Teenage deaths in the industrialized world are often caused by impulsive, risky behaviors associated with alcohol and drug use. Robert Whelan and Hugh Garavan of the University of Vermont, and colleagues, conducted an imaging study of the brain of 1,896 14-year-olds, wherein they discovered that differences in brain networks precede drug and alcohol use. Network inactivity in the orbitofrontal cortex is associated with experimentation with alcohol, cigarettes and illegal drugs in early adolescence while network inactivity in another area is associated with attention-deficit hyperactivity disorder (ADHD). Both ADHD and early drug use are associated with poor inhibitory control, the capacity to put brakes on impulses in the brain. According to Garavan, “understanding brain networks that put some teenagers at higher risk ... could have large implications for public health.”