Motives for Cannabis Use and Risky Decision Making Influence Cannabis Use Trajectories in Teens.

The current study will examine the interactive effects of motives for cannabis use (i.e., health or recreational) and risky decision making (DM) on cannabis use trajectories among adolescents. Data from 171 adolescents, aged 14-17 at the initial visit (baseline), were prospectively analyzed across five time points approximately six months apart. Latent growth curve modeling and linear regression analyses were used. We found a significant interactive effect of "recreational motives" and risky DM on the rate of cannabis use over time. Specifically, among those less likely to use cannabis for recreational purposes, riskier DM was associated with a faster increase in the rate of use over time relative to those with lower risky DM. Additionally, a significant main effect showed that those with a greater proclivity to use cannabis for health purposes had higher initial levels of use at baseline and faster increases in the rate of use over time. Regardless of risky DM, using cannabis for health purposes is associated with faster increases in cannabis use escalation. Additionally, risky DM does impact the association between recreational motives for use and cannabis use trajectories. Future work should examine these associations with additional motives for cannabis use that have been previously validated within the literature.

Cannabis use and episodic memory performance among adolescents: Moderating effects of depression symptoms and sex.

OBJECTIVE: Cannabis use has been linked to poorer episodic memory. However, little is known about whether depression and sex may interact as potential moderators of this association, particularly among adolescents. The current study addresses this by examining interactions between depression symptoms and sex on the association between cannabis use and episodic memory in a large sample of adolescents. METHOD: Cross-sectional data from 360 adolescents (M age = 17.38, SD = .75) were analyzed at the final assessment wave of a two-year longitudinal study. We used the Drug Use History Questionnaire to assess for lifetime cannabis use, and the Computerized Diagnostic Interview Schedule for Children, Fourth edition to assess the number of depression symptoms in the past year. Subtests from the Wechsler Memory Scale, Fourth Edition and the California Verbal Learning Test, Second Edition were used to assess episodic memory performance. RESULTS: The effect of the three-way interaction among cannabis use, depression symptoms, and sex did not have a significant impact on episodic memory performance. However, follow-up analyses revealed a significant effect of the two-way interaction of cannabis use and depression symptoms on episodic memory, such that associations between cannabis use and episodic memory were only significant at lower and average levels of depression symptoms. CONCLUSIONS: Contrary to our hypotheses, we found that as depression symptoms increased, the negative association between cannabis use and episodic memory diminished. Given the use of a predominantly subsyndromic sample, future studies should attempt to replicate findings among individuals with more severe depression.

ARCHIE++ : A Cloud-Enabled Framework for Conducting AR System Testing in the Wild.

In this paper, we present ARCHIE++, a testing framework for conducting AR system testing and collecting user feedback in the wild. Our system addresses challenges in AR testing practices by aggregating usability feedback data (collected in situ) with system performance data from that same time period. These data packets can then be leveraged to identify edge cases encountered by testers during unconstrained usage scenarios. We begin by presenting a set of current trends in performing human testing of AR systems, identified by reviewing a selection of recent work from leading conferences in mixed reality, human factors, and mobile and pervasive systems. From the trends, we identify a set of challenges to be faced when attempting to adopt these practices to testing in the wild. These challenges are used to inform the design of our framework, which provides a cloud-enabled and device-agnostic way for AR systems developers to improve their knowledge of environmental conditions and to support scalability and reproducibility when testing in the wild. We then present a series of case studies demonstrating how ARCHIE++ can be used to support a range of AR testing scenarios, and demonstrate the limited overhead of the framework through a series of evaluations. We close with additional discussion on the design and utility of ARCHIE++ under various edge conditions.

Sex differences in bidirectional associations between conduct problems and cannabis use across two years of adolescence.

BACKGROUND: There is a large body of research that has identified bidirectional associations between conduct problems and cannabis use. Despite growing knowledge regarding comorbidities between conduct problems and cannabis use, it remains unclear whether these findings generalize across both males and females. The current study examined sex differences in longitudinal associations between conduct problems and cannabis use in a predominantly Hispanic sample of adolescents followed over a two-year period. METHODS: Participants were 401 adolescents (89.8% Hispanic, 46% female; Mage = 15.5) taking part in a two-year longitudinal investigation examining the associations between neurocognitive functioning and cannabis use. The sample consisted predominantly of youth selected for risk of cannabis escalation, with 90% reporting using cannabis, nicotine, or alcohol prior to baseline. Negative binomial cross-lagged regressions and simple slope difference tests were used for all analyses. RESULTS: We found support for bidirectional associations between conduct problems and cannabis use, controlling for demographics, covariates, and baseline frequencies. Simple slope difference tests revealed that there was a significant, positive association between baseline cannabis use and subsequent conduct problems among females but not males. In contrast, the association between baseline conduct problems and subsequent frequency of cannabis use did not differ as a function of sex. CONCLUSIONS: Our results underscore the importance of viewing cannabis use as a risk factor for maladjustment rather than solely as a consequence, particularly among female adolescents. Information gained from temporal sequencing of cannabis use and conduct problem symptoms can guide the selection of intervention programs for referred youth.