Sir

Henry Greely and colleagues call for answers to several controversial questions regarding the use of drugs by healthy people to boost cognitive performance ('Towards responsible use of cognitive-enhancing drugs by the healthy' Nature 456, 702–705; 2008). The most important scientific and ethical concern they raise is safety, not least because the pressure that leads people to enhance their performance might also be a crucial trigger to mental disorder. This is particularly likely when combined with sleep deprivation and anxiety caused by aggressive competition, as we have already learned from the indiscriminate use of amphetamines.

However, it would not be surprising if the repurposing of these drugs has less of an impact than expected by some and feared by others. Myriad personality traits are just as important as memory or 'intelligence' in the overall scheme of a successful life. Studies of gifted or 'savant' children show that self-confidence, discipline, focus, drive, resilience and social skills are highly complex personality traits, often found in successful people (see, for example, E. Winner Gifted Children: Myths and Realities; Basic Books, 1996).

Using medications to improve cognitive performance might be relevant in the short term. But a fully successful future will always depend on two very singular human features: eagerness to excel and setting a high standard of achievement.

See also Risks and benefits may turn out to be finely balanced A medical view of potential adverse effects Recall of learned information may rely on taking drug again Patterns of drug use have varied throughout history Careful use helps me do better research, and society benefits Enhancement means a broader role for physicians