Most people prefer to have their rewards immediately, rather than have to wait for them, but would what if the rewards of the future are greater than the rewards available now - would you be prepared to wait? What if you were offered £20 now, or you could wait and have £100 in six months time - what would you choose? Being able wait for more valuable rewards is associated with higher intelligence, and now researchers believe they have found a region of the brain that is involved in both intelligence and what psychologists call "delay discounting" - the inability to resist the temptation of a smaller reward in lieu of recieving a larger reward at a later date. Discounting future rewards too much is a form of impulsivity, and an important way in which we can neglect to exert self-control.