Teen Brains Develop Ability to Avoid Risky Behavior It might help them ward off peer pressure By Nick McMaster, Newser Staff Posted Mar 10, 2011 6:04 PM CST 6 comments Comments Listen to your ventral striatum, kids. (AP Photo/Paul Sakuma) (Newser) – Looks like teens have a built-in defense mechanism against peer pressure: New research shows that the part of the brain involved in decision-making develops significantly in the early teen years, the Telegraph reports. Researchers from the University of Oregon found that activity in the ventral striatum, a part of the pre-frontal cortex tasked specifically with whether to take risks, increases dramatically between ages 10 and 13. "People tend to think of adolescence as the time when teenagers are really susceptible to peer pressure," said an Oregon psychology professor. "That is the case, but in addition to that added susceptibility they are also improving their ability to resist it."