Why do some teenagers start smoking or experimenting with drugs—while others don't? In the largest imaging study of the human brain ever conducted—involving 1,896 14-year-olds—scientists have discovered a number of previously unknown networks that go a long way toward an answer. Dr. Robert Whelan and Dr. Hugh Garavan of the University of Vermont, along with a large group of international colleagues, report that differences in these networks provide strong evidence that some teenagers are at higher risk for drug and alcohol experimentation—simply because their brains work differently, making them more impulsive. Their findings were published online on April 29, 2012 in Nature Neuroscience. This discovery helps answer a long-standing chicken-or-egg question about whether certain brain patterns come before drug use—or are caused by it. "The differences in these networks seem to precede drug use," says Dr. Garavan, Dr. Whelan's colleague in the University of Vermont’s psychiatry department, who also served as the principal investigator of the Irish component of a large European research project, called IMAGEN, that gathered the data about the teens in the new study. In a key finding, diminished activity in a network involving the "orbitofrontal cortex" is associated with experimentation with alcohol, cigarettes, and illegal drugs in early adolescence. (Referential web site: 60-day treatment http://www.rehabs.com/about/60-days-two-months-program/) "These networks are not working as well for some kids as for others," says Dr. Whelan, making them more impulsive. Faced with a choice about smoking or drinking, the 14-year-old with a less functional impulse-regulating network will be more likely to say, "yeah, gimme, gimme, gimme!" says Dr.Login Or Register To Read Full Story