Teens Will Be Teens

Most adults are challenged when it comes to understanding teens' motives. "What were they thinking of?" is an all-too-common response. Without a doubt, no developmental period in our lives is more confounding and baffling than adolescence.

Until recently we blamed erratic teen behavior on raging hormones, but scientific research in the last decade has revealed that it's not hormones, but the brain itself that is the culprit. Jay Giedd, a neuroscientist at the National Institutes of Health (NIH) in Bethesda, MD, and the author of the first long-term study of the adolescent brain, used magnetic resonance imaging to scan the brains of 145 teens over two-year intervals. The scans revealed brains that are still in transition—works in progress—that won't be thinking logically and rationally until young adults reach their early twenties.

Before Giedd's findings, scientists had thought the brain was pretty much a "done deal" by adolescence. Although researchers knew that the brain of a baby grew by first over-producing brain cells and then severely pruning them at about age three, they didn't realize there was a second period of overproduction and pruning. It was Giedd's brain scans that revealed a spurt of growth in the prefrontal cortex just before puberty—about age 11 in girls, 12 in boys— and then a cutting back in adolescence.

The reason adults act adult-like is because they process information and make decisions with the prefrontal cortex. Residing just behind the forehead, that part of the brain acts as its CEO and is responsible for planning, organization, complex thinking, and impulse control. In contrast, teens' prefrontal cortexes are still immature. As a result, they're more apt to process information and make decisions with the amygdala, a small, almond-shaped structure at the back of the brain which is the home of impulsive, emotional, and instinctual behavior. As the prefrontal cortex matures, teens will reason better—but that's a slow process.

So what's a librarian to do? First, we need to understand what's going on in teens' brains and help them understand that, too. Many of the teen behaviors that adults find perplexing are, well, natural. Since that's the case, it's best to enjoy teens for who they are and help them in the process of growing up. Don't put them down or show disdain. The latest research suggests that adults who expect teens to make good decisions, understand consequences, delay gratification, squelch impulses, and exhibit advanced organizational skills may be asking too much of them. Knowing this can help librarians be more at ease with adolescents.

Teens' brain spurts provide librarians with an opportunity to turn young adults into lifelong readers and library users. During adolescence, the brain develops more plasticity, as some connections between brain cells become activated, while others that are not used atrophy. It's a crucial "use it or lose it" scenario. As Giedd explains: "If a teen is doing music or sports or academics, those are the cells and connections that will be hard-wired. If they're lying on the couch or playing video games or watching MTV, those are the cells and connections that are going to survive."