Why are some youth more prone to engage in substance use than others? Applying the dual systems model to a high-risk population
Adolescence is a life stage defined by significant biological and social changes. Youth with underlying risk for substance use involvement may experience difficulty navigating these changes, increasing the likelihood of maladjustment.
High-risk youth such as those who have a parent with a substance use disorder are at increased risk for engaging in heavier substance use during adolescence compared to low-risk who do not have a parent with a substance use disorder. Crucially, understanding developmental processes that lead to substance use are important to know in order to guide prevention efforts. This study aimed at examining the role of impulse control and reward-seeking in the development of substance use in high-risk youth interpreted through the lens of the dual systems model.
The dual systems model assumes that substance use emerges during adolescence as the result of the normal developmental process. This development is characterized by the early maturation of reward-seeking and later increase in impulse control. Reward seeking includes sensation-seeking behaviors (e.g., mountain climbing) and accelerates in development, reaching its peak around 15 years old. Counter to sensation seeking, impulse control (e.g., planning ahead) develops gradually, not reaching full maturation until adulthood. Due to these differences, adolescence is a unique stage when impulse control is not developed well enough yet to manage the rise in reward-seeking tendencies. The maturational difference between impulse control and sensation-seeking is thought to be partly responsible for adolescent risk-taking behaviors, such as substance use.
Many youths experience healthy development, though high-risk youth who have a parent with a substance use disorder may have trouble adjusting to the changes that occur during adolescence. Attributable to genetic and environmental risk factors, high-risk youth tend to have poorer impulse control than low-risk youth and are prone to display trait-like impulsive behavior. The poor impulse control of youth who have a parent with a substance use disorder may be particularly relevant during adolescence due to the processes implicated in the dual systems model.
The present study was designed to collect evidence for the relative changes in impulse control and sensation-seeking, as well as the relation of these with substance use among high- and low-risk youth. High-risk youth were expected to have even more difficulty regulating the adolescent rise in sensation-seeking compared to low-risk youth, because the maturational difference between impulse control and sensation-seeking may be exaggerated. To examine this possibility, we tested impulse control and sensation-seeking at six-month intervals between the ages of 13–16 years among high- and low-risk youth. Our main findings are highlighted below:
- Overall, high-risk youth had poorer impulse control than low-risk youth, a difference that was stable during adolescence. In turn, poorer impulse control was related to heightened sensation seeking. Put differently, while there was not a direct difference in sensation seeking between high- and low-risk youth, there was an indirect difference due to the poorer impulse control observed among high-risk youth.
- Compared to low-risk youth, high-risk youth were more likely to engage in substance use because of the relationship between poor impulse control and heightened sensation seeking.
- We also found a developmental relationship between impulse control and sensation-seeking, though it was independent of whether or not youth had a parent with a substance use disorder. Specifically, we found that those youth with slower gains in impulse control were likely to experience even faster development in sensation-seeking than what is typical.
Our findings reflect a stable and developmental relationship between impulse control and sensation-seeking. The higher rates of substance use among high-risk youth co-occurred with this lower ability to regulate the adolescent rise in sensation seeking. These results refine the dual systems model; suggesting a pathway approach where poor impulse control is related to heightened sensation seeking that in turn is related to substance use. This differs from the traditional approach to the dual systems model focusing on poor impulse control exacerbating the negative consequences of the adolescent rise in sensation seeking.
How might these results of the study inform prevention efforts? We suggest that prevention efforts should take advantage of the maturational timing of sensation seeking. That is, youth may benefit from prevention efforts that shift reward-seeking tendencies away from unhealthy behaviors like substance use to healthy behaviors like academic achievement, playing sports, or performing in a play. After all, adolescence is a time when exploration should be encouraged!
Please read the full article here.
Alexander Wasserman is a T32 Postdoctoral Fellow in the Neurobehavioral Research Laboratory and Clinic (NRLC) at the University of Texas Health Science Center at San Antonio (UTHSCSA). His research interests include adolescent risk behavior, the development of cognitive control and reward sensitivity, and applications of advanced quantitative methods.