How should we regulate tDCS gadgets that promise to boost your brainpower?

How Should We Regulate Those Brain-Zapping Gadgets That Promise to Boost Your Memory?

How Should We Regulate Those Brain-Zapping Gadgets That Promise to Boost Your Memory?

The citizen’s guide to the future.
Dec. 18 2015 7:56 AM

Dialing Up Your Brainpower

How should we regulate those mind-zapping gadgets that promise to boost your memory?

brain-zapping devices.
Care to regulate this, FDA?

Image by Naeblys/Shutterstock

Want to feel calmer or increase your focus? No need to reach for Xanax or Adderall. With a few hundred dollars, you can buy devices that hook up to your smartphone and send low levels of electrical stimulation to your brain. One company, Thync, claims that its gadget can energize or calm your mood; other companies say their devices can improve attention, working memory, and sociability.

These devices are loosely based on research on transcranial direct current stimulation, or tDCS, a technique that sends low levels of electricity to the brain. Compared to its more famous cousin electroconvulsive therapy, tDCS delivers a small fraction of the current: While ECT causes neurons to fire en masse, effectively causing a seizure, tDCS is thought to work by lowering the neuronal firing threshold, essentially making it “easier” for neurons to fire. Unlike other electric and magnetic stimulation techniques that have been widely dismissed as “pseudoscience,” tDCS has been the subject of more than 1,000 studies published in the literature in the last decade, with research falling into two main categories: studies in clinical populations (that is, examining the effects of tDCS to treat disease) and studies in healthy populations. In clinical populations, research has suggested that tDCS may be effective for a variety of conditions and psychiatric disorders, such as depression and chronic pain. Research has also suggested that tDCS may “enhance cognition” in normal, healthy individuals: Studies claim that tDCS enhances everything from creative problem-solving to the acquisition of motor skills. But as with any new scientific technique, there are reasons to be skeptical: A meta-analysis published earlier this year found no reliable cognitive-enhancement effect across single-session studies of tDCS.


The jury is still out on the science, but that hasn’t stopped direct-to-consumer electrical brain-stimulation devices from proliferating. There are currently a dozen devices available, ranging from high-end products controlled via smartphone to more basic “tDCS device kits” that essentially connect a 9-volt battery to your scalp via two wires. And there is an active do-it-yourself brain-stimulation movement, comprised of individuals who build devices from scratch or repurpose other current-providing devices for use on the head.

Whether or not these devices are effective is actually tangential, because by virtue of being on the market, they present a tricky problem for regulators. Should they be considered medical devices, subject to stringent regulation from the Food and Drug Administration? Or are they “wearable technology” like the Fitbit, subject to more lenient consumer regulation from the Consumer Product Safety Commission?

The question is not merely an administrative one—the answer has enormous stakes, both for the consumer electrical brain-stimulation device market and for the burgeoning neurotechnology industry. If classified as medical devices, companies may have to demonstrate safety and efficacy prior to bringing products to market. Since complying with FDA regulations is a costly endeavor, such a classification would probably wipe out most companies selling “tDCS device kits.” In addition, the regulatory precedents set in this area may have implications for other industries where manufacturers make “cognitive enhancement” claims for their products (such as brain-training games and consumer electroencephalography, or EEG, devices marketed for wellness). If, on the other hand, electrical brain-stimulation devices were to be regulated as consumer devices, the market would remain relatively open.

Essentially it is up to the FDA to make the first move, since the CPSC regulates only those products that are not already regulated by the FDA. The crux of the classification question lies within the definition of a medical device. According to the Food, Drug and Cosmetic Act, a medical device is defined as an “instrument, apparatus, implement” that is “intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, treatment, or prevention of disease.” Note the “intended to” wording. An instrument that treats a disease is not necessarily a medical device—but an instrument that is intended for use in doing so is considered a medical device. The FDA determines “intended use” based on manufacturers’ claims, as represented on labeling and advertising material. So: Any device that claims, in its advertising or labeling (interpreted broadly), to diagnose, treat, or cure a disease or condition is considered a medical device.


With this definition in mind, it is worth examining how direct-to-consumer brain-stimulation device manufacturers have represented their products’ “intentions.” Some manufacturers make explicit disease-related claims, stating that tDCS treats diseases like depression, pain, and migraines. Based on these claims, such products would be considered unapproved (that is, illegal) medical devices, even though the FDA hasn’t yet enforced regulation against them. Other devices, however, refrain from making medical claims, sticking instead to more ambiguous advertising language: “power your mind,” “recharge your brain,” or “increase your brain’s plasticity.”

Do such cognitive-enhancement claims make these products medical devices? Though the wording lacks any mention of specific diseases, the definition of a medical device has a second, less well-known, component: Any instrument that is “intended to affect the structure or function of the body” is considered a medical device. At first glance, then, it seems that devices sending electricity to the brain (or cranial nerves, as one company claims) to affect cognitive function—boosting the brain, improving focus—would be considered medical devices, because they are clearly intended to “affect the structure or function of the body” in some way.

But it’s not that simple. If you think about it, what product isn’t intended to affect the structure or function of the body? As I write this, I’m sitting on a chair intended to affect my posture, wearing boots intended to affect the function of my feet. After work, I’ll run on a treadmill—a device that is certainly intended to affect the structure and function of my body. None of these products are considered medical devices. In our daily lives we encounter many products that meet the structure/function criteria, and the FDA would be overburdened if they all were considered medical devices.

Although the FDA is certainly in a better position than the CPSC to regulate these devices—it oversees similar products, has employees with expertise in studying the effects of brain stimulation, and overall is better funded and more powerful—such regulation may not be the best move. How will the FDA define what sorts of cognitive-enhancement claims count as structure/functions claims? For example, while “improve your attention” may be a cognitive-enhancement claim, what about “boost your memory,” “amp your mind,” or “power up?” We may end up with a cat-and-mouse game of words, wherein the FDA sets specific definitions (either formally or by setting regulatory precedents) and manufacturers attempt to write around them. The situation would be similar to the present one, where uncertainty clouds questions of jurisdiction.


However, if the FDA decides not to regulate these devices as medical devices, then the products would be consumer products regulated by the CPSC. This would avoid murky questions regarding “intended use” and decisions about what sorts of cognitive-enhancement claims count as structure/function claims. The resulting enforcement clarity would allow regulators to make real progress regarding safety standards. Though no serious adverse events have been reported in the more than 10,000 subjects studied to date, tDCS reliably causes headache, skin redness, and tingling. Since the CPSC has the authority to set standards for products that may pose “unreasonable risks of injury,” it could set mandatory or voluntary safety standards for devices.

In some ways, brain-stimulation devices for cognitive enhancement are similar to other products, such as direct-to-consumer genetic-testing kits, that have recently presented the FDA with regulatory quandaries. For example, two years ago the FDA told 23andMe to discontinue marketing its “personal genome service,” which, among other things, provided consumers with assessments of their BRCA-related genetic risk for breast cancer. By commercializing techniques traditionally held behind the closed door of science, both direct-to-consumer brain-stimulation devices and direct-to-consumer genetic-testing kits call into question the border between scientific/medical products and consumer ones.

But the issues surrounding brain-stimulation devices are far more complex than those facing direct-to-consumer genetics, because a test that provides health information to consumers clearly falls under the FDA’s jurisdiction. However, noninvasive brain-stimulation devices for cognitive enhancement—if they indeed provide such an effect—get at a deeper philosophical issue: What, exactly, is the difference between enhancement and treatment? Though philosophers and bioethicists have the luxury of endless pontification, the FDA is tasked with making a real-world decision.

Last month, the FDA held a public workshop on this topic. (I spoke on one of the panels, though I have no financial interests in these products.) Based on the discussion paper released ahead of the workshop, it seems that the agency intends to regulate these devices—it just hasn’t quite figured out how to do so. But although the FDA may have the expertise to regulate these devices, the idiosyncrasies of medical device law—namely, the complications regarding “intended use” claims—may not make this the best option, especially given the recent entrance to the market of devices that make no claims at all and instead bill themselves as “direct current sources.” The situation may require a novel solution—such as collaboration between the FDA and CPSC or the involvement of a third party, such as the National Academy of Medicine—to ensure the construction of a coherent framework that best encompasses devices on the market now and anticipates the complex issues that may arise in the future.

This piece was adapted from a research paper that appeared in the Journal of Law and the Biosciences.

This article is part of Future Tense, a collaboration among Arizona State University, New America, and Slate. Future Tense explores the ways emerging technologies affect society, policy, and culture. To read more, visit the Future Tense blog and the Future Tense home page. You can also follow us on Twitter.