Brooks King-Casas awarded grant for research into the neurobehavioral determinants of adolescent risk-taking

Brooks King-Casas, Ph.D.

Brooks King-Casas, Ph.D.

What makes the adolescent brain so susceptible to health risks? Virginia Tech scientists have received a $3.9-million grant over five years from the National Institute on Drug Abuse for research into the neurobehavioral determinants of risky behavior in adolescents.

The co-principal investigators of the grant are Brooks King-Casas, an assistant professor at the Virginia Tech Carilion Research Institute, and Jungmeen Kim-Spoon, an associate professor of psychology at Virginia Tech.

Among youth in the United States, the leading causes of morbidity and mortality include tobacco, alcohol, and other drug use, as well as sexual behaviors that contribute to unintended pregnancy and sexually transmitted diseases, such as HIV infection.

According to the King-Casas, researchers have increasingly focused on the identification of potential neurobiological vulnerabilities. Current hypotheses suggest differing developmental trajectories of two distinct neural systems that regulate risky decisions: early maturation of a reward system in adolescence that biases decisions toward high-reward options, combined with late maturation of an executive control system that biases decisions away from options with potential negative consequences.

The principal goal of the research will be to address the problems of drug addiction and sexually transmitted diseases using developmental neuroscience to inform scientists and practitioners about the role of adolescents’ developing brains in decision-making about risks.

King-Casas and Kim-Spoon will study the outcomes of adolescents’ substance use and risky sexual behaviors, such as multiple sexual partners and unprotected sex, throughout the middle teen years. The researchers will use functional magnetic resonance imaging to identify neural correlates of adolescent decision-making that have been previously related to risky behaviors and the avoidance of these behaviors: reward/risk sensitivity (reward system) and cognitive control (executive system).

“The rapid increases of health risk behaviors in a subgroup of adolescents make identification and intervention a critical public health priority,” said King-Casas. “We need to understand why only a subset of adolescents experience significant increases in vulnerability to making poor decisions that lead to adverse health outcomes such as drug addiction and sexually transmitted diseases.”

There has been much conceptual work in neurobiology of adolescence that proposes the role of developmental imbalance between early emerging reward system and later maturing cognitive control system in promoting adolescent risky behaviors. Despite being a developmental hypothesis, there has been no empirical study examining developing patterns of neural processes that predict initiation and progression of adolescent substance use and risky sexual behaviors. Thus, we will conduct the first longitudinal analyses to examine how individual differences in developmental trajectories of reward/risk sensitivity and cognitive control are related to the development of adolescent health risk behaviors.

“Our design will allow us to test the hypothesis that cognitive control statistically moderates the effects of reward/risk sensitivity on health-risk behaviors,” said King-Casas. “Our design will also allow us to investigate reciprocal interplay between adolescent health risk behaviors and underlying neural processes.”

Collaborating with King-Casas and Kim-Spoon on the study are Pearl Chiu, an assistant professor at the Virginia Tech Carilion Research Institute; Kirby Deater-Deckard, a professor of psychology at Virginia Tech; and Warren Bickel, director of the Addiction Recovery Research Center at the Virginia Tech Carilion Research Institute.