The New Yorker on the underground world of “neuroenhancing” drugs.

Margaret Talbot of The New Yorker wrote a piece about people who use old and new types of amphetamines to boost alertness and concentration. Cephalon, the Provigil manufacturer, has publicly downplayed the idea that the drug can be used as a smart pill. In 2007, the company’s founder and C.E.O., Frank Baldino, Jr., told a reporter from the trade journal Pharmaceutical Executive, “I think if you’re tired, Provigil will keep you awake. If you’re not tired, it’s not going to do anything.” But Baldino may have been overly modest. Only a few studies have been done of Provigil’s effects on healthy, non-sleep-deprived volunteers, but those studies suggest that Provigil does provide an edge, at least for some kinds of challenges. In 2002, researchers at Cambridge University gave sixty healthy young male volunteers a battery of standard cognitive tests. One group received modafinil; the other got a placebo. The modafinil group performed better on several tasks, such as the “digit span” test, in which subjects are asked to repeat increasingly longer strings of numbers forward, then backward. They also did better in recognizing repeated visual patterns and on a spatial-planning challenge known as the Tower of London task. (It’s not nearly as fun as it sounds.) Writing in the journal Psychopharmacology, the study’s authors said the results suggested that “modafinil offers significant potential as a cognitive enhancer.” Brain Gain: The underground world of “neuroenhancing” drugs...