"We discovered that the decision to follow the fairness norm, whether voluntarily or under threat of sanctions, can be directly influenced by neural stimulation in the prefrontal cortex."
Researchers asked the participants to participate in a classic sharing game:
"[T]hey received money and were asked to decide how much of it they wanted to share with an anonymous partner. A prevalent fairness norm in Western cultures dictates that the money should be evenly split between the two players. However, this contrasts with the participants’ self-interest to keep as much money as possible for themselves. In another experiment, the participants were faced with the same decision, but knew in advance that they could be punished by the partner for an unfair proposal."
Stimulating the right prefrontal cortex changed people's willingness to conform to social norms, but in odd, and seemingly contradictory ways depending on whether there was a threat of punishment:
When neural activity in this part of the brain was increased via stimulation, the participants’ followed the fairness norm more strongly when sanctions were threatened, but their voluntary norm compliance in the absence of possible punishments decreased. Conversely, when the scientists decreased neural activity, participants followed the fairness norm more strongly on a voluntary basis, but complied less with the norm when sanctions were threatened.
But is that because people's perception of the fairness of the game shifts as well? In short, no:
Moreover, neural stimulation influenced the participants’ behavior, but it did not affect their perception of the fairness norm. It also did not alter their expectations about whether and how much they would be punished for violating the norm.
What does this suggest? Researchers concluded that it is quite possible to know something is wrong, but be more or less likely to conform your behavior to that knowledge based on brain activity:
We found that the brain mechanism responsible for compliance with social norms is separate from the processes that represent one’s knowledge and beliefs about the social norm," says Ernst Fehr, Chairman of the Department of Economics at the University of Zurich. "This could have important implications for the legal system as the ability to distinguish between right and wrong may not be sufficient for the ability to comply with social norms." Christian Ruff adds: "Our findings show that a socially and evolutionarily important aspect of human behavior depends on a specific neural mechanism that can be both up- and down-regulated with brain stimulation."
This was a particularly interesting finding to me because sometimes I have felt like the reason I do wrong things is not because I don't know that they are wrong, but that I don't recognize in that moment that they are or I don't care about the particular consequences, i.e. no threat of punishment. I feel like I respond really well to incentives. If there is a very clear consequence I actually care about (e.g. the certainty of a dismemberment or the possibility of something good), my behavior will naturally maximize that incentive structure. It makes me wonder, if there are people like me who respond best to material consequences (high activity in this part of the brain?), are there people who respond best to just the thought of fairness and being a good person (low activity in this part of the brain?). Either way, I really like the point made at the end about the legal definitions of insanity not just for psychopaths, but for other disorders characterized by a failure to conform to social norms like Asperger's and others on the autism spectrum.
