'Fragile circuitry' in the teenage brain allows for risk-taking

Any risky behaviour teens do — whether texting while driving, a common occurrence, according to a new study — should not be a complete surprise given the complex inner biology of the teenage brain that science is mapping out.

Adolescents more likely to act impulsively and trust gut feelings

Almost half of licensed drivers in Grade 10 to 12 in Ontario have texted while behind the wheel, a new survey says. (Shutterstock/Sean Locke Photography)

Common sense would suggest that it's not really wise to dash off a text while driving or ride a bike without wearing a helmet, yet a recent study suggests a lot of Ontario teens have done just that.

In their defence, scientists are finding that the complex inner workings of the teenage brain have not developed fully, so perhaps that risky behaviour should not be a complete surprise.

"Current thinking believes that our brains do not become mature until the early- to mid-20s," said Lin Fang, an associate professor at the University of Toronto's Factor-Inwentash Faculty of Social Work.

"For adolescents, their frontal cortex — the region that governs decision-making, reasoning, insight and judgment — is still undergoing development."

In addition, scientific evidence suggests that teens handle emotions, along with stressful and risky situations, differently from adults, Fang said in an email.

"As such, they are more likely to engage in impulsive acts and trust their gut feelings when they are faced with difficult or stressful situations."

The 2013 Ontario Student Drug Use and Health Survey, a biennial study done for the Centre for Addiction and Mental Health, found that more than one-third of licensed drivers in Grades 10 to 12 say they had sent a text while behind the wheel.

As well, up to 79 per cent of teen cyclists said they don't always wear a helmet, while slightly more than half said they rarely or never don the protective headgear.

Trying to do something well

Youth angst is hardly a new phenomenon. But scientists do see it playing a significant role in the behaviour of teens as they are trying to find their own way in the world.

"It really is a challenging time for families and for young people as they develop their skills around conflict and conflict resolution and problem solving," said Dr. Joanna Henderson, a psychologist, clinical scientist and head of research in CAMH's child, youth and family program.

Teen behaviour that may appear risky to adults may in fact just be examples of teenagers trying to sort out how to solve their own problems.

"If we think of any other behaviour, if we think of riding a bike, any sports, music, practice is a really important piece of being able to do something well," said Henderson.

A new study from local researchers has found walk-in therapy clinics are more effective at helping people work through their problems than traditional sessions. (Paulius Brazauskas/Shutterstock)

"Throughout adolescence, teenagers are really interacting with their environment in ways that often are experienced by parents as conflict or taking risks, but at some level are also opportunities for young people to practice and establish their own problem-solving skills, their own independent decision-making skills."

Key to helping teens make good decisions is to start early, said Henderson, not to wait for adolescence to set in before trying to set an example.

"Decision making is an internal process, so if parents aren't saying aloud how they're coming to decisions, kids don't have the opportunity to learn from that process."

In the case of texting while driving, for example, parents shouldn't be doing that if they don't want their kids to do it either. (It may not be easy. Some CBC readers feel it is a common occurrence, no matter the age of the driver.)

Anxiety and fear

Teen anxiety and fear — mixed with that maturing brain biology — may also heavily influence how youth behave.

"It turns out that the brain circuit for processing fear — the amygdala — is precocious and develops way ahead of the prefrontal cortex, the seat of reasoning and executive control," Richard Friedman, a professor of clinical psychiatry and director of the psycho-pharmacology clinic at the Weill Cornell Medical College, wrote recently in the New York Times in a piece headlined "Why Teenagers Act Crazy."

"This means that adolescents have a brain that is wired with an enhanced capacity for fear and anxiety, but is relatively underdeveloped when it comes to calm reasoning."

Beyond the biology, and the fact that the teenage brain hasn't reached full maturity, the potential for teens to engage in risky behaviour may also be influenced by the additional stress they can face simply because of the many transitions happening in their lives.

This is the period when many are introduced to substances like tobacco, alcohol or marijuana, which may also be part of the risky behaviour impulse.

"When you can throw into that fragile circuitry that's just starting to form … significant stressors and trauma, and substance use specifically, it can certainly disrupt that process," said Chris Jackson, clinical lead for youth programming at the Canadian Mental Health Association.

'Walk the walk'

Parents often think that by adolescence, they have very little influence over their children. But "that is in fact not true," says Henderson.

"Youth are still keenly aware of their parents' behaviour as they have been throughout childhood, so parents really need to walk the walk."

Parents also need to set clear expectations, and indicate that if those expectations aren't met, there will be consequences.

"It has to be something that's a valued privilege for teenagers," says Henderson. "A natural consequence would be around restricting their access to the vehicle, for example."

Fang also suggests parents "should also pay attention to their children’s appetite, sleeping patterns, energy level, school performance and friendships."

The study done for CAMH also found that young girls reported they had thought about suicide at twice the rate of boys.

"Studies have shown that girls and boys respond to life stresses differently," said Fang, noting that girls are more likely to experience depression and anxiety disorders.

"Gender norms, hormonal changes during puberty and pressure from media and peers about their appearance are all possible factors to blame."

But, she said, while girls contemplate suicide more than boys do, boys are more likely to actually commit suicide.

"As such, it’s important to have gender-specific interventions that really target the specific risk and protective factors for each gender."


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