David DiSalvo's newest book, Brain Changer, is now available at Amazon, Barnes and Noble and other major booksellers.
Comply. That’s an uneasy watchword at the very center of social cohesion. Without enough social norm compliance—such as the norm that stresses fairness in our dealings with others—humans aren’t great at getting along. The question is, what’s at the heart of our willingness to comply with social norms? Are our brains pre-packaged with compliance wiring? Or do we bend to the dictates of fairness and equal treatment only because our laws press us into compliance? Or is it some of both?
Neuroscientists are quite interested in these questions, and they’ve even made some progress answering them. Studies using functional magnetic resonance imaging (fMRI) have identified brain areas that appear to be involved in our decisions about when and why we treat others fairly or unfairly. These studies have shown, for example, that a region in the right hemisphere of the brain called the right lateral prefrontal cortex (rLPFC) is activated when people comply with social norms (or "rules"), suggesting that the rLPFC is an important part of a neural network that could be considered our brain’s social-norm wiring. But as with all fMRI results, brain activity does not conclusively prove a causal relationship between a given brain area and a given behavior—the results can only suggest it.
A new study from researchers at the University of Zurich took all of this a big step forward by using a painless and harmless electrical charge to positively or negatively stimulate the rLPFC (something called “transcranial direct current stimulation”) while study participants took part in a computerized fairness game.
The game works like this: participants are given an amount of money and told to share it with a randomly assigned partner. In one game scenario, they are allowed to make the decision of how much money to give away without the threat of a penalty for being unfair. In another scenario, they are told they can still make the decision, but their partner will be able to penalize them if they act unfairly.
In the first phase of the study, participants played the fairness game without experiencing the electrical charge. The social norm of fairness dictates that people give away an equal or near equal portion of the money, but without the threat of a penalty most participants only gave away between 10-25% of their stash. With the threat of a penalty, the percentage increased to between 40-50%.
Researchers then had the participants play the game again, but this time while experiencing a positive electrical charge designed to increase activity in the rLPFC. Participants receiving the positive charge increased the amount of money they gave away by about 33%. When researchers switched to a negative charge (which decreased rLPFC activity), participants decreased the amount they gave away by about 22%.
But here’s the twist: these results only held true when a penalty was threatened. Without threat of a penalty, the positive and negative charges to the rLPFC actually had an opposite effect. Researchers also checked to see if the electrical charges changed the participants’ expectation of how strong or weak the penalty would be, and found no change in threat expectation.
What this means is that stimulating the brain region didn’t make people fairer -- it made them more sensitive to threats of being punished if they didn’t act fairly.
The implications of this finding are potentially massive, and more than a little alarming. If we can biochemically alter activity in the rLPFC with a pill, just as these researchers did with an electrical current, then we’re looking toward a brave new pharmacological world that serves up a daily dose of compliance via threat sensitivity (assuming, of course, that there might be a market for such a drug). On a more positive note, the finding opens a door to treat people with damage to their rLPFC, who may be dangerously non-compliant with social norms.
However you choose to view the results, the research is significant because it bridges a chasm between seeing brain activity in relation to a behavior (in an fMRI brain scan) and changing behavior by manipulating brain activity. And while that's also a little frightening, it's a necessary step toward figuring out where ambiguous concepts like "social norm compliance" play out in the brain. This study is just a tiny taste of what's to come.