Monkeys are eager to gain new information, even if there are no immediate benefits, a new research has found.
The findings offer insights into how a certain part of the brain shared by monkeys and humans plays a role in decision making, and perhaps even in some disorders and addictions in humans, researchers said.
The study, by researchers at the University of Rochester and Columbia University, shows that rhesus macaques have such robust curiosity that they are willing to give up a large portion of a potential prize in order to quickly find out if they selected the winning option at a game of chance.
In the study published in the journal Neuron, monkeys were presented with a video gambling task in which they consistently chose to learn in advance if they picked the winning option.
The monkeys did not receive their prize any sooner, which was a measure of juice or water; they were simply informed immediately if they selected a winner.
"When it's simply a choice between getting the information earlier or not, the monkeys show a pretty strong preference for getting it earlier," said lead researcher Tommy Blanchard, a PhD candidate in the lab of Benjamin Hayden, co-senior author of the study and professor in brain and cognitive sciences at the University of Rochester.
In the video gambling experiments, graduated coloured columns illustrated the amount of water that could be won. The monkeys were more curious about the gambles when the stake - or columns - were higher.
The researchers found the monkeys not only consistently selected the gamble that informed them if they picked a winner right away, but they were also willing to select that option when the winnings were up to 25 per cent less than the gamble that required them to wait for the results.
According to the researchers, their study helps to build a broader understanding for how curiosity - information seeking - is processed and rewarded in the brain.
Like monkeys, when curious we evaluate what we'd be willing to pay or give up to satisfy our curiosity, Hayden said.
In the case of gambling, there is also the potential of a prize to factor in. So when we make a choice, it depends on the sum of those two things: the gamble (the money you might win), and the value of finding out. And those two things need to be combined in order to make decisions about that gamble.
Earlier work suggests that these components are combined in the brain's dopamine system. This study looks at one step earlier in the process, in a region of the brain called the Orbitofrontal cortex, or OFC.
"I think of the OFC as the workshop of economic value, where, in this case, you have the value of the gamble and the value of the information - the raw materials - but they haven't yet been combined," said Hayden.
"This study seems to have revealed that the mixing of the raw materials happens somewhere between the OFC and the dopamine system. We now have two points in the circuit," Hayden said.