U.S. researchers believe magnetic resonance imaging, or MRI, increasingly is showing promise as a technique to predict adolescent vulnerability to substance abuse disorders.

As underage alcohol and drug use is increasingly being recognized as a public health and social problem in the United States, with long-term consequences that include poorer academic performance, neurocognitive deficits and psychosocial problems, such study may help identify youth at the highest risk for these problems and allow prevention approaches.

Youth who begin drinking before age 15 have four to six times the rate of lifetime alcohol dependence than those who do not drink by age 21, researchers noted in an analysis published in Current Opinion in Behavioral Sciences.

"Structural and neural alterations in the brain from drug and alcohol abuse have now been well established," said Anita Cservenka, an assistant professor in the College of Liberal Arts at Oregon State University (OSU), and co-author of the study. "It's also becoming clear that some of these alterations can exist before any substance abuse, and often are found in youth who have a family history of alcohol and drug use disorders. These familial risk factors can play a role in future substance abuse, along with environmental risk factors such as peer influence, personality and psychosocial interactions."

Neuroimaging studies show significant overlap in brain scans between those with a family history of alcohol- and substance-use disorders and youth who begin using substances during adolescence.

A factor contributing to a peak in substance use during adolescence, researchers say, may be emotion and reward systems that develop before cognitive control systems, leaving youth more vulnerable to risk-taking behaviors. Almost two thirds of 18-year-olds, for instance, support lifetime alcohol use; 45 percent marijuana use; and 31 percent smoking cigarettes.

"We're just beginning to understand the risk factors for substance abuse and the consequences of adolescent substance use with these types of large, long-term studies," Cservenka was quoted as saying in a news release from OSU. "Ultimately such information should help inform us about who might be at most risk and what brain areas are most vulnerable, so we can target them and work to prevent the problems."

If an MRI showed weakness in working memory, for instance, computer games or behavioral tasks might help strengthen the area of the brain that is deficient. Similar approaches might also be used to help address issues such as stress and depression, she said.

source: Xinhua