Extension of our 'natural' capacities through science and technology is not a new phenomenon – it has been a key driver of many evolutions of human society throughout history: movement with the wheel; navigation with the compass; communication with the wire. The field of 'neuroenhancement' – using our understanding of how the brain works more directly to try to improve the way it functions – might well be the next such catalyst.

Our new research reviewing the cognitive effects of the "smart pill" modafinil has found that it can improve the performance of healthy people on cognitive tasks, meaning it can be considered the first of these "neuroenhancement agents". But, what is also clear is that we need to radically improve the way that we analyse the effect this kind of drug has on both healthy brains and wider society.