All on the Mind

"Provigil and Ritalin really do enhance cognition in healthy people. Provigil, for example, adds the ability to remember an extra digit or so to an individual's working memory (most people can hold seven random digits in their memory, but have difficulty with eight). It also improves people's performance in tests of their ability to plan. Because of such positive effects on normal people, says the report, there is growing use of these drugs to stave off fatigue, help shift-workers, boost exam performance and aid recovery from the effects of long-distance flights.

Earlier this year, Nature, one of the world's leading scientific journals, carried out an informal survey of its (mostly scientific) readers. One in five of the 1,400 people who responded said they had taken Ritalin, Provigil or beta blockers (drugs that can have an anti-anxiety effect) for non-medical reasons. They used them to stimulate focus, concentration or memory. Of that one in five, 62% had taken Ritalin and 44% Provigil. Most users had somehow obtained their drugs on prescription or else bought them over the internet."

http://www.economist.com/science/displaystory.cfm?story_id=11402761