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The Latest DIY Craze: Brain Hacking

Home experimenters are building rigs to send currents through their heads

4 min read
The Latest DIY Craze: Brain Hacking
The Body Electric: Anthony Lee uses head-mounted pads to stimulate his brain with small amounts of electrical current using a home version of equipment developed by researchers studying cognition.
Photo: David Yellen

Anthony Lee had just begun trying to hack his brain when his girlfriend caught him at it. He was sitting in the living room of his Alabama home with electrodes attached to his head, fiddling with the device he’d built to send a current through his gray matter, when she walked in. “It was that awkward moment when your family walks in on you while you’re doing science,” he says with a laugh.

Lee was an early member of a DIY community that’s sprung up around a technology called transcranial direct current stimulation (tDCS). This noninvasive way to jolt brain cells is being studied in labs and clinics for its potential to reveal how our brains function—and perhaps to augment abilities or treat disorders. Unlike most other brain-tweaking technologies, tDCS doesn’t require expensive equipment; all it takes is a 9-volt battery, some simple circuits, and a couple of electrodes. Consequently, it didn’t take long for so-called biohackers to band together and come up with schematics for devices.

Lee isn’t an engineer, but once he heard about tDCS he decided to build his own rig. He discovered a few websites and a subreddit forum where people were exchanging information, and found techies there who could answer his questions. Once he got his tDCS system working, he made a YouTube video to pass on his knowledge. That was a few years ago, and the community has grown dramatically since then. Now, several commercial tDCS headsets are on the market, raising questions about whether home-brew brain hacking should be made so easy.

03RWBiohackersf2BrentWilliamsDSCN0196Mental Manipulation: Brent Williams uses cranial stimulation when he wants to boost his creativity.Photo: Brent Williams

Many self-experimenters got interested because of research studies that have shown tDCS to have a variety of fascinating effects, depending on electrode location and the amount of stimulation. Faster learning, better math skills, improved memory, more creativity: All these enhancements have been observed in one study or another. Lee’s first plan was to use tDCS to learn German, but when he realized that language-learning would still be a huge time commitment, he shifted his focus and decided to test the technology’s cognitive effects with as much scientific rigor as one amateur could pull off. Granted, that’s not all that much; as the user can usually physically feel when a device is turned on, there’s no easy way to control for the placebo effect.

But now the community is taking a turn from enhancing healthy people to helping the sick. With word of tDCS spreading, more people are trying it to treat disorders such as depression, ADHD, and chronic pain. Lee says he and other pioneers are fielding lots of questions from such patients. “Most of us try to help as much as we can, but we’re not working in a lab doing the real experiments, nor are we psychiatrists,” he says.

Brent Williams, the director of a children’s-education technology program at Kennesaw State University, in Georgia, and an electrical engineer by training, is another pioneer who’s fielding requests. He started his own experiments with tDCS in August 2012 and regularly uses it for a creativity boost; he typically does a 20-minute session of 2 milliamps and says he can feel the effects within 5 minutes. Williams keeps a blog about the technology and how to use it safely, and he says he always advises newbies to do plenty of reading before they start their own experiments. But enthusiastic people don’t always take his advice. “TDCS is becoming more widely known to the general public, so there are more people doing dumb things that they shouldn’t be doing,” he says.

03RWBiohackersf3FocussofaFor Entertainment Purposes: Commercial tDCS rigs, such as this device from, are currently sold in the U.S. without regulatory oversight from the FDA.Photo:

Williams argues, though, that these beginners can’t do much damage to themselves. He says that only minor side effects have been reported in the DIY community, such as skin irritation under the electrodes, flashes of light, and headaches. “It’s relatively risk-free,” he says. ‘’Hundreds of thousands of people have been treated by tDCS, and there’s not one report of someone being injured.”

That confident attitude troubles Marom Bikson, a biomedical engineering professor at the City University of New York who has done extensive research on tDCS technology and who has warned of its misuse. He says that the technology’s excellent safety record is based on lab experiments, which use fault-resistant devices and careful medical protocols.

Bikson says that at-home experimenters shouldn’t assume tDCS is risk-free, especially if they’re using rigs they built themselves. “Anybody who has ever tinkered with something at home knows the first time it doesn’t work, then it does work, then the battery blows out or the IC has a fault. That’s fine if you made an automatic door opener,” he says. “But it’s different if you made something that connects to your head.”

The recent emergence of commercial headsets could give would-be experimenters an alternative to cobbling together their own devices, but such products may not be on the market for long. For example, one buzzed-about company,, advertises a US $250 headset as a tool to boost performance on video games while claiming that its product is not a medical device and so not regulated by the U.S. Food and Drug Administration (FDA). If the FDA disagrees with that assessment, the headset and others will be pulled from the market and subjected to the FDA’s onerous approval process.

In such a situation tDCS would once again be left to the mercies of the DIY community—where, Lee says, it will be in pretty good hands. “I don’t think I would have been able to do the experiments I did, and get the results I did, without the community,” he says. “Now I have a pretty good body of knowledge, and I just want to share it with people who are interested.”

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11 min read
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