Bioethicists have engaged in endless hand wringing in recent years about whether substances that purportedly allow us to remember and process information more efficiently should be available to everyone, not just kids with ADHD. If you can make your brain work better in some way that doesn't entail poring over a pre-calculus text for hours, why bloody not?

The only problem with this argument is that a true cognitive enhancer is hard to come by—and nothing much is on the horizon. That's why I chuckled last week when I read a paper in Frontiers in Human Neuroscience that pegged as brain booster a chemical consisting of two hydrogens and an oxygen to boot.

"Does having a drink help you think?" began the paper in Frontiers. Researchers at the University of East London and the University of Westminster weren't testing the effects of single malts on mental functioning. What they had discovered was that those who felt thirsty and then imbibed water, after going without overnight, logged better performances on a test of reaction time compared to those who hadn't drunk and were longing for a gulp.

The apparent mechanism of action didn't involve heterodimerization of G protein-coupled receptors or any other elaborate biological machination. Slaking thirst appeared to remove the distractions of parched throats so study participants could concentrate on the task at hand. So what's the big deal? Only 34 participants and the results seem pedestrian and even somewhat equivocal: the study also showed poorer performance on a test of flexibility and abstract thinking for those who were properly hydrated.

Maybe all just a fluke, although one of the study's authors, Caroline J. Edmonds of the University of East London, has reported real effects on cognition from water drinking in other studies. The thing is that this same fuzzy absence of clear-cut results besets the science for other supposed brain enhancers. Ritalin and Adderall, which are billed as helping you to concentrate and think better, are gobbled down avidly by the likes of Wall Street traders. John Harris, a bioethicist at the University of Manchester, has raised the question of whether it might even be unethical to prevent healthy people from juicing up with Ritalin, and a commentary in Nature echoed similar views. But here again the science doesn't seem to be gaining any measure of solidity that favors bringing a 20 mg pick-me-up along with pencils and a calculator to a three-hour final. A study published in June by the National Bureau of Economic Research found that, in a large group of children from Quebec, boys on Ritalin performed more poorly in school and girls experienced more emotional problems. The drug can increase mental focus but it often results in a laser-like attachment to the task at hand, inhibiting the necessary shift in attention to avoid bogging down in a given activity.

All of this doesn't take us very far down the royal road to some ultimate form of self-improvement. So relax and have a sip when the waiter serves the ice water before you order. Maybe it'll hasten your choice between the tomato salad or the shrimp cocktail. Just don't expect what's in the glass—whether Pellegrino, tap or Maker's—to tote up IQ points. You're probably already playing with pretty close to a full deck—Ritalin or water aren't going to make much of a difference. What you've got going already is about as good as it gets.

Image Source: Alex Anlicker