We've come up with a method to start answering scientific questions about how people make decisions involving sacred values, and that has major implications if you want to better understand what influences human behavior across countries and cultures," Berns says. "We are seeing how fundamental cultural values are represented in the brain."

The researchers used functional magnetic resonance imaging (fMRI) to record the brain responses of 32 U.S. adults during key phases of an experiment. In the first phase, participants were shown statements ranging from the mundane, such as "You are a tea drinker," to hot-button issues such "You support gay marriage" and "You are Pro-Life." Each of the 62 statements had a contradictory pair, such as "You are Pro-Choice," and the participants had to choose one of each pair.

At the end of the experiment, participants were given the option of auctioning their personal statements: Disavowing their previous choices for actual money. The participants could earn as much as $100 per statement by simply agreeing to sign a document stating the opposite of what they believed. They could choose to opt out of the auction for statements they valued highly.

"We used the auction as a measure of integrity for specific statements," Berns explains. "If a person refused to take money to change a statement, then we considered that value to be personally sacred to them. But if they took money, then we considered that they had low integrity for that statement and that it wasn't sacred."

The brain imaging data showed a strong correlation between sacred values and activation of the neural systems associated with evaluating rights and wrongs (the left temporoparietal junction) and semantic rule retrieval (the left ventrolateral prefrontal cortex), but not with systems associated with reward.

"Most public policy is based on offering people incentives and disincentives," Berns says. "Our findings indicate that it's unreasonable to think that a policy based on costs-and-benefits analysis will influence people's behavior when it comes to their sacred personal values, because they are processed in an entirely different brain system than incentives."