Brain Training: Are We Over-Thinking It?

Credit: Photograph by Travis Rathbone

At this year's Consumer Electronics Show in Las Vegas, the floor space dedicated to fitness gadgetry was larger than ever, with dozens of new activity trackers, heart-rate monitors, smart scales, and the like. But there was one booth that really generated buzz: Halo Neuroscience, where trade show–goers could don a pair of over-the-ear headphones that delivered a barely perceptible electric current. That faint jolt, the company claims, can help improve your performance for nearly any task — and particularly running, jumping, lifting, and other athletic activities.

A painless zap to the brain to help you get fitter is pretty enticing. But while a handful of professional athletes swear by new devices like these, few doctors or researchers will vouch for them. That's the bad news. The good: You don't have to buy a pricey gadget to train your mind to perform better. In fact, you already possess all the technology you need.

To be sure, brain-boosting devices appear to have made incredible tech strides. Notable among them are the aforementioned headset, called Halo Sport ($749), and the Focus Edge (from $158), another over-the-ear headset. The nascent technology the headsets use is transcranial direct-current stimulation (tDCS). Similarly, Thync Relax, a $200 patch (or “stress-relieving wearable," in company parlance), uses something it calls transdermal electrical neurosignaling (TEN), basically sending juice through cranial nerves under the skin at your neck rather than through your scalp. It's set to debut this spring.

The idea behind all these devices is to use small amounts of low-voltage electricity to coax changes in the brain. The result, the companies say, is that you'll be able to fight through fatigue, focus harder, or block distractions that can make you choke midgame. Researchers admit, though, that when the juice starts to flow, they're not entirely sure what's going on. And what they do know sounds a little, well, muddy. “We're pretty confident that tDCS can change the excitability of the brain tissue beneath the electrode," says Michael Fox, director of the Laboratory for Brain Network Imaging and Modulation at Beth Israel Deaconess Medical Center in Boston.

So how does electrical current translate to improved athletic performance? Washington Redskins player Josh Norman will tell you that using Thync boosts his postgame recovery. He puts the patch on his neck and activates an app on his smartphone. With a faint tingling sensation, the device begins generating what Thync calls “vibes," a kind of  Zen-inducing current that helps the notoriously hotheaded cornerback relax after a game. “It takes away all your cares and worries, like a drug," says Norman, who went to the Super Bowl with the Carolina Panthers last year. (Granted, as a Thync spokesman, the star is paid to say this.) A number of professional baseball and basketball franchises reportedly have tried Halo's headset to “prime their brains" before competing. And Focus' developers point to a study that shows professional cyclists using tDCS were able to increase their endurance by 4 percent. However, that research wasn't conducted using the headset the company makes.

The challenge is in proving the efficacy of these therapies: Though the brain is constantly abuzz with electrical activity, there's no obvious scientific explanation for why a weak electric current to the scalp or skin would produce performance benefits. And while Thync says its own study proves that applying electric currents to spinal and facial nerves can help calm the sympathetic nervous system response — a.k.a. fight-or-flight — not all research is created equal. Some of Thync's research for its Relax patch was conducted by experts with ownership in the company. “What's required is independent replication," says Jared Horvath, a cognitive neuroscientist at the University of Melbourne in Australia. Independent replication is a quality-control step that scientific investigation must undergo to be taken seriously.

As for applying electricity to the scalp, Horvath isn't convinced it can even have an effect. “There's no reason why weak electric currents would even get to the brain, seeing as the scalp, the skull, and spinal fluid are all incredible conductors," he says.

When asked to comment, Halo Neuroscience issued a statement from its chief technology officer, biomedical engineer Brett Wingeier, who said, “There is unequivocal evidence from multiple studies that the level of current used in tDCS does produce meaningful effects on brain function."

But according to Horvath, who's been a leader in electric-stimulation research, the uneven quality of tDCS studies in general undercuts the credibility of these new devices. “Eighty percent of studies looking at brain response to tDCS didn't include a control condition," says Horvath. “That's Science 101. That's the shit you learn the first day you go to a lab." To make matters worse, he says, most studies involve only a dozen or fewer subjects. The small number means it's easy for seemingly meaningful effects to crop up randomly.

To try to make sense of this, Horvath carried out a meta-study of more than 400 papers in the field to look for overall trends. His conclusion, published in the journal Brain Stimulation in 2015, was that the evidence did not support tDCS for sports performance. As for the future of electrical stimulation? “People have been selling electricity as a therapy and enhancement tool for thousands of years," he says. And while the acronyms may fade away, he adds, “the nonsense will continue."

There is proven technology to increase athletic prowess — the gray matter in your own head. It's less sexy than an electric gadget, but the evidence for simple mental cues and strategies to strengthen performance has been quietly growing for decades. These techniques deliver on all the same promises as high-tech devices — for free.

Let's start with stress. Scientists have found that the kind of stress relief touted by Thync can be achieved through sports-specific mindfulness training. Neuroscientist Lori Haase-Alasantro, at the University of California, San Diego, found that she was able to help BMX cyclists who continually choked under the pressure of competition by coaching them to pay careful attention to their thoughts and physical sensations. For example, she would ask athletes to breathe through narrow straws — an exercise that can trigger anxiety — while noticing how their bodies responded. Later, when the cyclists were put in a brain scanner and exposed to stress-inducing stimuli, they exhibited less activity in brain regions associated with anxiety. The result? They learned to keep their cool when on the bike and ready to ride down a halfpipe.

Haase-Alasantro's research was so successful that the university has spun it off into a permanent program for athletes called mPEAK. “People have so many stories that they project onto their performance, and that makes it harder than it already is," says program director Pete Kirchmer. “Our practice helps them witness those thoughts from an outside perspective, so they can say, 'This is just a story, and when I think this way, my body contracts and I go into fear.' With that awareness, negative thoughts almost instantly lose power."

As for the kind of enhanced motor-skill learning that Halo touts, mental training can take care of that, too. The technique, motor imagery, couldn't be more basic: You visualize executing a new skill and focus on the specific steps to achieve it. In one French study, researchers asked tennis players to visualize returning 15 serves toward a target painted on the court. Then the players practiced returning 15 real serves. After two months of twice-a-week sessions, the players who used motor imagery had significantly increased their accuracy in returns, while the controls who did their usual training didn't improve at all.

A subsequent study of amateur golfers focusing on putting skills reached the same conclusion: Training with motor imagery delivers greater skill improvement than physical training alone, says Nicole Detling, a mental performance coach who has worked with numerous Olympic athletes. “If you're working on a new skill during practice, and you spend 10 minutes a day outside of practice imagining yourself doing it perfectly," Detling explains, “your brain signals the muscles that will be used for that movement to occur. So it really is programming your muscles for action."

Such imagery is especially useful just after making a mistake. While we typically get angry and frustrated when we miss an easy layup or double-fault a serve, the negative reaction reinforces a mental image of what went wrong, making it more likely to happen again. Instead, Johnson & Johnson Human Performance Institute co-founder Jack Groppel suggests visualizing the play going perfectly. It's a white lie that's necessary to actually make that happen. “You have to clear the computer so you can reboot and start again," he says.

Perhaps the greatest athletic gains of mental training are in endurance, which requires wielding mind over muscle. Since the 1980s, South African physiologist Timothy Noakes has amassed studies showing that the fatigue that forces an athlete (or any of us) to slow down or quit actually has little to do with how much is left in the tank. Rather, it's the brain shutting down the body early — acting like a subconscious limiter to prevent overexertion. Noakes says this fail-safe helped our ancestors survive on the savanna. “We think humans evolved as long-distance runners, running down prey in the heat," he says. “They had to pace themselves, because it would be pointless to be exhausted at the moment they caught the antelope."

Unfortunately, this fail-safe prevents us from unleashing our full potential in competition or a workout. But it's possible to suppress that feeling of exhaustion and override the urge to quit, says Samuele Marcora, an exercise physiologist at the University of Kent in Britain, and the ability can be strengthened just like a muscle. In one study, Marcora asked test subjects to do repetitive mental tasks — say, watching a stream of shapes and clicking on triangles but not circles — for increasingly long periods, day after day. The subjects found the tasks incredibly boring and mentally draining, which also made them physically sluggish. In time, though, not only did they get better at carrying out the mind-numbing tasks, but they also improved their endurance on a stationary bike. “If you repeat what fatigues you in a systematic way," Marcora explains, “you adapt to become more resistant to the mental and physical fatigue that you induce."

In a follow-up experiment, Marcora put this notion to the test, asking subjects to perform a mentally tiring task as they exercised. Those who did improved their endurance nearly three times as much as control subjects. Pushing the limits of mental fatigue, it appears, is just as useful in building endurance as pushing the limits of physical fatigue. In other words, when you're debating a long bike ride or run and your inner voice says, “Ugh, I don't feel like it," that's the perfect time to go.

Of course, these brain-training methods — mindfulness, visualization, training through mental fatigue — take effort. Popping a device on your head doesn't. But even that fact is a kind of  benefit. The results you get from honing the gears between your ears are guaranteed — if you're willing to put in the work.