Biomarker of Future Alcohol Abuse Risk in Teens?
Neuroscientists with the Adolescent Development Study are finding differences in the brains of adolescents at high risk for alcohol use disorders, which could aid in the development of prevention strategies.
“The primary goal of the Adolescent Development Study is to look at what’s happening in the brains of adolescents before they have started drinking and doing drugs,” study co-director John VanMeter, PhD, from Georgetown University Medical Center in Washington, DC, told Medscape Medical News.
“We know from lots of studies that if you look at teenagers who have started drinking and doing drugs that there are certain deficits in their brain, mainly in the prefrontal cortex. But the question is open as to whether some of these deficits predate the alcohol and drug use or are strictly a consequence,” Dr VanMeter explained.
The findings were presented at the Society for Neuroscience 2014 Annual Meeting.
Biomarkers of Alcohol Abuse Risk
Researchers working in Dr VanMeter’s laboratory, led by Tomas Clarke and Stuart Washington, PhD, used functional MRI (fMRI) to assess connectivity within the executive control network (ECN) of 16 adolescents at medium or high risk and 16 at low risk for future alcohol abuse on the basis of responses to the Drug Use Screening Inventory. Their average age was 12.6 years. They had never used alcohol.
The researchers observed that overall connectivity in the ECN — which includes areas that process emotion, impulsivity, and self-control — was significantly lower in adolescents at medium/high risk for alcohol misuse than in their peers at low risk.
The medium/high-risk group also had higher scores on the Behavior Rating Inventory of Executive Function, indicating increased difficulty with executive functioning.
“The clinical implications of our findings are that low ECN connectivity is a potential biomarker for risky behavior, particularly and especially earlier alcohol use,” Dr Washington said.
Related findings from the Adolescent Development Study team presented at the meeting hint that functional connectivity between the insula and anterior cingulate predicts impulsivity in adolescents at risk for alcohol abuse.
The researchers studied 17 adolescents at medium/high risk and 17 at low risk for alcohol misuse. They were 11 to 13 years old and had never used alcohol or drugs.
During fMRI, the adolescents took the Continuous Performance Task, which measures impulsivity. Compared with the low-risk group, the medium/high-risk group had reduced connectivity in the prefrontal and insular cortex, the researchers reported, and this predicted higher levels of impulsivity.
“The finding that adolescents at risk for alcohol use exhibit altered functional connectivity between the insula and anterior cingulate in relation to inhibitory control in itself is significant, but what’s more important is these adolescents were alcohol naive,” Benson Stevens, PhD candidate, Interdisciplinary Program in Neuroscience at Georgetown University, who worked on the study, told Medscape Medical News.
“This suggests those at risk have baseline differences in inhibitory control, which is not confounded by prior alcohol use. This could have clinical importance as it could help inform early interventions aimed at helping adolescents at risk for alcohol misuse by explicitly incorporating methods that could improve inhibitory control and strengthen brain function underlying it,” Stevens added.
The Adolescent Development Study is funded by the National Institutes of Health. The authors have disclosed no relevant financial relationships.
Society for Neuroscience 2014 Annual Meeting. Posters 122.19 and 122.20. Presented November 16, 2014.
Published Nov 18, 2014 http://www.medscape.com/viewarticle/835086
Written by Megan Brooks