Peers Increase Teen Driving Risk via Heightened Reward Activity

New research on the adolescent brain provides support for laws, existing in some locales, that prohibit teen drivers from having peers as passengers. Drs. Laurence Steinberg and Jason Chein at Temple University in Philadelphia offered adolescents, young adults, and adults monetary rewards for “driving” around a computer-simulated track. In the simulation, traffic lights appearing at frequent intervals turned yellow as the cars approached, forcing risk-reward choices. The driver might save time by proceeding through, but doing so would risk a collision and cause more delay than stopping and waiting for green.

The adolescents, but not the older participants, chose the risky option significantly more often when they knew two of their friends were watching. Functional magnetic resonance imaging demonstrated that the friends’ presence heightened activity in the teens’ ventral striatum and orbitofrontal cortex—brain regions that predict and assess the value of reward. This social effect was especially pronounced when the teens made risky decisions to proceed through the yellow light. As the friends did not say anything to influence the drivers’ behaviors, the researchers concluded that the presence of peers is sufficient in itself to make risks feel more worthwhile to teens.
Developmental Science 14(2):F1–F10, 2011. Abstract Available