The case of the teen brain.

• Position: STUDENT WORKSHEET

Assignment: Study the article to learn more about the teen brain. Then complete the questions below.

* Investigator:

Dr. James Bjork, Scientist, National Institute on Drug Abuse, National Institutes of Health

* Mystery:

"I've always been interested in what it is about the brains of some people that causes them to do something that could irreversibly change their life," says Dr. Bjork. He started studying impulsive behavior in adults, but found that many highly destructive behaviors, such as drug abuse, start in adolescence. He wanted to find out if unique features exist in the teen brain that make this kind of impulsive behavior more likely.

* Uncovering Clues:

Dr. Bjork studied how people's brains respond to environmental challenges when they are making decisions.

Experiment Design: Dr. Bjork asked adults and adolescents to play a game that involved a conflict between being able to win a guaranteed reward or risking it all for the opportunity to win more.

Data Collection: As the participants played the game, Dr. Bjork studied their brain activity using functional Magnetic Resonance Imaging (fMRI). This specialized brain scan allowed him to see which areas of the brain were engaged (or activated) when the participants made decisions about what risks to take in the game.

Data Analysis: Dr. Bjork's research showed that while the game was being played, the middle frontal cortex was much more engaged/active in adults than in teens.

"I had to present adolescents with a very clear and severe threat of monetary loss [in the game] to start getting that area of the brain to become active," says Dr. Bjork. These findings are supported by other research that shows that the brain continues to mature through a person's 20s, and that the frontal cortex of the brain is one of the last sections to fully mature.

* Drawing Conclusions:

Dr. Bjork's findings may help us understand why adolescence is a time of heightened risk-taking behavior. His experiment shows that a part of the cortex that helps us weigh risks and rewards is less active in teens, and this may affect how they make decisions. By being less sensitive to risk and more impulsive, teens could make unwise decisions about drugs, especially when the consequences of drug use are not always immediate or clear. Not all risk-taking, however, is bad for one's health. Teens' spirit for adventure means they can be more open to positive risks, such as taking up the challenge of learning a new skill, making...