The key to happiness

London: It has long been said that money cannot bring you happiness, but scientists have found that financial reward does make people feel good - especially when they know they are earning more than their peers.

Research showed that people are motivated by greed and only feel truly rewarded when they outdo their friends.

Scientists at the University of Bonn pitted pairs of men against each other over a series of games, promising to pay them according to their performance. Using brain scanning techniques, they found the men only truly felt happy and rewarded if they beat their partner and earned more money.

The researchers, Professor Christian Elger and Professor Armin Falk, studied the brain activity of 38 men as they played the games, side by side, performing the simple task of counting dots on a screen. What was fascinating, said Prof Falk, was that the effect of having more was not as strong as that of having less. "If you like, the pain of having less is stronger than the joy of having more." The implication of this work is that we are trapped on a "hedonic treadmill", as one sociologist put it, which means an endless effort to "keep up with the Joneses" to stay happy.