Cannabis demand and use among veterans: A prospective examination

Projected alcohol demand in college students with heavy drinking

Measures of the relative reinforcing value of alcohol (i.e., alcohol demand) are associated with concurrent and future rates of alcohol use. Given that college-age young adults may fail to predict escalation of substance use, the present project explores the novel construct of projected future demand by college students who engage in heavy drinking and whether it can predict future alcohol use. During an initial session, participants completed a standard alcohol purchase task, a projected alcohol purchase task (i.e., "three months from now"), and measures of past-month alcohol consumption and associated risk. During a follow-up session 3 months later, participants completed another standard alcohol purchase task and measures of consumption and risk. We found that college students (n = 40) projected increases in demand for 3 months in the future but did not exhibit subsequent changes in demand. In addition, measures of projected future demand were associated with subsequent alcohol use. However, when baseline alcohol use and risk were included as additional predictors, projected demand was not a unique predictor of future alcohol use. The current study signals the potential of novel measures of projected demand, which when contrasted with measures of current demand, may lend predictive utility on subsequent trajectories of alcohol use.

Human laboratory models of reward in substance use disorder

Human laboratory models in substance use disorder provide a key intermediary step between highly controlled and mechanistically informative non-human preclinical methods and clinical trials conducted in human populations. Much like preclinical models, the variety of human laboratory methods provide insights into specific features of substance use disorder rather than modelling the diverse causes and consequences simultaneously in a single model. This narrative review provides a discussion of popular models of reward used in human laboratory research on substance use disorder with a focus on the specific contributions that each model has towards informing clinical outcomes (forward translation) and analogs within preclinical models (backward translation). Four core areas of human laboratory research are discussed: drug self-administration, subjective effects, behavioral economics, and cognitive and executive function. Discussion of common measures and models used, the features of substance use disorder that these methods are purported to evaluate, unique issues for measure validity and application, and translational links to preclinical models and special considerations for studies wishing to evaluate homology across species is provided.

Examining the effect of cannabis cues on cannabis demand in sleep, driving, and typical drug-use contexts

PURPOSE

Given the expanding legal cannabis market in the U.S., it is vital to understand how context impacts cannabis use. Therefore, we explored the effect of cannabis cues and cannabis-use context on cannabis demand in 79 adults who reported smoking cannabis at least weekly.

METHODS

Participants completed a single laboratory session consisting of four hypothetical marijuana purchase tasks (MPTs) involving either a typical use situation or a driving or sleep context. The MPTs were alternated with exposure to cannabis or neutral picture cues based on block randomization by gender.

RESULTS

Cannabis cues increased self-reported craving for cannabis (p =.044) but did not significantly alter demand (ps =0.093-0.845). In the driving context, participants demonstrated a significant reduction in cannabis demand, indicated by lower intensity (p <0.001), Omax (p <0.001), and Pmax (p <0.001), breakpoint (p =.003), and higher α (p <0.001). The sleep context was associated with significantly greater α (p <0.006) but nonsignificant effects for other indices (ps =0.123-0.707). Finally, cannabis cues increased Omax (p =.013) and breakpoint (p =.035) in the sleep context but not in the typical-use context.

CONCLUSIONS

These findings suggest that cannabis-use behavior is sensitive to contingencies surrounding driving after cannabis use and may also be sensitive to sleep contexts in the presence of cannabis cues. Since this is the first study to examine driving and sleep contexts, we caution against drawing broad conclusions until future research is conducted to replicate these findings.