ATLANTA -- It's nicer when you actually earn it.
Lottery winners, trust-fund babies and others who get their money without working for it do not get as much satisfaction from their cash as those who earn it, a study of the pleasure center in people's brains suggests.
Emory University researchers measured brain activity in the striatum - the part of the brain associated with reward processing and pleasure - in two groups of volunteers. One group had to work to receive money while playing a simple computer game; the other group was rewarded without having to earn it.
The brains of those who had to work for their money were more stimulated.
"When you have to do things for your reward, it's clearly more important to the brain," said Greg Berns, associate professor of psychiatry and behavioral science. "The subjects were more aroused when they had to do something to get the money relative to when they passively received the money."
Berns and other researchers said the study has broader real-world implications, particularly in the age of multimillion-dollar lottery jackpots.
He said that other studies have shown "there's substantial evidence that people who win the lottery are not happier a year after they win the lottery. It's also fairly clear from the psychological literature that people get a great deal of satisfaction out of the work they do."
In the Emory study, published Thursday in the journal Neuron, volunteers played a computer game in which they had to push a button every time a triangle appeared. The 16 volunteers played while their brains were scanned by a magnetic resonance imaging machine, or MRI.
The researchers found that some reward centers of the brain were activated whenever a volunteer received money. However, the striatum was activated only when volunteers worked for their reward.
Berns suggested that the brain is wired this way by nature.
"I don't think it ever evolved to sit back and sit on the couch and have things fall in our laps," he said.
The study was funded by the National Institute on Drug Abuse.
"This part of the brain is a fascinating part. It's associated with drug abuse, a number of diseases," Berns said. "It's no coincidence we're finding it to be very important in almost everything that we do."