Researchers and clinicians know that youths with a family history of alcohol and other drug use disorders (FH+) have a greater risk of developing substance-use disorders (SUDs) than their peers with no such family histories. This increased risk may be related to impaired maturation of forebrain circuitry. A new study examines forebrain activity in youths with a family history of SUDs, finding they had greater activity in several forebrain regions during a specially designed task than their peers with no such family histories, indicating their forebrain regions function less efficiently.
Results will be published in the December 2014 online-only issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.
“The forebrain is important for several major cognitive processes, including decision-making and impulse control, and activity in several forebrain regions increases when people perform tasks that involve those processes,” explained Ashley Acheson, an assistant professor at The University of Texas Health Science Center at San Antonio as well as corresponding author for the study. “Not surprisingly, dysfunctions in the forebrain are involved in many psychiatric disorders, including alcohol and other drug use disorders. FH+ youths and young adults often have impairments in cognitive processes controlled by the forebrain such as decision-making and impulse control, and we think those cognitive impairments may contribute to their increased risk for developing alcohol and other drug problems.”
“The term forebrain encompasses large areas of the cerebral cortex that collectively do three things,” added William R. Lovallo, professor of psychiatry and behavioral sciences at the University of Oklahoma Health Sciences Center. “The forebrain classifies and identifies events in the environment. It develops a response strategy to the classification step. Finally, it starts the motor process of actually making the motor response.”
“We looked at brain activity when kids did a computer task requiring them to quickly respond to some cues but not to others,” said Acheson. “Previous studies have focused on how FH+ kids’ brain activity looked during the parts of the task when they weren’t supposed to respond to cues to see how inhibition circuitry was affected. We looked at brain activity in all parts of the task compared to the rest to see if there were more general differences in brain functioning.”
“This study used a task that is especially sensitive to a person’s ability to inhibit a response when that response is the one most likely to occur,” explained Lovallo. “In the Go/NoGo paradigm, persons have a tendency to respond with a button press when a signal appears on their screen and stopping that requires significant cognitive processing. So, we usually think of the Go/NoGo tasks as being sensitive to impulsive tendencies. Persons who are impulsive are likely to perform worse than less impulsive persons. This is of interest in alcoholism research because of data and theories that view impulsive and less-inhibited persons as being at higher risk of misusing alcohol and recreational drugs.”
University of Texas Health Science Center at San Antonio
University of Oklahoma Health Sciences Center