De Martino and colleagues asked 20 men and women to undergo three 17-minute brain scans while being asked to gamble — or not — with an initial pot of English pounds worth about $95. When told they would "keep" 40% of their money if they didn't gamble, the volunteers chose to gamble only 43% of the time. Told they could "lose" 60% of the money if they didn't gamble, they rolled the dice 62% of the time.via USA Today
Their chances of winning the money were carefully explained beforehand, and participants knew the odds were identical. But the framing effect still skewed their decisions significantly.
The brain images revealed the amygdala, a neural region that processes strong negative emotions such as fear, fired up vigorously in response to each two-second (on average) gambling decision. Where people resisted the framing effect, a brain region connected to positive emotions such as empathy, and another that activates whenever people face choices, lit up as well, seeming to duke it out over the decision.