Many American men might blanche to recall dangerous moments on the road as a newly licensed teenage driver.

Though science has long known that younger men are overrepresented among crashes and roadway fatalities, new research from the University of Turku in Finland shows how the brain’s maturation process influences behavior behind the wheel. In a laboratory study last year, researchers scanned the brains of 34 young volunteers playing car racing video games.

Dagfinn Moe, a senior researcher with independent research group SINTEF, has for years studied the risk-taking behavior of adolescents and young adults in work that draws from neurobiology, psychology, and the social sciences. For the study, he and his colleagues made a comparison between 17 risk-averse volunteers and another 17 with a lower tolerance for risk, as measured by psychology tests. A higher tolerance for risk is generally associated with the maturing brain of the adolescent, as evidenced by myriad research studies.

Here, volunteers drove their simulated vehicles along a section of road at a pre-set speed before eventually coming to a junction presenting two options: to run the yellow light and risk a crash, or wait three seconds before preceding.

“If he runs a yellow light causing a collision, he has to wait six seconds before driving on. It takes three seconds to stop and wait for green, so by far the fastest way of completing the course is to run yellow lights without colliding,” Moe said in a statement describing the experiment.

As shown through brain scanning technology, the biological mechanism controlling human decision-making lies within the brain’s frontal lobe. However, the brain considers other information — including the emotions — before making a decision. In that process, two-way communication occurs between the limbic system and frontal lobe.

"All our lives we have to make balanced decisions, and emotions of all kinds are always linked to this process,” Moe said. “In many cases our emotions will take the upper hand, causing us to take risks and act rashly and foolishly.”

Among young men in the study with a higher tolerance for risk, cognition was apparently dominated by motivation and emotion, effectively “blinding” the young driver to the inherent risks of driving a motor vehicle. "Risk-averse drivers consider and balance their assessments to a much greater degree before they decide whether to stop or drive on,” Moe said. "The high-risk group is dominated by motivation and emotions encouraging them to take a chance and drive on regardless — and experiences no decisive dilemma when approaching the yellow light.

Interestingly, the researchers also found that those in the higher-risk group experienced a quicker maturation of neural networks known as “white matter” connecting various areas of the brain. Though it might seem paradoxical, Moe said, higher tolerance for risk is sometimes associated with heightened brain activity — no matter how “stupid” the decision’s outcome.