Reference: Yu, H., Siegel, J., Clithero, J., & Crockett, M. (2021). How peer influence shapes value computation in moral decision-making. Cognition, 211, 104641

Have you ever done something because a friend did it, even though you knew it was bad? Or maybe if your friends do something good, like donate money to charity, you also find yourself more inclined to give?

This notion of hanging with the ‘wrong’ or ‘right’ crowd was examined by a new study, which suggests that our moral actions, as well as our goals, are indeed influenced by the people around us.

Method

Recently, Drs. Hongbo Yu, Jennifer Siegel, John Clithero and Molly Crockett examined how people changed their behavior after viewing a peer make moral decisions: whether to profit from inflicting pain to a stranger.

The experiment consisted of three stages. First, participants made a series of decisions between getting different amounts of money for themselves and giving different amounts of painful electric shocks for a stranger (see the image to the right).

After completing this first part of the study, participants watched another ‘person’ (actually a set of preprogrammed decisions) complete the same set of decisions. Half of the participants watched a ‘good’ person, who required much more money to administer a shock, and half watched a ‘bad’ person, who required a small amount of money to give an additional shock to the stranger. Thus, the ‘good’ agent’s goal was to minimize harm to the other person by giving them the least amount of shocks possible, while the ‘bad’ agent’s goal was to maximize profits. While observing, participants also predicted what this person would do. Before seeing what the participant making the decision was going to do, participants were also asked to predict what they thought the decider would choose. This allowed the researchers to examine whether participants caught on to a person being ‘good’ or ‘bad’. 

After watching the other ‘person’ make these decisions, participants then completed the decision-making task again. This allowed the researchers to evaluate whether watching a peer influenced the way participants made decisions.

What did they find?

Good or bad, we’re influenced by our peers.
As expected, watching other people’s choices biased participants’ decisions to be more like those of their peers. Participants who watched and predicted the choices of a ‘good’ agent subsequently needed 38% more money per shock to deliver an extra shock to a stranger. Meanwhile, participants who watched the ‘bad’ agent required 31% less money to deliver extra shocks. 

Not only does behavior shift to be similar, but so do underlying goals.

As noted earlier, good agents were more focused on minimizing pain, while bad agents were most focused on maximizing profit. Using a computational model called the drift-diffusion model (DDM), which mathematically separates different components of a decision, the researchers were able to tease apart how much different participants focused on monetary rewards, versus number of given shocks. They found that after observing their peers, people shifted their focus in line with what the observed agent was focused on: participants who watched the good agent placed more weight on relative pain when weighing options in their decision making process. In contrast, participants who watched the bad agent placed greater focus on their own profits. 

The computational model also revealed that watching a good agent made the participants more likely to choose the selfless choice, even before seeing the specific options in each trial. On the other hand, observing a bad agent biased the participants’ choices toward the more selfish option.  

The authors note that this has implications for how we might try to influence people. Since selfish behavior was driven by focus on monetary gain, the authors suggest that drawing attention to harmful impacts on others could dampen or reverse this selfish focus. On the other hand, those who were acting selflessly were focused on the wellbeing of others. Therefore the authors argue that emphasizing personal benefits of morally good behavior may not motivate people. However, given that other motivators, such as seeing a potential increased personal benefit (respect, building reputation) were not present in this study, future research is needed to confirm these implications.

Similarity influences how much you are affected by the choices of your peers.

Next, the researchers further measured how two kinds of similarities, objective and subjective, influenced how strongly participants were influenced by their peers. Objective similarity referred to how similar the choices made by the peer and the participant were. In contrast, subjective similarity was obtained by asking participants how similar they felt to their peer. The researchers found that, the more participants felt and made similar choices to the morally good participant, the more emphasis they placed on minimizing harm. However, for participants who watched the morally bad participant, only objective similarity was associated with emphasis they placed on minimizing harm. 

We’re more aware of being influenced for the better. 

Finally, the researchers wanted to examine how aware we are of the influence that others’ have on us. Participants reported how explicitly aware they were of changes in their decisions after observing the peer. Strikingly, the self-awareness of peer influence of those who watched the good agent tracked more closely with the degree to which they were actually influenced, while reports from participants who watched the bad agents were unrelated to how much their decision making was actually influenced by their peer. The authors note here that bad behavior is therefore not only damaging because it causes others to behave less morally, but is also all the more insidious since we’re not aware of how much it can influence us.

These researchers provided evidence for old wisdom: ‘Bad company ruins good morals’. Not only do we shift our moral behavior to match our peers, but our internal focus also shifts. What’s more, the more similar you are to another person, both subjectively and objectively, the more likely they are to influence you, for better or for worse. And watch out, because we are just as likely to be influenced for the worse by our peers – but less likely to realize it.