Life

The Science Behind Peer Pressure

by Brianna Wiest

While we already knew that the people you spend your time with have an incredible impact on how you behave, what you think, and who you are, new research is highlighting that fact that risk taking behavior is contagious — for better and for worse. When determining what it is that influences us to take risks or play it safe, it's a matter of something called the "contagion effect". A new study conducted by Caltech researchers explored the neural mechanism of this, and the results are surprising.

The study, led by John O'Doherty, a professor of psychology at the Caltech Brain Imaging Center, used 24 volunteers to participate in three kinds of trials. First was a "self" trial, where the participants were asked to choose between taking a guaranteed $10 or making a gamble for a higher payoff; a "predict" trial, where the participants were asked to predict the risk-taking tendencies of an observed peer; and then the "observe" trial, in which participants studied the actions of their peers. The results were conclusive in determining that people who observe riskier behaviors are more inclined to make them, too. "By observing others behaving in a risk-seeking or risk-averse fashion, we become in turn more or less prone to risky behavior," said Shinsuke Suzuki, study author and a postdoctoral scholar in neuroscience.

The results allowed the researchers to determine that there is actually a part of the brain, called the caudate nucleus, which responds to risk. This was determined by observing that gambling correlated with an increase in activity in this part of the brain. "This showed that, in addition to the behavioral shift, the neural processing of risk in the caudate is also altered. Also, both the behavioral and neural responses to taking risks can be changed through passively observing the behavior of others," Suzuki says.

Researchers then found that there was a connection between the caudate nucleus and a part of the brain that would control the strength of the "contagion effect," which essentially means that there's more at play here than just observed behavior and response. People are more susceptible to risk-taking based on their own predisposition (which is more obvious than not). "Our findings provide insight into how observation of others' risky behavior affects our own attitude toward risk," Suzuki said. "The tendency of financial markets to collectively veer from bull markets to bear markets and back again could arise, in part, due to the contagion of observing the risk-seeking or risk-averse investment behaviors of other market participants."

The findings will be published in the March 21 edition of the Proceedings of the National Academy of Sciences, and the paper itself will be called "Behavioral contagion during learning about another agent's risk-preferences acts on the neural representation of decision-risk." The researchers hope that it will be a gateway to exploring more about the function of how brain circuits go awry, informing us more about issues like social anxiety, autism and other disorders. The research was funded by the Japan Society for the Promotion of Science Postdoctoral Fellowship for Research Abroad and the Caltech Conte Center for the Neurobiology of Social Decision Making, which is supported by the National Institute of Mental Health.

So just remember, the next time someone asks you, "If everyone jumped off a bridge, would you do it too?" Your brain might be all NO, but your caudate nucleus might be like, yesyesyes. Stay safe!

Images: Unsplash; Giphy