Teenagers tend to test the waters differently than children and adults are willing to, and after decades of investigation science has come to find a unique architecture and function within their brains. Researchers from University College London added to a growing body of knowledge by studying how teenagers make judgment calls and who is responsible for influencing their decisions. The study, published in the journal Psychological Science, reveals a clear link between the impact peers can have on a developing mind.

"Young adolescents were more strongly influenced by other teenagers than by adults, suggesting that in early adolescence the opinions of other teenagers about risk matter more than the opinions of adults," the study’s lead author Dr. Lisa Knoll, a researcher from UCL Institute of Cognitive Neuroscience, said in a press release. "Our findings suggest that the target of public health interventions should be adolescent social norms, rather than simply focusing on the potential health risks associated with certain situations and choices."

Researchers asked 563 people between the ages of 8 to 59 to rate the risk levels of certain everyday situations such as crossing the road, approaching a red light, or taking a shortcut through a dark alleyway. When they looked at the participant risk ratings, researchers found all age groups were socially influenced by what others said regardless of the other people’s ages. Teenagers were the least likely to change their minds when someone else assessed risk differently than they did, although if they did change their mind it was most likely because their peers did.

"As people get older, they become more confident in their own judgement of risk and less swayed by other people," study’s senior author Sarah-Jayne Blakemore, a professor from UCL Institute of Cognitive Neuroscience, said. "We know that adolescents are more likely to take risks when with peers than alone. Our study showed that young adolescents do not perceive situations as less risky than older age groups, but do tend to change their risk perception in the direction of the opinions of similar aged peers. So other teenagers' opinions about risk seem to influence young adolescents into judging a situation as less risky than they originally thought it was."

On top of risk assessment, teenagers are just naturally drawn toward unknown risks more than known risks, according to a 2012 study published in the conducted at the University of California, Santa Barbara. They found teenagers are at twice the risk of dying than when they were preteens. Their perception of risk is different than an adult’s, but not what you’d expect. Teens actually overestimate risk like unprotected sex and drug use, but what draws them to cross the line into uncertainty is their greater tolerance for it. Unknown risks conform well to teens, who have highly flexible brains designed to learn and adapt.

Put your finger on the top center part of your forehead — sitting on the other side of your skull is your prefrontal cortex (PFC), and it may be responsible for a lot of the irresponsible decisions you’ve made in your life. Think of the brain like a muscle that must be flexed and exercised in order to develop. The PFC is ultimately the CEO of the brain that controls, plans, works from memory, organizes, regulates mood, and assesses risk. It begins to grow again right before a child hits puberty, and as it grows teenagers learn to reason better, develop more control over impulses, and make judgments better, according to the National Institute of Mental Health. But it needs to still grow, and in order to do that teenagers take notes from their environment and the people inside of it.

Source: Knoll L, Blakemore SJ. Psychological Science. 2015.