Adolescents at risk for drug abuse: a 3-year dual-process analysis

Abstract

Aims: To test longitudinal additive and synergistic dual-process models in youth at documented risk for drug use. The specific dual-process approach examined suggests that engaging in drug use behaviors results from a dynamic interplay between automatically activated associative memory processes and executive reflective/control processes.

Design: This 3-year, three-wave population-based prospective study used mobile computer-based assessments.

Setting: Self-directed computer assessments were completed in school settings in the Los Angeles metropolitan area, California, USA.

Participants: Seven hundred and twenty-five at-risk adolescents (44% female) in continuation high schools were recruited during 9th grade (age at recruitment, 14-16).

Measurements: Key outcome measures included past year alcohol, marijuana and cigarette use at each assessment. Predictors included working memory capacity (WMC), associative memory, the interaction term WMC by associative memory, sex, age, ethnicity and acculturation.

Findings: A significant cross-sectional interaction revealed tobacco-relevant associations were weaker predictors of cigarette use among males with higher WMC than among those with lower WMC (P < 0.004). Alternatively, drug-relevant associations were stronger predictors of past year alcohol (P < 0.001) and marijuana use (P = 0.02) among females with higher WMC than among those with lower WMC. Longitudinal analyses revealed no significant interactions after adjusting for predictive effects of previous drug use. With respect to WMC, females with higher WMC were less likely to use marijuana at 2-year follow-up (P = 0.03). First-order effects of drug-related associations predicted greater alcohol and marijuana use prospectively in males at 1- and 2-year follow up (P ≤ 0.03), and greater past year alcohol and marijuana use in females at 1-year follow up (P ≤ 0.03).

Conclusions: Drug-relevant memory associations play a key role in drug use behavior in at-risk youth.

Keywords: Adolescents; drug use; dual-processes; habit; implicit associations; longitudinal; working memory.

Figure 1

Figure depicts the conceptual model of the latent variable models tested. WAT= spontaneous drug-relevant memory associations assessed with indirect tests of word association; WMC= Working Memory Capacity assessed with the Operation Span Task; xz= WAT by WMC interaction term. Prospective models tested (Wave 2 and Wave 3) controlled for baseline drug use outcomes (past year cigarette, alcohol and marijuana use).

Figure 2

Figure depicts the nature of the interaction of spontaneous memory associations (WAT) and working memory capacity (WMC) on cigarette use in adolescent males. Notes on simple curves: Low WMC = working memory capacity at the mean minus one standard deviation, and High WMC = working memory capacity at the mean plus one SD. Past year cigarette use was assessed on a rating scale with frequency options ranging from 1 (none) to 11 (91 or more times). Scale represents standardized coefficients.