I met Alex one evening last summer, at an appealingly scruffy bar in the New England city where he lives. Skinny and bearded, and wearing faded hipster jeans, he looked like the lead singer in an indie band. He was ingratiating and articulate, and smoked cigarettes with an ironic air of defiance. Alex was happy enough to talk about his frequent use of Adderall at Harvard, but he didn't want to see his name in print; he's involved with an internet start-up and worried that potential investors might disapprove of his habit.

The use of prescription stimulants is especially prevalent among students.[9] Surveys suggest that 0.7–4.5% of German students have used cognitive enhancers in their lifetime.[10][11][12] Stimulants such as dimethylamylamine and methylphenidate are used on college campuses and by younger groups.[13] Based upon studies of self-reported illicit stimulant use, 5–35% of college students use diverted ADHD stimulants, which are primarily intended for performance enhancement rather than as recreational drugs.[14][15][16] Several factors positively and negatively influence an individual's willingness to use a drug for the purpose of enhancing cognitive performance. Among them are personal characteristics, drug characteristics, and characteristics of the social context.[10][11][17][18]