Inside the Teenage Brain

Over-the-top teens like lazy A.J. Soprano and "Desperate Housewives" angst-ridden Andrew and impulsive Danielle reflect our culture's convictions that teens are angry, oversexed risk-takers.

So 17-year-old Ali Nepola, who's at the top of her class, cross-country team captain, a competitive dancer, and popular and well behaved to boot, doesn't quite fit the stereotype. According to new research, Ali's self-control may be the key to her success.

"She's got a lot of self-control and knows her limitations and knows her strengths and weaknesses," says Cathy Nepola, Ali's mom.

Grazyna Kochanska, a professor at the University of Iowa, has tracked Ali and more than 300 other kids for almost 20 years to gauge how their ability to delay gratification and exert self-control affects their lives.

"Self-control is generally considered a very good thing," Kochanska says. "In our own research, this capacity has clearly been associated with positive aspects of social development."

Using a variety of measures, Kochanska and her team test children on how well they can control their impulses. Some tests involve letting a child see a particular reward -- a wrapped present, a piece of candy, an attractive toy -- but not allowing him to touch the item until given permission. Others involve building a tall structure with blocks, then asking the child to wait a specified time before allowing him to knock it down.

Videotaped at 3 years old, Ali is told she can eat the candy placed in front of her but only after the researcher rings a bell. On the video, Ali hops around a bit but does not touch the candy.

In another test, Ali waits more than three minutes -- an eternity to a 3-year-old -- to unwrap a present left just within her reach. Kochanska says this ability to delay gratification will benefit Ali throughout her life.

"Those who have good self-control are more compliant, more cooperative, have good harmonious relationships with their parents, good relationships with their peers, and they have good academic success," Kochanska says.

Pedal to the Floor, No Brakes

But watch almost any teen movie, and you may wonder why impulse control seems to skid off the road during the scary teen years. Experts now know this is because the brain is not fully developed at adolescence.

"If we were to compare the teenage brain to an automobile, it's as if the gas pedal is to the floor, and there are no brakes," says David Walsh, author of "Why Do They Act That Way: A Survival Guide to the Adolescent Brain for You and Your Teen."

Thanks to magnetic resonance imaging, or MRI, technology, we know that the teen brain develops from back to front. In other words, the part of the brain that helps teens reason, plan ahead and manage impulses -- the prefrontal cortex -- is one of the last areas to mature, at around age 25. Until then parents may have a hard time engaging their teens.

"If parents create a supportive, loving, well-organized, predictable environment in the home, I think those children will be all right," Kochanska says.

And that's just the sort of environment Ali's parents provided for her.

"Pretty much been the way that she's been raised is that you don't always get what you want when you want it," says Cathy Nepola. "You just have to wait sometimes, and sometimes when you wait, it's even better."

Learning to delay gratification and exercise self-control are lessons Ali will take with her into her adult years.

"I'd be more comfortable doing the right thing than doing something that I think would be fun, but I'd feel bad about later," Ali says.

Is There Any Difference Between Boys and Girls?

For the first year or two of life, controlling impulses is very tough for kids, which is why the toddler years can be such a challenge.

Toddlers are active and want to explore their environment and can't help reaching or screaming for something they see that's inviting.

But even at that young age, parents can help a child develop better impulse control by making him wait to take turns; by not rushing in to help the minute he whimpers for something; by using routines to create a predictable schedule at home. The goal is to teach your child to tolerate frustration.

Lots of research shows that girls tend to have more impulse control than boys. During the teen years, girls tend to be more emotional, while boys tend to be bigger risk-takers.

Knowing that teens sometimes can't help the way they feel and act -- that they're not misbehaving just to be annoying or worse -- can go a long way toward defusing battles.

If your teen is more like an A.J. than an Ali, what can you do?

Encourage your teen's involvement in any activity that requires practice, whether it's sports or music lessons, volunteer work or a job that forces your child to set goals.

The most important thing is for parents to model patience. We live in a get-it-now environment where everything is about instant gratification, so showing teens how you set goals to achieve what you want, as opposed to lecturing about it, is critical.