Will all your friends soon be electric? Will you? The centuries-old technique of transcranial direct-current stimulation is gaining new prominence in the science of human augmentation. From “Spark of Genius,” the new Will Oremus article at Slate:
“Exactly how all of this works is not yet fully clear. But the process appears to make neurons in the stimulated area more malleable, so that new connections form more readily while under the influence of the current. It remains to be seen whether those changes are short-lived or enduring, but at least one study has found positive effects persisting for up to six months. The beauty of it, in theory, is that the electric current doesn’t rewire the brain on its own—it just makes it easier for the brain to rewire itself.
At this point it seems obvious that this is far too good to be true. So what’s the catch?
The catch is that we don’t know what the catch is. And to Peter Reiner, a neuroscientist at University of British Columbia, that’s a biggie. If tDCS can so quickly change the brain in ways that we can easily measure, he says, there’s a good chance it could also change the brain in ways we can’t easily measure—or that researchers so far haven’t tried to measure. Scientists often assume they can target the effects of tDCS by stimulating only the part of the brain relevant to the task that the subject is concentrating on. But most would admit there’s some guesswork involved, since brain topography can vary from one person to the next. And Reiner warns that there’s no guarantee the subject’s mind won’t wander, say, to ‘something horrific that occurred earlier today.’ What if tDCS ends up forging traumatic connections along with useful ones?”