Lisa Freund, a developmental psychologist and neuroscientist at NIH. “The problem is that the incentive/reward system matures earlier than the cognitive control The ability to use reason to control impulses and emotions. The adolescent brain can be somewhat like a rider on a racehorse with no reins. These still-developing brain areas govern judgment, decision-making and impulse control. Although the 18th birthday means legal adulthood, important regions of the brain are still under construction until about age 25. They’ve found something they didn’t expect. NIH-funded scientists have been using advanced imaging tools to take a good look at how the adolescent brain functions. Why does adolescence feel so complicated and intense? It all begins with the brain. Learning about teenage development and behaviors can help parents nurture their children’s strengths and shepherd them over the rough spots. Yet it can also be thrilling to watch kids grow and change. Adolescence can be a bewildering time-for both teens and their parents.