He first took up the game in 1995, when he was in college. He recalled: "It was very mathematical, but you could also inject yourself into the game and manipulate the other guy with words" - more so than in a game like chess. Phillips soon felt that he had mastered the strategic aspects of poker. The key variable was execution. At tournaments he needed to be able to stay focused for 14 hours at a stretch, often for several days, but he found it difficult to do so. In 2003, a doctor gave him a diagnosis of ADHD and he began taking Adderall. Within six months, he had won $1.6m at poker - far more than he'd won in the previous four years. Adderall not only helped him concentrate, it also helped him resist the impulse to keep playing losing hands out of boredom. In 2004, Phillips asked his doctor to give him a prescription for Provigil, which he added to his Adderall regimen. He took 200-300mg of Provigil a day, which he felt helped him settle into an even more serene and objective state of mindfulness; as he put it, he felt "less like a participant than an observer - and a very effective one". Though Phillips sees neuroenhancers as essentially steroids for the brain, they haven't yet been banned from poker competitions.

Gibson and Green (2002), talking about a possible link between glucose and cognition, wrote that research in the area …is based on the assumption that, since glucose is the major source of fuel for the brain, alterations in plasma levels of glucose will result in alterations in brain levels of glucose, and thus neuronal function. However, the strength of this notion lies in its common-sense plausibility, not in scientific evidence… (p. 185).
Nootropics (/noʊ.əˈtrɒpɪks/ noh-ə-TROP-iks) (colloquial: smart drugs and cognitive enhancers) are drugs, supplements, and other substances that may improve cognitive function, particularly executive functions, memory, creativity, or motivation, in healthy individuals.[1] While many substances are purported to improve cognition, research is at a preliminary stage as of 2018, and the effects of the majority of these agents are not fully determined.