In 2021, Craig Gibbons was diagnosed with Lyme disease. His doctor prescribed antibiotics, but the medication failed to eliminate one of his most debilitating symptoms: a long-lasting brain fog that made it difficult for him to concentrate or remember information.

So he opted for a different approach: at-home brain stimulation.

For the past several years, Gibbons had been experimenting with transcranial direct current stimulationor tDCS, which sends weak electrical currents to the brain through electrodes attached to the head.

Brain stimulation comes in many different forms, but they all center around the same idea: sending little zaps to specific parts of the brain to alter their activity. Some of its uses are well established: transcranial magnetic stimulation It is used in hospitals and clinics as a way to treat depression. Another version, deep brain stimulation, involves the surgical implantation of electrodes into the brain and has been used for years to relieve symptoms of Parkinson’s disease.

Gibbons, 32, of New York City, had heard that it could be used to relieve symptoms of brain fog.

“It helped me wake up a bit and get things going,” he said.

Most brain stimulation techniques involve placing electrodes (conductors through which electricity travels) on certain parts of a person’s head. These electrodes send small electrical impulses through the skull to the brain.

Medical uses of brain stimulation They are usually done in hospitals or doctor’s offices. But the use of at-home brain stimulation devices is flourishing among a group of enthusiasts, who say it improves their mental state and gives them an edge, such as on an upcoming test or a project at work. Others credit it as a way to achieve deeper meditative states or mental clarity.

Home gadgets are available online and typically range in cost from $40 to around $500. They are typically no bigger than a TV remote or smartphone; Batteries, caps and head straps, saline solution, and other accessories needed to send the weak pulses of electricity to the brain are sometimes sold separately.

Many of them are marketed with authorization from the Food and Drug Administration, which involves a less rigorous review process than is required for FDA approval.

Despite their growing popularity, many scientists oppose using the devices at home because not much is known about their long-term safety, said Robert Reinhart, a neuroscientist at Boston University.

“We are talking about injecting electricity into someone’s brain. Someone could get hurt,” she said. «We need to better understand what these tools can do, including any unintended consequences they may have.»

Science in its early stages

Anna Wexler, an assistant professor of medical ethics and health policy at the University of Pennsylvania, studies why and how people use brain stimulation at home. She found that people are using the devices to treat mental health disorders or to improve mental performance.

«Depression and anxiety are the top two indicators for people,» Wexler said. «But other reasons people used it was to improve, improve focus, improve memory, things like that.»

At-home brain stimulation began in earnest in the early 2010s, Wexler said, despite pushback from doctors and scientists, who were concerned about safety.

«They weren’t very happy that people were using essentially the same technology that they were doing but doing it at home, so they used similar devices to stimulate their own brains with low levels of electricity at home,» he said.

The science behind why electrical stimulation of the brain appears to help memory and thinking skills is still in its early stages, Wexner noted.

Reinhart led a study, published in August in the journal Nature Neuroscience, that found that applying tiny electrical zaps to the brain seemed to boost memory in a group of older adults for at least a month. The study included 150 people ages 65 to 88 who did not have a diagnosed neurological disorder. The patients were asked to wear a cap with embedded electrodes for 20 minutes on four consecutive days. The type of stimulation was similar to transcranial direct current stimulation, but used a different type of electrical current.

The findings suggested that, in addition to its clinical use, brain stimulation could one day become mainstream, similar to the way people use caffeine to increase alertness, he said.

«You can imagine a potential future where people use stimulation,» Reinhart said. “I think people are overwhelmingly interested in increasing their ability to provide a kind of cutting-edge advantage.”

buzz online

Transcranial direct current stimulation has gained ground online. The r/tDCS subreddit is dedicated to discussing the science, technology, and use of brain stimulation devices. The group has more than 16,000 members.

Phil Doughan, 66, of McLean, Virginia, is among them.

He said he became interested in brain stimulation after listening to a podcast on Radiolab, as well as an audiobook, both on the subject.

In January, he purchased a tDCS device from medical equipment supplier Caputron for around $450, hoping it would improve his meditation practice and help clear brain fog, which he attributed to his age.

“I am not looking to fix anything that I perceive to be broken; I’m looking for improvements in my mind,» Doughan said.

Kathie Kane-Willis, 53, of Michigan, said she has been using a tDCS device she bought online for $250 to help alleviate some of her long-standing Covid symptoms, including brain fog.

Since he bought the device last spring, he said, many of his symptoms have lessened.

“I don’t have as much brain fog,” said Kane-Willis, who wears the device for 20 minutes at least twice a day. “It really calms you down; It’s almost like meditating.»

But whether the at-home devices actually help improve people’s mental performance is up for debate, Reinhart said, noting that public adoption of tDCS is happening faster than scientists are accumulating knowledge about the method.

Wexler said he doesn’t expect brain stimulation to achieve mainstream success until studies conclusively show it provides real benefits.

“The basic question is whether this is really working,” he said. «It could be a placebo, it could not be working at all.»

For Dr. Michael Fox, an associate professor of neurology at Harvard Medical School, it’s no surprise that at-home brain stimulation has gained a fan base.

“The promise of being able to non-invasively put on a cap for 20 minutes a day and change or improve your cognitive function is something that people are excited about,” he said.

Still, he said users should proceed with caution. In a 2016 editorial in the magazine annals of neurologyFox cautioned that at-home brain stimulation carries some risks, some more obvious than others.

Known side effects may include itching, tingling, or small burns. Home use advocates argue that these side effects are minimal and that people should be able to use them at their own risk, he said.

But brain stimulation can have far-reaching effects: It can improve some cognitive abilities at the cost of others, Fox said. And while the electrical shocks are targeted, the stimulation affects more parts of the brain than the user may realize.

fox said that the I’d prefer to be used by persons interested in brain stimulation under medical supervision.

But for those in favor, he said, the argument is that “we routinely alter our brain function with things like caffeine and alcohol. I can buy a cup of coffee off the shelf and I can buy a beer off the shelf. And one argument is, why can’t I buy a brain stimulation device in the market?

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