"Heightened sensitivity to anticipated rewards motivates adolescents to engage in risky acts, such as unprotected sex, fast driving or drugs when the potential for pleasure is high," Laurence Steinberg, a professor of psychology at Temple University, said in a statement. "This hypersensitivity to reward is particularly pronounced when they're with their friends."
In other words, adolescents mature intellectually before they mature socially or emotionally, a fact that helps explain why teenagers who are so smart in some respects sometimes do surprisingly dumb things, Steinberg said.
From adolescence into early adulthood, there is a strengthening of activity in brain systems involving self-regulation, and functional magnetic resonance imaging showed reward centers in the adolescent brain are activated more than in children or adults, he said.
Steinberg said important changes in adolescent brain anatomy and activity take place far later in development than previously thought, and the findings could impact how policymakers and the highest courts treat teenagers.
The findings were presented at the American Psychological Association's 120th annual convention in Orlando, Fla.