TDCS has been found to be effective in boosting learning capabilities and treating symptoms of many health disorders. Science Photo Library / Alamy

Editor's note: For more on tDCS, watch Al Jazeera America's "TechKnow" at 7:30 p.m. ET on Saturday, Sept. 27. The class was the most difficult of the fall 2013 semester, and J.D. Leadam had missed all but one lecture. His grandfather’s health had worsened, and he left San Jose State, where he was studying for a degree in business, to return home to Los Angeles to help out. Before he knew it, midterm exams had almost arrived. At this point, Leadam had, for a while, been playing around with transcranial direct-current stimulation, or tDCS, an experimental treatment for all sorts of health issues that, at its most basic, involves running a very weak electric current through the brain. When he first came across tDCS, Leadam was immediately intrigued but thought, “There’s no way I’m gonna put electrodes on my head. It’s just not going to happen.” After extensive research, though, he changed his mind. He looked into buying a device online, but there wasn’t much available — just one extremely expensive machine and then a bare-bones $40 device that didn’t even have a switch. So he dug around online and figured he could build one himself. He bought all the pieces he needed and put it together. He tried it a few times, but didn’t notice much, so he put it aside. But now, with the test looming, he picked it back up. The professor had written a book, and Leadam knew all the information he’d be tested on was written in its pages. “But I’m an auditory learner,” he said, “so I knew it wouldn’t work to just read it.” He strapped on the device, turned it on and read the chapters. “Nothing,” he thought. But when he got to the classroom and put pen to paper, he had a revelation. “I could remember concepts down to the exact paragraphs in the textbook,” Leadam said. “I actually ended up getting an A on the test. I couldn’t believe it.”

A miracle treatment

The author with his DIY tDCS device. Courtesy Elijah Wolfson “We found that tDCS improved [our subjects’] vigilance performance twice as much as caffeine and the effect lasted more than twice as long,” said McKinley. “People with tDCS reported feeling more energetic, less drowsy and less fatigued.” Other military discoveries are even more intriguing. A research team led by Clark found that certain tDCS “montages” — the industry term for how the electrodes are placed — could increase learning capabilities by up to 250 percent. “The effect was huge,” said Clark. A few years later, New Scientist magazine editor Sally Adee wrote about her experience visiting with the tDCS research group at the federal Defense Advanced Research Projects Agency (DARPA), claiming that just one tDCS session turned her into a super sniper. Talking to NPR’s Radiolab in 2014, Adee added that the tDCS session left her feeling like all the “little angry gnomes” that populate her head were finally shut off for hours afterward. It sounded a lot like descriptions of taking amphetamines such as Adderall, but with none of the side effects, and when the NPR show aired, it created a flurry of tDCS newcomers — myself included — seeking access to this miracle treatment. “We found that tDCS improved [our subjects’] vigilance performance twice as much as caffeine and the effect lasted more than twice as long,” said McKinley. “People with tDCS reported feeling more energetic, less drowsy and less fatigued.” Other military discoveries are even more intriguing. A research team led by Clark found that certain tDCS “montages” — the industry term for how the electrodes are placed — could increase learning capabilities by up to 250 percent. “The effect was huge,” said Clark. A few years later, New Scientist magazine editor Sally Adee wrote about her experience visiting with the tDCS research group at the federal Defense Advanced Research Projects Agency (DARPA), claiming that just one tDCS session turned her into a super sniper. Talking to NPR’s Radiolab in 2014, Adee added that the tDCS session left her feeling like all the “little angry gnomes” that populate her head were finally shut off for hours afterward. It sounded a lot like descriptions of taking amphetamines such as Adderall, but with none of the side effects, and when the NPR show aired, it created a flurry of tDCS newcomers — myself included — seeking access to this miracle treatment.

Not ready for prime time

Perhaps the greatest online repository of information about tDCS is the website Reddit. There, I found a growing DIY community of enthusiasts — some 5,000 subscribers to a subreddit devoted to the treatment, ranging from hobbyists posting video demonstrations of how to put together do-it-yourself tDCS devices to entrepreneurs seeking to corner the burgeoning commercial market. A homemade tDCS device can be constructed from parts that will run you about $5 to $10 (assuming you already have a soldering iron, wire strippers and other basics). Of the commercial versions, Foc.us, marketed as a “tDCS headset for gamers,” which costs about $300, is perhaps the most polished device available. With its sleek techy design, it’s clearly intended to appeal to the same early adopters jumping on, for example, Google Glass. Many of those in the DIY community are “neurohackers” seeking a cognitive leg up in the world. They tend to believe that any and all emerging technologies that might enhance psychological capabilities should be tapped, for the betterment of themselves as individuals and the human species as a whole. Neurohackers include those who simply hone their exercise and nutrition regimen for ideal brain development as well as “Grinders,” who design and implant mechanical devices into their own bodies. The tDCS community, by most accounts, falls somewhere in between. Some say these forms of neuroenhancement could fuel the sort of abuse associated with college students’ use of amphetamines as study aids to gain a competitive edge over one another. But many neuroethicists disagree.

Foc.us is perhaps the most polished tDCS device available, but it has been plagued by dysfunction. Foc.us “People who make these objections forget that we have been enhancing ourselves forever,” said Neil Levy, editor of the journal Neuroethics and head of neuroethics at the Florey Institute for Neuroscience and Mental Health in Parkville, Australia. Levy pointed to the relatively recent development of language as “a massive enhancement in our powers of reasoning,” which he said you can convincingly group with brain zapping as a DIY neuroenhancement technique. But there are also safety concerns — and most tDCS researchers try to dissuade people from at-home use. Foc.us, for example, has been plagued by malfunction: small current and voltage spikes have caused a number of users to report skin burns and even loss of consciousness. Recently, ohsnapitsnathan, a user on the tDCS subreddit, published an extensive investigation into the Foc.us device. The investigation concluded that the technology does not meet general safety guidelines in a number of areas and doesn’t behave as it was designed to. The Food and Drug Administration, the agency responsible for monitoring the safety and efficacy of commercial devices, has yet to take action to regulate tDCS sales. In an email to Al Jazeera America, an FDA spokesperson wrote, “As a matter of policy, FDA does not discuss publically potential or open investigations.” (Foc.us did not respond to requests for comment.) Given the lack of any government-approved device, I contacted J.D. Leadam, who, after tDCS helped him pass his midterm exam, built a carbon copy of his first device and put it up for sale on eBay. The device, listed at $35, sold overnight. He built a third and listed this one for $42. It sold in under an hour. Realizing he had something, Leadam tapped his network and put together an advisory board that included a 30-year FDA consultant who makes sure Leadam isn’t making any actionable claims and an electrical engineer who, Leadam said, “was an expert in safety and quality-control standards, which was very high on my priority list.” They refined the product and took it off eBay, branding it “The Brain Stimulator” and creating a website, where it currently sells alongside accessories like electrodes and sponges. In November of 2013, they sold six of the devices. In February of 2014, monthly sales were still in the teens. But by the spring of 2014 “our sales skyrocketed and I couldn’t make them fast enough,” Leadam said. “We had to hire employees to make them in my living room all day.”

Lab to table

But when my Brain Stimulator arrived in the mail, I got cold feet. So I decided to visit Marom Bikson’s biomedical engineering lab at the City College of New York to see how tDCS is done in a lab environment. Bikson is one of the world’s leading tDCS researchers. He’s also the owner of Soterix Medical, which manufactures the only research-lab-grade tDCS device available, and a consultant to another technology company seeking to bring what he said is the first safe consumer-grade device to market. (The company was not ready to be publicly named as of this writing.) Within three minutes, I was sitting in an armchair, and a graduate student was strapping me in. Suddenly, I was sweating. “Don’t worry,” Bikson said as he sat down across from me. “Most tDCS is at baby-aspirin level right now.” As 2 milliamps of electricity ran through my brain, my head started to tingle; the sensation was slightly uncomfortable, and part of me wanted to rip off the electrode pads, but I fought the impulse. As Bikson and I talked, I felt a sense of dissociation, as though I were watching myself interview him from slightly outside my body. When my 20 minutes were up, and the wires removed from my head, I felt like I was coming out from some spiritual experience, like a long meditation — or maybe that was just a placebo. My DIY experience, at the home of a friend who’d agreed to be another guinea pig, was decidedly lower tech — though similarly inconclusive. In Bikson’s lab, we had used medical-grade single-use electrode adhesives; at my friend’s home I’d rely on sponges soaked in a saline solution. With the device on, and 1 milliamps, then 1.5, running through my brain, I felt a tingle similar to the one I felt in the lab, only stronger. We’d decided to try the “accelerated learning” montage that had been developed and tested by DARPA. The best test of the device we could come up with was to play Nintendo Wii Mario Kart while brain zapping for 20 minutes — our performance seemed easily measurable (we would just play the same course, over and over) and a lot less violent. At first I was miserable, my green dinosaur avatar, Yoshi, falling off the track on every hairpin turn and barely finishing the course in 3:30. By the end, though, I was cracking 3:00. Of course, there was no control here, no way to tell whether I was simply learning a new skill, but I was cautiously optimistic. In the weeks that followed, I stuck to it, undertaking 20 minutes of tDCS four to five days a week. I decided to try to teach myself interactive web design, and whenever I’d run the current through my brain, I’d accompany it with 20 minutes on Code Academy, the teach-yourself-to-code megasite. But after a few weeks, the results I was looking for seemed elusive. I was obviously getting better at coding, but there was no way for me to know what role the electricity was playing. And it was still kind of painful. So I quit, and about two months after visiting Bikson’s lab, my tDCS device is gathering dust on a shelf in my office. There’s certainly a chance I gave up too soon, that I bought into the false promise of a magic bullet, when maybe tDCS is really more akin to meditation or yoga or other disciplines that provide immense mental, emotional and physical-health benefits when one fully commits to them. After all, despite their undying belief in the potential of tDCS, Bikson and others doing research in this area seem more than a little exasperated with all the hype their creations have generated.