DURHAM, NC - "Make it a rule of life never to regret, and never to look back." - fine words from Katherine Mansfield, but ones she clearly forgot to pass on to the monkeys.
In one of those inspired bits of research we love so much, a team at Duke University trained a group of rhesus macaques to play a game based on Deal or No Deal.
The researchers gave the macaques a choice of eight white squares to pick up. Underneath each was a colour representing a prize, with green bringing the best reward - a sugary drink. After picking a square, the animals were shown the prizes they had passed up.
The test was similar to the television show Deal or No Deal, where contestants are asked to choose amongst boxes containing dofferent amounts of money. As the game progresses, they learn what they could have won by choosing differently.
Brain scans revealed activity in the anterior cingulate cortex (ACC), a region known to monitor the consequences of actions when the monkeys won a prize. But the same area also lit up when they were shown what they had missed, indicating that they were thinking about what might have been.
The researchers say that the test was more than just a way of filling a rainy Friday afternoon. They say that the results show that the macaques can reason about abstract things, and thus have the basis of a philosophical perspective.
"This is the first evidence that monkeys, like people, have 'would-have, could-have, should-have' thoughts," said Ben Hayden, a researcher at the Duke University Medical Center and lead author of the study.
The study will be published in the journal Science.