What’s on your mind when you go to university?

How your still-developing brain puts you at risk

What’s on your mind

Illustration by Ian Phillips; Photo Illustration by Taylor Shute

Updated Jan. 18, 2018

Heading off to university is a time-worn rite of passage, one that marks the transition from teen years to adulthood. Despite the new relationships, responsibilities and independence that come with leaving home, however, in our late teens and early twenties, we’re still not fully mature. Our brains keep developing well into these years.

When puberty hits, brain regions responsible for reward and pleasure kick into high gear, according to Temple University psychology professor Laurence Steinberg, author of You and Your Adolescent. But other regions, involved in decision-making and impulse control, are slower to develop—and don’t mature until our mid-twenties. “The accelerator is activated before there’s a good braking system in place,” he says. Teens in mid-to-late adolescence are prone to risky decisions, seeking rewards without weighing the consequences. Starting a new life on campus, these brain changes affect students’ lives in all sorts of ways—maybe pushing them to stay out drinking all night, sign up for a semester abroad in Europe, sleep right through class, or ask their crush out on a date.


Your internal clock has shifted, pushing you to stay up later—but it might be better to sleep through that first class, or better, sign up for later classes. Sleep is crucial now for brain development. Chronic lack of sleep might even hinder the growth of brain synapses, according to a new study from U.S. researchers.


You’re used to multitasking: you’ll do homework while checking Facebook and chatting online. But too much multitasking can cause information overload, when the brain’s decision-making faculties freeze up, causing stress. Young adults, whose brains are still developing, are especially vulnerable.


Binge drinking is a very risky behaviour, but if that doesn’t stop you, consider this: alcohol and drugs have a greater impact on the brain during adolescence “in terms of permanent brain change,” Steinberg says. With the brain still under development, it can increase a person’s chances of becoming addicted later.


You’re more prone to take a gamble when you’re with friends. Steinberg and colleague Jason Chein studied teens’ brain activity while they played a driving game. When teens were with friends, they were more likely to speed through a yellow light; their brain regions associated with reward showed more activation, too.


With raging hormones, newfound freedom and a brain that’s wired for risky behaviour, you’re more likely to engage in unprotected sex. The number of young people doing so in Western countries jumped in the last two years, according to a new survey. In the U.S., it went from 38 per cent in 2009 to 53 per cent today.

Mental health

As if our adolescent years weren’t difficult enough, this is when we’re most sensitive to mental illness. “We think some of it has to do with brain development,” Steinberg says. “Most people who suffer from depression as adults have their first episode as adolescents.”


Taking a chance is often a good thing now: your brain is programmed for it, and these years are marked by experimentation. “We want people to be able to get on stage in high school and act in a play,” says Steinberg. “Or take a class they haven’t taken before. Or ask somebody out, even if they’re nervous to call them.”

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