Your Brain as a Teen

NPR:

Teens can’t control impulses and make rapid, smart decisions like adults can — but why?

Research into how the human brain develops helps explain. In a teenager, the frontal lobe of the brain, which controls decision-making, is built but not fully insulated — so signals move slowly.

“Teenagers are not as readily able to access their frontal lobe to say, ‘Oh, I better not do this,’ ” Dr. Frances Jensen tells Fresh Air‘s Terry Gross….

“We have a natural insulation … called myelin,” she says. “It’s a fat, and it takes time. Cells have to build myelin, and they grow it around the outside of these tracks, and that takes years.”

This insulation process starts in the back of the brain and heads toward the front. Brains aren’t fully mature until people are in their early 20s, possibly late 20s and maybe even beyond, Jensen says.