April 30, 2012
Brain Activity May Be Partially Responsible For Drug Use In Teens
A new imaging study has reportedly discovered a link between diminished activity in part of the brain with the likelihood that a teenager will start smoking, drinking, or abusing drugs.
The research, said to be the largest imaging study of the human brain ever conducted, was completed by an international team of scientists including Robert Whelan and Hugh Garavan of the University of Vermont. The researchers looked at nearly 1,900 14-year-old participants, and discovered that many of the teenagers were at risk of experimenting with illicit substances because of differences in their brain.
One of the key findings of the study, according to a university press release, is diminished activity in a network that involved the orbitofrontal cortex (OFC), a prefrontal cortex region in the frontal lobes of the brain which has been found to be involved in the cognitive processing of decision-making.
Some of the networks "are not working as well for some kids as for others," Whelan said, which in turn makes them more impulsive and more likely to choose to partake of smoking, drinking, or drug use when given the chance. Garavan added that testing for lower function in this and related cognitive networks could potentially be used by researchers as "a risk factor or biomarker for potential drug use."
In addition, the research team was able to show that other, newly discovered brain networks have a correlation with the symptoms of attention-deficit hyperactivity disorder (ADHD).
While the University of Vermont news release says that there has been speculation between ADHD and the potential for drug use, as both are said to be issues that plague impulsive individuals, the Whelan/Garavan team discovered that they are actually controlled by different networks within the brain.
"This strengthens the idea that risk of ADHD is not necessarily a full-blown risk for drug use as some recent studies suggest," the university said. "The impulsivity networks -- connected areas of activity in the brain revealed by increased blood flow -- begin to paint a more nuanced portrait of the neurobiology underlying the patchwork of attributes and behaviors that psychologists call impulsivity -- as well as the capacity to put brakes on these impulses, a set of skills sometimes called inhibitory control."
Their findings were published online Sunday in the journal Nature Neuroscience.