Bluffing a computer: new study plays poker in an MRI

(CBS News) Humans give and receive hundreds of subtle (and not-so-subtle) social cues every day. Things like tone of voice, posture, eye contact and facial expression are processed by our brains in an attempt to "read" other people's moods. Any poker player will admit that they search for "tells" on their opponent's face to determine whether or not someone is bluffing. But what if you're playing against a computer?

A study published in this month's "Science" journal did just that. By strapping people into magnetic resonance imagers (MRIs) and having them play a simplified version of poker against computer and human opponents, researchers hoped to find out what part of the brain goes into bluffing.

The participants played a a form of poker with only one card and were matched against both human and computer opponents. Players were asked to keep track of their opponents' behavior when determining whether to bluff with a given card or not.

Researchers found that a certain part of the brain - the temporal-parietal junction, or TPJ - was active when deciding whether an opponent was bluffing. Interestingly, the TPJ has never previously been linked with social interaction. The study authors found a participant's TPJ was more active when they assumed that their opponent was particularly good at the game.

"We found that signals from the temporal-parietal junction provided unique information about the nature of the upcoming decision," the authors wrote in "Science."

Determining when someone is bluffing, and gauging their skill at poker, is a complex process in the brain. But the activity of the TPJ is a new avenue for exploring how our brains make decisions and read information. Long story short, expect a lot more poker games played in MRI tubes in the near future.