WEDNESDAY, Aug. 8 (HealthDay News) -- Teenagers with less activity in certain areas of the brain are at greater risk for becoming problem drinkers, according to a small new study that also provides evidence that heavy drinking harms young people's developing brains.
Researchers from the University of California, San Diego, performed special MRI scans to examine the brain activity of 40 healthy young people ranging in age from 12 to 16 years. At the time the study began, the teens did not drink alcohol. Three years later, when the teens' brains were scanned again, half of the teens had already started drinking fairly heavily, the researchers noted.
The study revealed that the young people whose brains initially showed less activity in certain areas were more likely to become heavy drinkers over the course of the study. Heavy drinking consisted of four or more drinks on occasion for girls and five or more drinks for boys.
The researchers said that once the teens started drinking, their brain activity increased during memory tests and their brains resembled those of heavy drinkers.
"That's the opposite of what you'd expect, because their brains should be getting more efficient as they get older," said the study's lead researcher, Lindsay Squeglia, in a university news release. "It's interesting because it suggests there might be some preexisting vulnerability."
The study's authors said their findings could shed light on the biological origins of problem drinking among kids. They noted the study should also serve as a reminder that drinking could negatively affect developing young brains.
"You're learning to drive, you're getting ready for college. This is a really important time of your life for cognitive development," said Squeglia. She added that teens with certain disorders, such as depression or ADHD, may be more vulnerable to the adverse effects of heavy drinking.
The study, which did not prove a cause-and-effect relationship between lower brain activity and problem drinking, is published in the September issue of the Journal of Studies on Alcohol and Drugs.
The U.S. Centers for Disease Control and Prevention provides more information on underage drinking.
SOURCE: University of California, San Diego, news release, Aug. 8, 2012
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