It's official: Money can't buy happiness. Sure, if a person is handed $10, the pleasure centres of his brain light up as if he were given food, , or drugs. But that initial rush does not translate into long-term pleasure for most people. Surveys have found virtually the same level of happiness between the very rich individuals on the Forbs 400 and the Maasai herdsmen of East Africa. Lottery winners return to their previous level of happiness after five years. Increases in income just don't seem to make people happier-and most negative life experiences likewise have only a small impact on long-term satisfaction. "The relationship between money and happiness is pretty darned(非常)small," says Peter Ubel, a professor of medicine at the University of Michigan. That's not to say that increased income doesn't matter at all. There is a very small correlation between wealth and happiness-accounting for about one percent of the happiness reported by people answering the surveys. And for some groups, that relationship may be considerably bigger. People who are poor seem to get much happier when their monetary prospects improve; so do the very sick. In these cases, Ubel speculates, people may be protected from negative circumstances by the extra cash. Another possibility is that the money brings an increase in status, which may have a greater impact on happiness. Why doesn't wealth bring a constant sense of joy? "Part of the reason is that people aren't very good at figuring out what to do with the money," says George Loewenstein, an economist at Carnegie Melton University. People generally overestimate the amount of long-term pleasure they'll get from a given object. Sometimes, Loewenstein notes, the way people spend their money can actually make them less happy. For example, people derive a great deal of pleasure from interacting with others. If the first thing lottery winners do is to quit their job and to move to a palatial(富丽堂皇的)but isolated estate where they don't see any neighbours, they could find themselves isolated and depressed.