[Paleopsych] NYT: Update: The Evidence on Revenge Mounts

[Premise Checker]

Update: The Evidence on Revenge Mounts
NYT August 31, 2004
By MARY DUENWALD

The evidence is increasing that revenge in fact brings
pleasure. In the latest study, players who were unfairly
treated in a game involving money, trust and cooperation
got a measurable kick out of punishing their partners.

The study, by researchers at the University of Zurich, was
published in the Aug. 27 issue of Science. In the game, two
male participants who did not know each other were each
given 10 units of money. Player A could either give his
money to Player B or keep it. If he gave it away, the
amount would be quadrupled, so that Player B would end up
with 50 units (his own units plus the 40 from Player A).
Then Player B was told to decide whether to share his
bounty with Player A.

In almost all trials, Player A gave away his money,
trusting Player B to share. But often Player B did not
share, in which case Player A was given time to decide how
to react - by doing nothing or reducing Player B's payoff
by anywhere from 2 to 40 units.

Using positron emission tomography (PET) scans, the
researchers saw that as players came to a decision to
punish greedy partners, the striatum, a part of the brain
involved in processing rewards, was activated.

That part of the brain - located a short distance behind
the bridge of the nose - is involved in reward processing.
It is activated, for example, when a person is in love and
sees a photograph of his beloved, when someone thinks he
will soon be paid money, or when someone takes cocaine,
said Dr. Ernst Fehr, an economist and co-author of the
study.

Sometimes, Player A had to pay for the privilege of
exacting revenge, giving up one unit of money for every two
he deducted from Player B. The more activated Player A's
striatum had been when he punished for free, the more he
was willing to pay to punish later on.

"Our results indicate why revenge is deeply entrenched in
many societies," Dr. Fehr said.

http://www.nytimes.com/2004/08/31/health/31upda.html