After reviewing two neural imaging studies recording brain activity, U of T researchers suggest that people, if given the same reward, prefer to tell the truth to achieve the reward rather than to lie.

“Our findings together show that people typically find truth-telling to be more rewarding than lying in different types of deceptive situations,” says U of T professor Kang Lee.

Each study covered a different type of deceptive behaviour between a liar and a lie receiver. The first study involved the lie receiver being unaware that the liar was lying. The second study involved the receiver being aware of the lie, much like bluffing in poker. In both cases, telling the truth generated more activity in the liar’s cortical reward system than lying.

The research also suggested that lying is more demanding on the brain than truth-telling because lying causes more brain activation in the frontal lobe.