April 18th, 2006

This week’s New Scientist reports (behind a reasonably low subscription wall) that Eric Wasserman at the National Institute of Neurological Diseases and Stroke (among several other scientists) has demonstrate that a technique called transcranial direct current stimulation (tDCS) — essentially, running a current of 1-2 milliamps between a pair of electrodes taped to the skull — can increase neuronal firing rates and produce observable and slightly durable (in the hours range) improvements in cognitive performance in both healthy volunteers and stroke and dementia patients. The effect can be targeted at any part of the cerebral cortex by moving the electrodes.

The treatment is painless, and in fact only marginally noticeable. The requisite device is cheap, low-tech, and potentially portable, running off a 9V battery. Indeed Wasserman is quoted as claiming that “Anyone with the know-how could go to an electronics store, buy the components, and build one.”

The open — and central — research question is whether the brain builds up a tolerance, so the stimulation stops working. (The researchers claim confidence that the treatment is safe, which is puzzling if they don’t know whether it builds tolerance. Perhaps they merely mean that it’s safe for the small number of applications they’ve tried on each patient so far.)

From a clinical standpoint, this sounds like a potential breakthrough. But the big market for such devices is probably among healthy people who want a cognitive boost, even temporarily. (How much would a wannabe doctor pay to have his Broca’s area stimulated just before taking the MCAT?)

Whether the technology is electricity, magnetism, chemistry, or sensory stimulation, we’re going to learn, sooner rather than later, how to make people smarter, at least temporarily and with respect to some subset of congitive tasks. What’s scary is how unprepared our regulatory mechanisms seem to be to deal with the tricky set of questions involved. (Chemicals are much more tightly regulated than the other technologies, for no especially good reason other than history.)

The hard problems will come up around techniques that give a cognitive boost, but with undesirable side-effects, and in particular long-run health consequences. The competitive pressure to use those techniques among those competing for elite positions will be intense. The massive cheating, arbitrary rules, and moralistic posturing around “sports doping” doesn’t give me much confidence that we’re going to handle this one properly.

9 Responses to “tDCS: a potential mass-market cognitive enhancer?”

  1. Tom Scudder says:

    The obvious way of discouraging it would be to require that every such device come with a propeller attached to the top.

  2. Pierce Presley says:

    Mr. Scudder obviously hasn’t learned the lesson from baseball’s steroids scandal: even if it means letting another man inject something into one’s buttocks (keep in mind, sports can be a very homophobic environment), some people will do anything to get ahead. Now if it permanently attached a propeller to the top of the cranium, you might have something; lasting shame usually works better than transient embarrassment.

  3. chippy says:

    What’s scary is how unprepared our regulatory mechanisms seem to be to deal with the tricky set of questions involved.
    Isn’t it better to first see where the problems arise and then regulate?
    It seems unlikely that we would be able to predict in advance exactly which potential problems will come to pass and the relative effect size of each.

  4. Finally, a cure for the heartbreak of stupidity. I’m buyin’ one tomorrow. You guys just keep on ponderin’.
    Um…wait…

  5. Nancy says:

    What does Broca’s area have to do with performance on the MCAT? It is a speech center. You might want to stimulate frontal lobes or memory association areas, but those are all over the brain. Here’s the problem — if we don’t know which areas to stimulate, what good is the technique? Did anyone do a placebo control on this? You might be able to put a rubber band around someone’s head and get the same effect.
    The MCAT depends on acquired knowledge, not smarts. You can make someone smarter but if they are ignorant they still won’t do well on that test. The same goes with life. Until there is a way to pour knowledge into someone’s brain wholesale, what good is slightly faster neural processing (or whatever aptitude consists of)?

  6. Mike Kelley says:

    Maybe they are “perfecting” the technique on the pResident, GWBush — this could explain the voices he claims to hear — a few more volts, Karl — all those years of coke and booze have built up a strong natural immunity to neuron flow…

  7. wcw says:

    Hooey. All timed, multiple-choice tests measure two main things above all else: raw quickness and general test-taking skills. The ‘acquired knowledge’ is essentially ancillary except for the few candidates who just don’t know anything at all.
    As someone blessed with the requisite pair of aptitudes, I have long observed friends and colleagues score worse than I, often much worse, despite similar or greater levels of ‘acquired knowledge’. That is precisely the candidate pool for this or similar cognitive enhancements before tests like the MCAT.

  8. fishbane says:

    I must agree with wcw. I’m one of those perverts who enjoy taking tests - I treat them as puzzles. For non-essay tests, I can usually get a passing grade for any topic, no matter how little I know about the actual topic being tested.

  9. James B. Shearer says:

    We already know how to make people temporarily smarter, amphetamines (and other stimulants) have this effect.