‘Why do we do this?” asks Jim Stark in Rebel Without a Cause, seconds before a deadly car race. “You’ve gotta do something, don’t you?” is the reply.

Now, 50 years later, psychology is ready to offer Jim a more satisfactory explanation. Science is exploring the adolescent brain, that most inscrutable of organs, and the results could save millions.

The real answer to Jim’s question is steeped in complicated neuroscience, but boils down to one simple factor: peer pressure.

That is the view of Prof Laurence Steinberg, of Temple University, Philadelphia. Prof Steinberg has investigated the biological basis for risk taking in adolescence.

Prof Steinberg let teenagers take control in a driving simulation. “The player is encouraged to drive as far as he can in a fixed amount of time,” he explains.

“Along the way, the player encounters eight traffic lights that turn yellow as he approaches the intersection.”

The player is faced with a dilemma: stop and waste time, or risk crashing at the junction. “When adolescents play the game, they take twice as many chances if their peers are in the room than if they are by themselves,” says Prof Steinberg. “No such peer effect is seen among adults.”

The strong association between peer pressure and risk taking may be a side-effect of brain development. During adolescence, two brain networks emerge: the cognitive-control and the socio-emotional.

The cognitive-control network encourages us to take sensible decisions by weighing up the pros and cons of our actions, judging possible rewards against potential risks. The socio-emotional network helps us deal with social situations and emotions, but is linked to reward processing.

When the network is active it can cloud our judgment by amplifying the appeal of a reward. Our judicious self is drowned out by impulse.

By adulthood, the struggle between recklessness and restraint is all but won. The cognitive-control network ensures we act with prudence, even at times of high emotion. But the networks mature at different rates.

Cognitive-control is underdeveloped in adolescence. The teenager’s socio-emotional network is likely to govern behaviour, especially at times of social interaction or intense emotion.

The prospect of a reward acquires such an allure that it impairs risk perception. Because peer pressure involves a potent mix of high emotion in a social group, it leaves adolescents at the mercy of their rash self.

They decide that completing the driving game in the quickest time and gaining the respect of their peers is more important than avoiding a crash…

Source: Telegraph.co.uk, United Kingdom
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