” theory didn’t survive the scrutiny of a Royal Commission, which was established by Louis XVI and included Benjamin Franklin. But Mesmer left two unexpected legacies: he gave us the word “mesmerise”, and the debunking of his methods helped pave the way for modern clinical trials and our understanding of the placebo effect.

Today’s tech explained

Thanks to revolutionary medical advances like electroencephalograms (EEGs) and brain scans, we now know for certain that the brain essentially runs on electricity. Every thought, movement or emotion is the result of electrical signals firing between our 86 billion neurons. If these signals start to misfire, it can cause a whole host of medical conditions – so it makes sense that electricity might also be able to fix the way our brains work.

Person in a chair connects to a brain machine with a pink brain display on a screen. Scientitsts and technicians stand on either side.

The earliest modern attempt was Electroconvulsive Therapy (ECT), introduced in the 1930s. Delivered without anaesthetic in its brutal early days, it worked by blasting the brain with a current to perform a kind of “hard reset”. Nowadays, ECT is much safer and can be highly effective for people with severe depression. But it remains controversial and is a pretty blunt instrument for such a complex organ.

Today, our understanding of how specific brain regions link to particular conditions has paved the way for more precise tools. Instead of swinging a sledgehammer, we can now use something closer to a scalpel.

In the video, we focused on two that are rapidly going mainstream:

Transcranial Direct Current Stimulation (tDCS): Gentle currents, about 400 times weaker than ECT, are passed between electrodes on the scalp. They don’t force neurons to fire, but nudge them toward activity. Early results suggest benefits for depression, anxiety, stroke recovery and chronic pain.
Transcranial Magnetic Stimulation (TMS): Pulsing magnetic fields start or stop neurons firing in targeted brain areas. It’s more powerful and precise than tDCS but requires clinical administration. The US Food and Drug Administration (FDA) has approved it for treatment-resistant depression, OCD, migraines, and smoking cessation.

But that’s just the start. Neurostimulation now comes in a dizzying alphabet soup of acronyms, each with different applications:

Deep Brain Stimulation (DBS): Surgically implanted electrodes, already an established treatment for Parkinson’s disease, OCD and epilepsy.
Vagus Nerve Stimulation (VNS): Implantable devices send electrical pulses to the vagus nerve – the key nerve connecting the heart and the brain. Used for the treatment of epilepsy, stroke recovery and treatment-resistant depression. A non-invasive version – transcranial VNS (or tVNS) – has been approved in the United States for treating cluster headaches and migraines.
Responsive Neurostimulation (RNS): An implanted “neuro-pacemaker” that monitors brain activity in real time and delivers pulses to stop epileptic seizures before they spread.
Cranial Electrotherapy Stimulation (CES): Low-intensity pulsed currents delivered via earclips or to the temple. The FDA has approved CES in the United States where devices are marketed to help with insomnia, anxiety and depression, although the supporting evidence remains mixed.
Transcranial Alternating Current Stimulation (tACS), Transcranial Random Noise Stimulation (tRNS) and Transcranial Focused Ultrasound Stimulation (tFUS): Experimental techniques that use alternating current, random noise and ultrasound waves to fine-tune brain activity, with early studies exploring ADHD and Alzheimer’s.

Together, these technologies represent a shift: from crude shocks that overwhelm the brain, to subtle nudges that aim to guide it. Whether all of them prove effective remains to be seen – but the sheer variety shows just how far the field has come.

Neurostimulation at home

These new forms of neurostimulation have opened the door to treatments that are convenient, low-risk, and relatively affordable. For a few hundred pounds or dollars, you can now choose from a range of devices that promise to give your brain a gentle nudge.

A cartoon wearing a neurostimulation device in a lounge setting, sat in a pink chair inside a room with a window. A vase with yellow leaves sits nearby. Inset shows a pink house drawing.

One of the market leaders is Swedish company Flow Neuroscience. Their headset uses tDCS to deliver a current about as strong as an AA battery powering a digital clock, targeted at the region of the brain that regulates mood and emotional wellbeing.

In a large clinical trial last year, patients who used the headset for 10 weeks were twice as likely to see their depression go into remission as those using a placebo. In the UK, the NHS began trialling Flow in 2023 and has seen some notable breakthroughs among patients who hadn’t responded to medication alone. The trial has since expanded to include NHS staff struggling with depression.

Flow Neuroscience acknowledges that results can vary. “77% of Flow users experience clinical improvement within three weeks, and in our clinical trial, 57% were completely free of depression after ten weeks,” it says. “This means that Flow works for most people, but since everyone’s brain chemistry and response to treatment are unique, some people may not respond to Flow.”

Another big player in the consumer market is Alpha-Stim, a CES device worn with small ear-clip electrodes that deliver a rhythmic low-level current. It’s marketed for anxiety, insomnia, depression and pain. The evidence, however, is less clear-cut. Some trials have shown promise. But a 2023 study to determine whether it should be made available on the NHS concluded that, while safe, Alpha-Stim was no more effective than a placebo in treating moderate to severe depression.

Can you zap yourself clever?

Beyond mental health, neurostimulation dangles a tantalising prospect: what if it could make us smarter?

The US military certainly thinks it's worth exploring. DARPA – the secretive innovation agency that helped give us the internet, GPS and voice recognition – has been funding neurostimulation research for over a decade.

In one study, pilots who trained with tDCS headsets learned flight exercises dramatically faster. As Andy McKinley, the US military’s principal tDCS researcher, explained to the BBC:

If you imagine learning to ride a bike or a manual vehicle, your process is very conscious at first because you’re thinking about all the steps. But as you do it more often, it becomes more and more unconscious. We wanted to see if we could accelerate that transition with tDCS.

Pilots who received stimulation outperformed their peers by 250% in retests.

Other experiments have found that neurostimulation may boost focus and attention. In one trial, air traffic controllers wearing tDCS headsets were able to maintain unwavering perfect concentration for 40 minutes straight – an endurance feat virtually unheard of under normal conditions.

Outside the military, studies have suggested that neurostimulation can help improve memory, and even the sports world has flirted with it. In 2016, Halo Sport tDCS headsets caused a stir when NBA team the Golden State Warriors started wearing them while training. The device promised to “neuroprime” athletes' brains to deliver “stronger, more synchronous” signals to their muscles. Reputable studies have found some performance gains. But the trend hasn’t caught on – and by 2021 Halo had been acquired by Flow Neuroscience.

The dream of electrically-enhanced learning has been a long time in the making. Over a century ago, Nikola Tesla proposed wiring entire classrooms to bathe pupils in electromagnetic waves, convinced it would make them smarter. The New York schools superintendent even approved a trial, but it never took place. More than 100 years later, Tesla’s electrified classroom of the future has yet to materialise.

Illustration of a brain on a blue background, surrounded by abstract graphs, diagrams, and colorful shapes, conveying a scientific theme.

Electric dreams and future potential

So, might we one day see brain stimulation woven into everyday life – helping us learn faster, focus longer, and perform better? Possibly. The science suggests that gentle stimulation can enhance cognition. But the evidence remains patchy, and beyond small trials (and enthusiastic Reddit hobbyists), neurostimulation for self-optimisation hasn’t quite lived up to the hype… yet.

Where the technology shows the greatest immediate promise is in mental health. More precise, less invasive methods are emerging that could make treatment more accessible, affordable and personalised. For people struggling with conditions like depression and anxiety, where existing treatments haven’t worked, that could be transformative.

As Professor Alex O'Neill-Kerr, one of the NHS doctors involved in trialling tDCS headsets, explains:

If you fail three or four antidepressants, the chances of you responding to treatment is pretty much zero and that represents one third of patients with depression. I've seen patients of mine that I've known for months if not years, get better with transcranial direct-current stimulation.

From Roman soldiers with electric fish to the brutal electroshock therapy of the 20th century, humans have long wondered if a jolt of electricity could be beneficial for the brain. Now, for the first time, science and technology may finally be catching up with the dream.