Right now Adderall is in short supply, which, according to some reports, is making it harder for pharmacists to fill prescriptions, driving up black-market prices on campuses, and perhaps forcing some students to rely on their native brainpower to write essays on religious symbolism in Billy Budd.
But take heart, unjuiced undergrads—there may be a solution on the way, albeit one that sounds dubious, even dangerous, at first. It’s called transcranial direct current stimulation (or tDCS), and it involves running a weak electrical current through your brain. While tDCS has been around for decades, in the last couple of years it’s been getting a lot of attention, thanks to research suggesting that it speeds up learning for certain kinds of tasks.
Here’s an example: In a study published in January, researchers tested subjects to see how well they could detect concealed threats in a series of still images, like a bomb disguised by roadside trash—the sort of deadly surprise a soldier in Afghanistan might encounter (the images were taken from a video simulation, called DARWARS Ambush!, that’s used to train soldiers). The subjects had electrodes placed on their heads through which researchers ran varying levels of low-voltage current.
Those given higher levels of current learned to detect threats faster than those given lower levels of current, and both groups performed better with current than without. When they were tested again, an hour later, minus the current, those who had previously been given higher levels of current still performed better even when they weren’t getting zapped. Throughout the experiments, researchers used fMRI neuroimaging to figure out where to place the electrodes and to determine which areas of the brain were experiencing increased blood flow.
As the researchers point out, being able to recognize threats, particularly in war but in other settings too, is a crucial ability, and tDCS seems to “reduce the time required to learn this skill.” Similar results were obtained in a follow-up, double-blind study.
Exactly how and why hooking your brain up to a battery makes learning easier isn’t entirely understood. It seems that the low-level current stimulates neurons, making them more likely to fire, thereby putting the brain in a state where it’s more likely to form connections. Earlier studies have indicated that tDCS appears to improve working memory, and may help in the treatment of depression and Parkinson’s.
This isn’t electroshock therapy, also known as electroconvulsive therapy, which is sometimes used as a last-ditch treatment for severe depression. During ECT, patients are anesthetized and given doses of current high enough to induce seizures. Unlike tDCS, which promotes memory formation, ECT can cause memory loss.
I first heard about tDCS at a conference last year called Narrative Networks, sponsored by Darpa. From the examples above, you can see why the military might be more than a little interested. In a brief presentation, Michael Weisend of the Mind Research Network, an Albuquerque-based nonprofit dedicated to neuroscience investigation, explained how the use of electrical brain stimulation had the potential to “enhance perception, memory, and cognition, whether in healthy individuals or in patients as a remedy for disorders.” I wrote the words “thinking cap” in my notes.
So should we be plugging ourselves in the way we plug in our laptops? A few people are already trying it. Go to YouTube, and you’ll find some daredevils electrifying their brains, or discussing their plans to do so, like this George Mason student. One Web site promises to sell you a kit so you can make your own, though the amateurish promotional video doesn’t inspire confidence.
I called Weisend recently to see what he thought of people experimenting with tDCS. “In the DIY crowd they don’t have the neuroimaging to start the process and know where to place the electrodes,” he told me. “Their success and their safety are going to be limited.” In the laboratory, subjects go through two or three sessions of tDCS over a week. What happens long term if you do more than that? Nobody knows. And the equipment you order from some random person online may not be as reliable as what’s used in a laboratory.
That said, Weisend believes tDCS can be done safely, and he thinks it might be used to prevent memory loss in the elderly or to help patients recover from traumatic brain injuries. He’s tried tDCS on his own brain hundreds of time and hasn’t suffered any deleterious effects—with the notable exception of a few skin burns that were severe enough to leave scars. “You get attached to your work, I guess,” he says.Return to Top