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Background: Prompted by the ongoing debate regarding whether cannabis serves as a complement to or substitute for alcohol, this study uses prospective data to examine daily associations between medicinal versus recreational cannabis and alcohol use in veterans. Methods: Three semi-annual waves of Timeline Followback Interview data were collected from a sample of veterans who reported co-using alcohol and cannabis on at least one day (N = 115; 56% medicinal users; 93% male; 62,100 observations). Linear mixed effects models were used to examine the association between daily cannabis use and number of drinks consumed across time for both medicinal and recreational users and to examine the frequency medicinal cannabis used to substitute for alcohol. Results: Compared to medicinal users, recreational users were more likely to drink more on cannabis use days relative to non-use days. Among medicinal users, those endorsing more frequent use of cannabis as a substitute for alcohol reported fewer number of drinks consumed on days when cannabis was used relative to non-use days. Conclusions: Among veterans, recreational users are at greater risk for increased drinking when co-using cannabis at the daily level, an association that is stable over time. Medicinal users may be at lower risk for increased drinking on days when cannabis is also used, especially those who endorse using cannabis to substitute for alcohol. Findings help clarify the debate on cannabis-alcohol substitution or complementary associations in a sample of veterans and suggests that alcohol interventions should address cannabis use as a risk factor, especially for recreational users.

Although alcohol use disorders (AUDs) have been associated with impulsive personality traits and reduced working memory capacity (WMC), less is known about the nature of their interrelationships. This study was designed to test the hypothesis that low WMC is associated with both impulsive personality and alcohol problems, and that impulsive personality mediates the association between low WMC and alcohol problems. Measures of impulsive personality, WMC, and alcohol problems were assessed in a sample of young adults (N = 474), that varied widely in severity of alcohol problems, 57% of whom had alcohol dependence. Simple correlations revealed that WMC, impulsive personality traits, and alcohol problems were all significantly related. Structural equation models (SEMs) showed that impulsivity partially mediated the association between WMC and alcohol problems. Although directionality cannot be determined from these cross-sectional data, the results suggest that reduced WMC may promote impulsivity, which in turn, predisposes to alcohol problems. [ABSTRACT FROM AUTHOR]

Alcohol use is prevalent among young adults, with significant rates of binge drinking and frequent reports of both positive and negative consequences. The current study investigates how positive drinking consequences influence subsequent incentives ratings and drinking behavior. Utilizing mobile daily diary data from 104 young adults over two weeks (event N = 507), we assessed the impact of event-specific positive consequences on future incentive ratings and drinking quantity. Findings revealed that positive consequences were not consistently associated with higher sensitivity to incentives, opposing hypotheses. Specifically, positive alcohol consequences were associated with a slight decrease in next-event alcohol incentive ratings, contrary to the expected positive feedback loop (b = -0.13, p = 0.03). While previous event experiences did not significantly moderate the relationship between incentive ratings and drinking quantities, within-subject increases in incentive ratings for social/party (IRR = 0.45, p < 0.001) and alcohol (IRR = 0.39, p < 0.001) incentives were linked to changes in drinking quantity. Results underscore the complexity of the relationship between positive consequences and drinking behavior, indicating that individual differences, experienced consequences, and salient rewards (i.e., incentives) may play crucial roles in future drinking behavior. Future research should explore additional mechanisms of learning and diverse populations to expand on these findings and enhance strategies for reducing risky drinking behaviors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier Ltd. All rights reserved.)

Introduction: Rates of prenatal cannabis use (PCU) have increased in recent years. Despite evidence of developmental health consequences to offspring and birthing person, there has been a reduction in the perception of PCU-related harms. Due to the stigma and risk of legal consequences associated with disclosing PCU, individuals are often cautious to seek information from their healthcare providers. Thus, pregnant people are more likely to seek information from anonymous sources, such as online support forums. Information garnered from these anonymous online forums can shed light on the patterns and motives for cannabis use among this population. These insights can help to better inform prevention efforts aimed at reducing potential harms of PCU and improve intervention efforts., Methods: Posts (N = 120) from an online pro-cannabis pregnancy forum called "Ganja Mamas" on WhattoExpect.com were randomly selected and analyzed if they covered topics related to PCU. A qualitative coding structure based on the existing PCU literature was created and refined to include other emergent topics. The coding structure was used to apply thematic analysis to posts; associated codes were grouped into themes. Codes specific to symptom management for physical and mental health were subsequently subjected to further conceptual analysis for the current study., Results: Four themes related to symptom management during pregnancy were identified: 1) cannabis use and impacts of use for a variety of mental health symptoms, including depression and anxiety; 2) cannabis use for physical health symptoms and conditions, such as nausea and pain; 3) use of cannabis to achieve homeostasis and manage stress; 4) decision-making about using cannabis for symptom management, such as using cannabis instead of prescription medications. Most discussions in this pro-cannabis forum reflected perceptions that cannabis was effective in treating the conditions for which it was used; however, limitations of cannabis' efficacy were also mentioned., Discussion: There is need for reduced stigma and open communication between pregnant persons who use cannabis and their providers in discussing how to manage their mental and physical health symptoms. Understanding the various symptoms for which individuals use cannabis during pregnancy to self-treat can inform these conversations and the expansion of harm reduction strategies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Gunn, Aston, Artis, Nesi, Pedersen and Micalizzi.)

Research on real-world patterns of substance use increasingly involves intensive longitudinal data (ILD) collection, requiring long assessment windows. The present study extends limited prior research examining event- and person-level influences on compliance and response consistency by investigating how these behaviors are sustained over time in an ILD study of alcohol and cannabis co-use in college students. Participants ( n = 316) completed two 28-day bursts of ILD comprising five daily surveys, which included a morning survey of prior-day drinking. We used linear mixed effects models in a multilevel interrupted time series framework to evaluate the associations of time and measurement burst with (a) noncompliance (count of missed surveys) and (b) response consistency (difference between same-day report of drinking and morning report of prior-day drinking). We observed that time was positively associated with noncompliance, with no discontinuity associated with measurement burst. The slope of time was more positive in the second burst. Neither time nor measurement burst were significantly associated with consistent reporting. However, survey nonresponse and consistency of responding appeared to be impacted by the same-day use of substances. Overall, compliance decreased while consistency was stable across the duration of a lengthy ILD protocol. Shorter assessment windows or adaptive prompting strategies may improve overall study compliance. Further work examining daily burden and context is needed to inform future ILD design. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Background: There is significant conflicting evidence as to how using cannabis while drinking alcohol (ie, simultaneous alcohol and cannabis use) impacts alcohol volume consumed, patterns of drinking, and alcohol-related consequences. The impact of simultaneous use on drinking outcomes may be influenced by several within-person (eg, contextual) and between-person (individual) factors., Objective: This study was designed to examine naturalistic patterns of alcohol and cannabis use to understand how simultaneous use may impact drinking outcomes. The primary aims were to understand the following: (1) if simultaneous use is associated with increased alcohol consumption and riskier patterns of drinking, (2) if simultaneous use leads to increased alcohol consequences, and (3) how contextual circumstances moderate the impact of simultaneous use on consumption and consequences., Methods: Data collection involves a 28-day ambulatory assessment protocol in which a sample of non-treatment-seeking young adults who report simultaneous use of alcohol and cannabis complete ecological momentary assessments (random, event-contingent, and time-contingent surveys) of alcohol and cannabis use, contexts, motives, and consequences on their personal smartphones while continuously wearing an alcohol biosensor bracelet. Participants also complete a baseline assessment, brief internet-based check-in on day 14, and a final session on day 28. Community-based recruitment strategies (eg, social media and flyers) were used to enroll 95 participants to obtain a target sample of 80, accounting for attrition., Results: Recruitment and data collection began in May 2021 and continued through June 2024. Initial results for primary aims are expected in October 2024. As of March 2024, the project had recruited 118 eligible participants, of whom 94 (79.7%) completed the study, exceeding initial projections for the study time frame. Remaining recruitment will provide the capacity to probe cross-level interactions that were not initially statistically powered. Strengths of the project include rigorous data collection, good retention and compliance rates, faster-than-expected enrollment procedures, use of a novel alcohol biosensor, and successful adaptation of recruitment and data collection procedures during the COVID-19 pandemic., Conclusions: This is the first investigation to assess the key momentary predictors and outcomes of simultaneous use as well as self-reported and objective (via alcohol biosensor) measures of alcohol consumption and patterns. The results of this study will inform prevention efforts and studies of individuals who use cannabis who are engaged in alcohol treatment., International Registered Report Identifier (irrid): DERR1-10.2196/58685., (©Rachel L Gunn, Jane Metrik, Nancy P Barnett, Kristina M Jackson, Sharon Lipperman-Kreda, Robert Miranda Jr, Timothy J Trull, Mary Ellen Fernandez. Originally published in JMIR Research Protocols (https://www.researchprotocols.org), 25.09.2024.)

Objective: Pregaming is common among college students and is associated with heavy drinking and negative alcohol-related consequences. The use of cannabis on pregaming days may exacerbate negative alcohol-related consequences, and the ordering of when cannabis is used on these days may buffer against or intensify these consequences. Considering the growing rates of simultaneous use of cannabis and alcohol among college students, it is necessary to examine the role of pregaming behaviors in the context of cannabis use and its effects on alcohol-related consequences., Method: In the present study, college students ( N = 485) completed a baseline survey and 14 days of daily surveys, reporting on daily alcohol and cannabis use and alcohol-related negative consequences. Multilevel structural equation models were fit to evaluate cannabis outcomes on pregaming versus non-pregaming drinking days and ordering effects on alcohol-related consequences, controlling for number of drinks, age, and sex., Results: Across all drinking days, pregaming on that day as well as cannabis use during drinking on that day were associated with a greater risk for alcohol-related consequences. On days that did not involve pregaming, the use of cannabis before drinking was associated with a greater risk for negative alcohol-related consequences, whereas cannabis use after drinking was associated with less risk for consequences. These effects were observed on non-pregaming days only and not on days with pregaming., Conclusions: Findings have implications for brief interventions with students, as analyses suggested that both cannabis use and pregaming--independent of number of drinks consumed--are risky behaviors associated with alcohol-related consequences.

Objective: Pregnant and postpartum people want more and higher quality information about the effects of perinatal cannabis use (PCU) on child health, and they turn to anonymous sources of information, such as online pregnancy forums, to make decisions about its use. This study characterized perceptions of the developmental impact of PCU on children via a narrative evaluation of a public forum on which people discuss a range of issues around cannabis use., Method: A random sample of 10 threads per month from June 2020 to May 2021 were scraped from the "Ganja Mamas" forum on Whattoexpect.com. Posts were analyzed if they discussed use of cannabis during pregnancy or lactation and children. A qualitative coding structure was developed from a literature review on PCU and was refined for inclusion of emergent topics. Posts were evaluated by two coders using applied thematic analysis and were assessed using an open coding process to identify key topics. Associated codes were grouped into themes., Results: Posters (a) discussed the negative and positive impact of PCU on child physical, cognitive, and socioemotional development; (b) garnered information about PCU from sources other than medical providers; and (c) discussed harm-reduction approaches to reduce impacts of PCU on child health., Conclusions: There is a need for stigma-free support around PCU decision-making for people who select into discussion forums designed for communication and support around parental cannabis use. This forum presents a fruitful opportunity for intervention to encourage health-promoting behaviors through the provision of evidence-based information.

Objective: Simultaneous alcohol and cannabis use (i.e., marijuana, [SAM], using alcohol and cannabis so effects overlap) is associated with increased consumption and consequences compared to single-substance use. SAM use prevalence is increasing, yet there is heterogeneity in use patterns among those engaging in SAM use, which may lead to differential consequences., Method: This study drew on daily data to characterize latent profiles of cannabis, alcohol, and SAM use patterns and to test class differences on related consequences after 3 months among college students engaging in SAM use (77.08% White, 51.67% female). Class indicators were 10 person-level substance use variables derived from repeated daily surveys., Results: Results yielded a three-class solution: Heavy Alcohol, Cannabis, and SAM (Heavy Use, n = 105); Heavy Alcohol-Light Cannabis ( n = 75); and Light Alcohol-Heavy Cannabis ( n = 60). There were significant person-level differences between classes on all substance use indicators (e.g., quantity and frequency of alcohol, cannabis, and SAM) but not sex or race/ethnicity. At 3-month follow-up, the Heavy Use class endorsed more SAM consequences than the other classes. The Heavy Use class did not differ on alcohol or cannabis consequences compared to the Heavy Alcohol-Light Cannabis or Light Alcohol-Heavy Cannabis classes, respectively. The Light Alcohol-Heavy Cannabis class endorsed the fewest alcohol consequences. The Heavy Alcohol-Light Cannabis class endorsed the fewest cannabis consequences., Conclusions: Findings highlight distinct patterns of co-use and their association with consequences at follow-up. Heavy alcohol or cannabis use was associated with consequences for that substance, but heavy use of only one substance was not indicative of SAM-specific consequences., Competing Interests: The authors declare no conflicts of interest., (© 2023 Authors et al.)

Objective: This study aimed to assess agreement between self-report and urine toxicology measures assessing use of 2 illicit simulants (methamphetamine and cocaine) during early pregnancy., Methods: This cross-sectional study of 203,053 pregnancies from 169,709 individuals receiving prenatal care at Kaiser Permanente Northern California between January 1, 2011, and December 31, 2019, assessed agreement ( κ , sensitivity, and specificity) between self-reported frequency and urine toxicology measures of methamphetamine and cocaine early in pregnancy., Results: Prenatal use of the illicit stimulants was rare according to toxicology (n = 244 [0.12%]) and self-report measures (n = 294 [0.14%]). Agreement between these measures was low ( κ < 0.20). Of the 498 positive pregnancies, 40 (8.03%) screened positive on both measures, 204 (40.96%) screened positive on toxicology tests only, and 254 (51.00%) screened positive by self-report only. Relative to toxicology tests, sensitivity of any self-reported use was poor with 16.39% (95% confidence interval [CI], 11.75%-21.04%) of pregnancies with a positive toxicology test self-reporting any use in pregnancy. Relative to self-report, sensitivity of toxicology tests was also poor with 13.61% (95% CI, 9.69%-17.52%) of pregnancies who self-reported any use having positive urine toxicology tests. The sensitivity improved slightly at higher frequencies of self-reported use: daily, 17.50% (95% CI, 5.72%-29.29%); weekly, 25.00% (95% CI, 11.58%-38.42%); and monthly or less, 11.06% (95% CI, 6.89%-15.23%). Specificity was high (>99%), reflecting the high negative rate of use., Conclusions: Findings suggest that using self-report and toxicology measures in combination likely provides the most accurate information on methamphetamine and cocaine use in early pregnancy. Findings also highlight the need to provide supportive nonstigmatizing environments in which pregnant individuals feel comfortable disclosing substance use without fear of punishment., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 American Society of Addiction Medicine.)

Global climate change threatens tropical coral reefs, yet local management can influence resilience. While increasing anthropogenic nutrients reduce coral resistance and recovery, it is unknown how the loss, or restoration, of natural nutrient flows affects reef recovery. Here, we test how natural seabird-derived nutrient subsidies, which are threatened by invasive rats, influence the mechanisms and patterns of reef recovery following an extreme marine heatwave using multiyear field experiments, repeated surveys, and Bayesian modeling. Corals transplanted from rat to seabird islands quickly assimilated seabird-derived nutrients, fully acclimating to new nutrient conditions within 3 years. Increased seabird-derived nutrients, in turn, caused a doubling of coral growth rates both within individuals and across entire reefs. Seabirds were also associated with faster recovery time of Acropora coral cover (<4 years) and more dynamic recovery trajectories of entire benthic communities. We conclude that restoring seabird populations and associated nutrient pathways may foster greater coral reef resilience through enhanced growth and recovery rates of corals.

Background: Young adults frequently use alcohol, cannabis, and tobacco together. Given the increased prevalence of e-cigarette use and recreational cannabis use, we investigated daily patterns of alcohol, cannabis, and tobacco use and distinguished combustible tobacco from e-cigarettes., Methods: Young adult college students (N=341) reporting past-month alcohol and cannabis use "at the same time so that their effects overlapped" completed two 28-day bursts of repeated daily surveys. Exposures were day- and person-level use of each substance. Outcomes were (1) same-day co-use of each remaining substance or (2) poly-use of the other substances., Results: Daily use of alcohol, cannabis, combustible cigarettes, and e-cigarettes increased the odds of same-day co-use of the other substances (except combustible tobacco with e-cigarettes) and each poly-use outcome. The influence of person-level substance use on daily substance use was less consistent. Only e-cigarette use increased the odds of daily alcohol use. Use of either tobacco product but not alcohol increased the odds of daily cannabis use. Person-level alcohol and cannabis use increased the odds of daily use of either tobacco product but use of one tobacco product was not associated with daily use of the other product., Conclusions: These findings increase our understanding of emerging daily patterns of alcohol, cannabis, and tobacco co-use, and the impact of different tobacco products. Future work is needed to extend this research into non-college samples and people who use tobacco but do not use alcohol and cannabis simultaneously, and examine daily chronologies of multiple substances that could serve as dynamic markers of risk., Competing Interests: Declaration of Competing Interest There are no interests to declare., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Aims: Alcohol biosensors, including the BACtrack Skyn, provide an objective and passive method of continuously assessing alcohol consumption in the natural environment. Despite the many strengths of the Skyn, six key challenges in the collection and processing of data include (1) identifying consumed alcohol; (2) identifying environmental alcohol; (3) identifying and determining the source of missing or invalid data; (4) achieving high participant adherence; (5) integrating Skyn and self-report data; and (6) implications for statistical inference. In this report we outline these challenges, provide recommendations to address them and identify future needs., Design and Settings: Procedures from several laboratory and field-based pilot studies are presented to demonstrate practical recommendations for Skyn use. Data from a pilot study including a 7-day ecological momentary assessment period are also presented to evaluate effects of environmental alcohol on BACtrack Skyn readings., Conclusions: To address challenges in the collection and processing of data from the BACtrack Skyn alcohol biosensor, researchers should identify goals in advance of data collection to anticipate the processing necessary to interpret Skyn data. The Transdermal Alcohol Sensor Data Macro (TASMAC) version 2.0 software can help to process data rapidly; identify drinking events, missing data and environmental alcohol; and integrate the sensor with self-report data. Thorough participant orientation and regular contact in field studies can reduce missing data and enhance adherence. Many recommended methods for Skyn use are applicable to other alcohol sensors and wearable devices., (© 2023 Society for the Study of Addiction.)

Objective: There is substantial evidence linking anxiety sensitivity and distress intolerance to depressive symptoms, and further evidence linking depressive symptoms to alcohol and cannabis use. However, the prospective indirect associations of anxiety sensitivity and distress intolerance with alcohol and cannabis use through depressive symptoms remain uncertain. Thus, the current study examined whether depressive symptoms mediated the associations between anxiety sensitivity and distress intolerance with alcohol and cannabis use frequency, quantity, and problems in a longitudinal sample of veterans., Method: Participants ( N = 361; 93% male; 80% White) were military veterans with lifetime cannabis use recruited from a Veterans Health Administration in the Northeastern United States. Eligible veterans completed three semi-annual assessments. Prospective mediation models were used to test for the effects of baseline anxiety sensitivity and distress intolerance on alcohol and cannabis use quantity, frequency and problems at 12 months via depressive symptoms at 6 months., Results: Baseline anxiety sensitivity was positively associated with 12-month alcohol problems. Baseline distress intolerance was positively associated with 12-month cannabis use frequency and quantity. Baseline anxiety sensitivity and distress intolerance significantly predicted increased alcohol problems and cannabis use frequency at 12 months through depressive symptoms at 6 months. There were no significant indirect effects of anxiety sensitivity and distress intolerance on alcohol use frequency or quantity, cannabis use quantity, or cannabis problems., Conclusions: Anxiety sensitivity and distress intolerance share a common pathway to alcohol problems and cannabis use frequency through depressive symptoms. Interventions focused on modulating negative affectivity may reduce cannabis use frequency and alcohol problems.

Objective: Co-use of alcohol and cannabis has been associated with more total negative consequences than single-substance use, but results have been mixed depending on whether the single substance was alcohol or cannabis. The present study used within-person analyses to examine whether co-use increased the risk for experiencing specific acute negative consequences., Method: College students who were co-users of alcohol and cannabis ( N = 341; M age = 19.8 years; 51.3% female; 74.8% White) completed 56 days of five daily surveys across two bursts. We used generalized linear mixed effects models to examine the effects of type of substance use day on specific negative consequences, controlling for consumption and covariates., Results: Relative to both alcohol-only and co-use days, cannabis-only days were associated with decreased likelihood of experiencing hangover, blackout, nausea/vomiting, injury, rude/aggressive behavior, and unwanted sex. Relative to alcohol-only days, cannabis-only and co-use days were associated with an increased likelihood of driving high/drunk. Finally, there was an increased likelihood of hangovers on alcohol-only days compared with co-use days., Conclusions: Days with different types of substance use differed in specific consequences. Most of the negative co-use consequences investigated here appear to be driven by alcohol consumption rather than cannabis use. The results also indicated that these young adults were more likely to endorse driving under the influence of cannabis than alcohol. Interventions for co-use should target alcohol consumption to reduce negative consequences such as blackout, injury, rude/aggressive behavior, and unwanted sex and highlight the dangers of driving under the influence of cannabis.

Human-induced environmental changes, such as the introduction of invasive species, are driving declines in the movement of nutrients across ecosystems with negative consequences for ecosystem function. Declines in nutrient inputs could thus have knock-on effects at higher trophic levels and broader ecological scales, yet these interconnections remain relatively unknown. Here we show that a terrestrial invasive species (black rats, Rattus rattus) disrupts a nutrient pathway provided by seabirds, ultimately altering the territorial behaviour of coral reef fish. In a replicated ecosystem-scale natural experiment, we found that reef fish territories were larger and the time invested in aggression lower on reefs adjacent to rat-infested islands compared with rat-free islands. This response reflected changes in the economic defendability of lower-quality resources, with reef fish obtaining less nutritional gain per unit foraging effort adjacent to rat-infested islands with low seabird populations. These results provide a novel insight into how the disruption of nutrient flows by invasive species can affect variation in territorial behaviour. Rat eradication as a conservation strategy therefore has the potential to restore species interactions via territoriality, which can scale up to influence populations and communities at higher ecological levels., (© 2023. The Author(s).)

Background: The impact of alcohol and cannabis co-use on college student drinking and related outcomes is complex. Specific characteristics or patterns of co-use events beyond drinking quantity may be important to the experience of consequences. The present study used repeated daily surveys to examine the association between co-use (versus use of alcohol only) and drinking rate on negative consequences., Methods: The sample included 318 college students (M age  = 19.8, 47% female, 76% non-Hispanic White) who were co-users of alcohol and cannabis, recruited from three U.S. college campuses. Participants completed 56 days of data collection (number of drinking days ranged from 1 to 38). Two measures of drinking rate were examined: (1) daily rate (number of drinks divided by number of hours spent drinking per day); and (2) peak hour rate (maximum number of drinks consumed in a single hour) to account for anomalous drinking days of long duration. Generalized linear mixed models examined: (1) associations of co-use with peak hour rate (model 1a) and daily rate (model 1b); (2) associations of peak hour rate (model 2a) and daily rate (model 2b) with experiencing any negative consequence; and (3) interactions of co-use with peak hour rate (model 3a) and daily rate (model 3b) on experiencing a consequence., Results: Co-use was positively associated with peak hour rate but not daily rate. Both peak hour and daily rate positively predicted likelihood of experiencing a negative consequence. The interaction of both peak hour and daily rate by co-use was significant such that the association of rate with experiencing a consequence was stronger on alcohol-only days compared to co-use days., Conclusions: Daily drinking rate and peak hour drinking rate are unique and should be considered when discussing drinking patterns. Both predict negative consequences and may be important aspects of interventions for negative drinking-related outcomes among college students., (© 2022 Research Society on Alcoholism.)

Objective: Impulsivity is an established etiological risk factor for alcohol- and cannabis-related outcomes. However, limited work has focused on longitudinal associations between multiple trait impulsivity facets and indices of alcohol and cannabis use among military veterans-a contextually distinct population that evidence unique impulsive personality traits and substance use patterns., Method: A structural equation model (SEM) examined longitudinal associations between five UPPS-P impulsivity facets measured at baseline and six indices of alcohol and cannabis use (i.e., frequency, quantity, and problems) measured at 1-year follow-up among 361 returning Operation Enduring Freedom, Operation Iraqi Freedom, and Operation New Dawn (OEF/OIF/OND) veterans., Results: Findings indicated baseline sensation seeking was significantly positively associated with 1-year alcohol use frequency (β = .18); baseline negative urgency was positively associated with alcohol use problems (β = .31); and baseline lack of perseverance (β = .25) and sensation seeking (β = .21) were positively associated with 1-year cannabis use problems. None of the baseline impulsivity facets were associated with 1-year alcohol use quantity, cannabis use frequency, or cannabis use quantity., Conclusions: Results provide preliminary support that impulsivity may play a unique role in understanding alcohol- and cannabis-related problems over time among veterans. Further, results suggest that specific impulsivity facets are prospectively associated with cannabis problems (i.e., lack of perseverance and sensation seeking) and alcohol problems (i.e., negative urgency). Findings reinforce the importance of differentially evaluating impulsivity-substance use associations within contextually distinct populations (e.g., adolescent, veteran), and highlight potentially meaningful intervention targets among veterans. However, replication is needed with stronger temporal controls and more diverse veteran subsamples. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Substance use in young adulthood and polysubstance users (PSU), in particular, pose unique risks for adverse consequences. Prior research on young adult PSU has identified multiple classes of users, but most work has focused on college students. We examined PSU patterns by age and college attendance during young adulthood in two nationally representative samples. Using National Epidemiological Survey on Alcohol and Related Conditions (NESARC) Wave 1 and NESARC-III data sets, multigroup latent class analysis (MG-LCA) was employed to examine PSU patterns based on age (18-24 vs. 25-34) and determine whether solutions were similar (i.e., statistically invariant) by college attendance/graduation. Classes were estimated by binary past-year use of sedatives, tranquilizers, opioids/painkillers, heroin, amphetamines/stimulants, cocaine, hallucinogens, club drugs, and inhalants, and past-year frequency of alcohol, cigarette, and cannabis use. PSU patterns are largely replicated across waves. Model fit supported 3-class solutions in each MG-LCA: Low frequency-limited-range PSU (alcohol, cigarettes, and cannabis only), medium-to-high frequency limited-range PSU (alcohol, cigarettes, and cannabis only), and extended-range PSU (ER PSU; all substances). Apart from one model, MG-LCA solutions were not invariant by college attendance/graduation, suggesting important differences between these groups. Except for alcohol, cannabis, and cigarette use frequency, results showed that probabilities of illicit and prescription drug use declined in the older age group. Findings also supported examining college and noncollege youth separately when studying PSU. ER PSU may be uniquely vulnerable to coingesting substances, particularly for nongraduates, warranting future research to classify patterns of simultaneous PSU and identify predictors and consequences of high-risk combinations (e.g., alcohol and opioids). (PsycInfo Database Record (c) 2022 APA, all rights reserved).

There is considerable debate about whether Working Memory (WM) training specifically results in far-transfer improvements in executive cognitive function (ECF) rather than improvements on tasks similar to the training tasks. There has also been recent interest in whether WM training can improve ECF in clinical populations with clear deficits in ECFs. The current study examined the effects of WM training compared with non-WM adaptive Visual Search (VS) control training (15 sessions over 4 weeks) on various measures of ECF, including delay discounting (DD) rate, inhibition on flanker, color and spatial Stroop tasks, and drinking in a community-recruited sample with Alcohol Use Disorder (AUD, 41 men, 41 women, mean age = 21.7 years), who were not in treatment or seeking treatment, and non-AUD healthy controls (37 men, 52 women, mean age = 22.3 years). Both WM and VS training were associated with improvements on all ECF measures at 4 weeks and 1-month follow-up. WM and VS training were associated with reductions in both DD rates and interference on Stroop and Flanker tasks in all participants, as well as reductions in drinking in AUD participants that remained apparent one month post training. The results suggest that nonspecific effects of demanding cognitive training, as opposed to specific WM training effects, could enhance ECF, and that such enhancements are retained at least one-month post-training., Competing Interests: Conflicts of interest/Competing interests. The authors (Peter Finn, Luca Nemes, Allen Bailey, Rachel Gunn, Elizabeth Wiemers, and Thomas Redick) declare that they have no conflict of interest in any aspect of the data collection, analysis, interpretation, or manuscript preparation.

Objective: Simultaneous alcohol and cannabis use is common among college students and associated with more consumption and consequences compared to single-substance use. This study examined occasions of simultaneous use and compared planned occasions to unplanned occasions with respect to motives, contexts, consumption, and consequences., Method: College student simultaneous users ( N = 341; 53% women; 74% White) completed five daily surveys for 54 days. Mixed-effects models examined motives and contexts of simultaneous use occasions as a function of whether alcohol and cannabis use were (a) both planned versus (b) unplanned, no use planned, or (c) unplanned, single-substance use planned and whether alcohol and cannabis consumption and negative simultaneous use-related consequences varied across planned versus unplanned occasions., Results: Social and enhancement motives were related to planned simultaneous use; offered and coping motives were associated with planned single-substance use that became simultaneous use (vs. planned simultaneous use). Compared to unplanned use, planned simultaneous use was negatively associated with using at home or alone, and positively associated with using with others, more intoxicated people, and more people using cannabis. Planned simultaneous use was associated with more alcohol and cannabis consumption. No significant differences were found for negative consequences., Conclusions: Planned simultaneous use was motivated by social and enhancement reasons, whereas planned single-substance use that became simultaneous use was more likely motivated by offers or for coping. Planned simultaneous use resulted in greater consumption, but not negative consequences. Results provide specific motives and contexts associated with unplanned and planned simultaneous use to be incorporated into real-time interventions. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Purpose: The purpose of this review is to discuss the literature regarding the concurrent use (co-use) of alcohol and cannabis and competing hypotheses as to whether cannabis acts as a substitute for (i.e., replacing the effects of alcohol, resulting in decreased use) or a complement to (i.e., used to enhance the effects of alcohol, resulting in increased use) alcohol. The impact of cannabis use on alcohol-related outcomes has received increased attention in the wake of ongoing legalization of cannabis for both medical and recreational purposes. Evidence for both hypotheses exists in the literature across a broad range of data collection methods and samples and is carefully reviewed here. In addition, various mechanisms by which cannabis may act as an alcohol substitute or complement are explored in depth with the goal of better understanding equivocal findings., Search Methods: This review includes articles that were identified from a search for studies on alcohol and cannabis co-use, with a specific focus on studies exploring complementary versus substitution aspects of co-use. Search terms were included in Google Scholar, PsycINFO, MEDLINE, and Web of Science. Eligible studies were those that measured alcohol and cannabis co-use in human samples in laboratory, survey, or ecological momentary assessment studies, or that directly referenced substitution or complementary patterns of use., Search Results: Search results returned 650 articles, with 95 meeting inclusion criteria., Discussion and Conclusions: Results of this review reveal compelling evidence for both substitution and complementary effects, suggesting nuanced yet significant distinctions across different populations examined in these studies. Several mechanisms for the impact of cannabis use on alcohol-related outcomes are identified, including patterns and context of co-use, timing and order of use, cannabinoid formulation, pharmacokinetic interactions, and user characteristics (including diagnostic status), all of which may influence substitution versus complementary effects. This review will inform future research studies examining this topic in both clinical and community samples and aid in the development of treatment and prevention efforts targeting those populations most vulnerable to negative consequences of co-use. Finally, this review highlights the need for additional research in more diverse samples and the use of mixed-methods designs to examine both pharmacological and contextual influences on co-use.

Cannabis refusal self-efficacy, defined as confidence in the ability to refuse cannabis or to avoid cannabis use, is associated with decreased cannabis use. Juvenile justice-involved youth are at high risk for cannabis use and may have lower refusal self-efficacy. While court-involved, non-incarcerated (CINI) and incarcerated youth are groups that are both at high-risk for cannabis use, the experience of incarceration may impact the measurement of refusal self-efficacy for cannabis. The factor structure, measurement invariance, and concurrent validity of the Brief Situational Confidence Questionnaire for Cannabis (BSCQ-M) was assessed among CINI (n = 148) and incarcerated (n = 199) youth (80.7% male, M age  = 16.3). Confirmatory factor analyses indicated that a correlated 3-factor model including positive/good times, negative internal, and negative external situational factors best fit the data. Multigroup measurement invariance testing revealed that the BSCQ-M demonstrated configural, metric, scalar, and residual invariance across CINI and incarcerated samples, indicating measurement invariance across the two groups. Negative binomial regressions revealed that BSCQ-M scores were significantly negatively associated with concurrent cannabis use. Results suggest that the BSCQ-M is a brief, psychometrically sound measure of refusal self-efficacy for cannabis among juvenile justice-involved youth that can be utilized with both CINI and incarcerated youth., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Posttraumatic stress disorder (PTSD) is the most highly co-occurring psychiatric disorder among veterans with cannabis use disorder (CUD). Despite some evidence that cannabis use prospectively exacerbates the course of PTSD, which in turn increases the risk for CUD, the causal nature of the relationship between cannabis and psychiatric comorbidity is debated. The longitudinal relationship between PTSD diagnosis and traumatic intrusion symptoms with cannabis use and CUD was examined using cross-lagged panel model (CLPM) analysis., Methods: Prospective data from a longitudinal observational study of 361 veterans deployed post-9/11/2001 included PTSD and CUD diagnoses, cannabis use, and PTSD-related traumatic intrusion symptoms from the Inventory of Depression and Anxiety Symptoms., Results: A random intercept CLPM analysis that leveraged three waves (baseline, 6 months and 12 months) of cannabis use and PTSD-related intrusion symptoms to account for between-person differences found that baseline cannabis use was significantly positively associated with 6-month intrusion symptoms; the converse association was significant but reduced in magnitude (baseline use to 6-month intrusions: β = 0.46, 95% CI 0.155-0.765; baseline intrusions to 6-month use: β = 0.22, 95% CI -0.003 to 0.444). Results from the two-wave CLPM reveal a significant effect from baseline PTSD to 12-month CUD (β = 0.15, 95% CI 0.028-0.272) but not from baseline CUD to 12-month PTSD (β = 0.12, 95% CI -0.022 to 0.262)., Conclusions: Strong prospective associations capturing within-person changes suggest that cannabis use is linked with greater severity of trauma-related intrusion symptoms over time. A strong person-level directional association between PTSD and CUD was evident. Findings have significant clinical implications for the long-term effects of cannabis use among individuals with PTSD.

Introduction: Previous research has predominately relied on person-level or single characteristics of drinking episodes to characterise patterns of drinking that may confer risk. This research often relies on self-report measures. Advancements in wearable alcohol biosensors provide a multi-faceted objective measure of drinking. The current study aimed to characterise drinking episodes using data derived from a wearable alcohol biosensor., Methods: Participants (n = 45) were adult heavy drinkers who wore the Secure Continuous Remote Alcohol Monitoring (SCRAM) bracelet and reported on their drinking behaviours. Cluster analysis was used to evaluate unique combinations of alcohol episode characteristics. Associations between clusters and self-reported person and event-level factors were also examined in univariable and multivariable models., Results: Results suggested three unique clusters: Cluster 1 (most common, slowest rate of rise to and decline from peak), Cluster 2 (highest peak transdermal alcohol concentration and area under the curve) and Cluster 3 (fastest rate of decline from peak). Univariable analyses distinguished Cluster 1 as having fewer self-reported drinks and fewer episodes that occurred on weekends relative to Cluster 2. The effect for number of drinks remained in multivariable analyses., Discussion and Conclusions: This is the first study to characterise drinking patterns at the event-level using objective data. Results suggest that it is possible to distinguish drinking episodes based on several characteristics derived from wearable alcohol biosensors. This examination lays the groundwork for future studies to characterise patterns of drinking and their association with consequences of drinking behaviour., (© 2021 Australasian Professional Society on Alcohol and other Drugs.)

Background: The reasons for college students to abstain from alcohol and cannabis use on a given day can inform efforts to prevent or intervene in those behaviors. Research on reasons for alcohol nonuse remains in its nascent stages and no study to date has examined reasons for cannabis nonuse on a given day. Here we examine reasons for nonuse among college students after they planned to use alcohol and/or cannabis., Methods: College students (N = 341; M age  = 19.79; 53% women; 74% White) from 3 universities completed 54 days of data collection across which approximately 50% were nonuse days. Each morning, participants indicated whether they planned to use that day; nonuse reasons were assessed the next morning, if applicable. Generalized linear mixed-effects models were used to disentangle within- and between-person effects., Results: On a given nonuse day (at the within-person level), "work" and "school" were reasons associated with having no plan to use alcohol and "to feel in control" was linked to having no plan to use cannabis. "Did not want to get high" was related to forgoing plans (did not use when originally planned) for alcohol use at the within-person level. At the between-person level, "no desire" was associated with no plans for alcohol or cannabis use and "did not want to get high" was related to no plans for cannabis use. "School" and "could not get" were related to forgoing plans for alcohol and cannabis use, respectively, at the between-person level., Conclusion: An examination of earlier intentions for alcohol and/or cannabis use on nonuse days yielded novel findings on the intention-behavior gap. Reasons for nonuse can inform intervention and prevention strategies (e.g., those involving social norms or just-in-time adaptive efforts) for alcohol and cannabis use on college campuses., (© 2021 by the Research Society on Alcoholism.)

Use of alcohol and cannabis together so their effects overlap (simultaneous use) is common among college students and associated with numerous negative consequences. The aim of this study was to gain insight into college students' recent simultaneous use events in order to inform future studies (i.e., generate hypotheses, inform measures/assessments of simultaneous use, and identify factors influencing simultaneous use). Qualitative interviews of simultaneous use experiences among heavy drinking college students ( n = 38) were conducted to better understand reasons for simultaneous use, evaluations of simultaneous use events, and patterns of substance use during simultaneous use events. Findings indicated that students' reasons for simultaneous use included traditional four-factor motive types (i.e., social, conformity, enhancement, and coping), cross-fading motives, harm reduction motives (e.g., to drink less), and reactive/situational reasons (e.g., because it was offered/available). There was variability in participants' subjective evaluations of how positive versus negative simultaneous use events were and how this compared to single-substance events. Evaluation of simultaneous use events depended on patterns of use, external and internal context, and consequences experienced. Additionally, patterns of simultaneous use including order of substances, timing of using each substance, and quantities of substances used were highly variable across participants. Notably, participants endorsed patterns of use they perceived to reduce negative consequences during simultaneous use events. Further research on reasons for simultaneous use and patterns of use may help identify simultaneous use occasions that result in greater risk; identification of high-risk simultaneous use occasions and evaluation of these occasions can then help inform targeted interventions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Objective: Several studies suggest that alcohol and cannabis co-users are heavier drinkers and experience more alcohol-related consequences. However, day-level associations between co-use and drinking levels are mixed. One reason may be that individual characteristics moderate the daily impact of using alcohol alone or in conjunction with cannabis. The theory would suggest that highly impulsive individuals may drink more on co-use days, yet this assertion remains untested. Therefore, the current study tested whether impulsivity moderated the effect of co-use on same-day drinking quantity within veterans, a high-risk sample for substance use and impulsivity. Method: In a longitudinal observational study, co-using veterans ( N = 139) completed three semi-annual assessments reporting on their daily drinking quantity and cannabis use via Timeline Followback ( Observations = 19,245) and impulsivity via the UPPS-P. Mixed effect modeling was used to test hypotheses that co-use (compared to alcohol-only) days would be associated with heavier drinking for those high (but not low) in positive and negative urgency. Results: Significant interactions were found for positive urgency (PU) and lack of perseverance (LP), such that individuals at mean and low levels of PU and LP drank less on co-use (compared to alcohol-only) days. There were no significant interactions for other UPPS-P impulsivity facets. Conclusion: Findings are consistent with a substitution/compensatory effect for individuals at mean and low levels of both UPPS-P facets, and may be a byproduct of frequent cannabis use in veterans. In contrast, findings suggest that co-use and alcohol-only days may be characterized by similarly high levels of drinking for highly impulsive individuals. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Objective: Simultaneous alcohol and cannabis (i.e., marijuana [SAM]) use is highly prevalent among young adults and college students and associated with a number of negative consequences compared to single substance use. The current study examined socio-contextual factors (e.g., physical, situational, social) associated with SAM use versus cannabis-only versus alcohol-only use. Method: Data were collected from college student SAM users ( N = 313, 53% women, M age = 19.79; 74% White; 10% Hispanic/Latinx) who completed two bursts (28 days) of online repeated daily surveys (RDS). RDS were collected five times per day during both bursts (3 months apart). Results: Results suggested that odds of being at home were greater for cannabis-only use compared to SAM and SAM compared to alcohol-only use. Odds of being at a friend's place were greater for SAM compared to alcohol-only and cannabis-only use. Odds of being at a party were greater for SAM compared to alcohol-only use and odds of being at a bar or restaurant were greater for alcohol-only compared to SAM use. Results also suggested that odds of having more people in a location consistently were greater for SAM compared to cannabis-only use, and alcohol-only compared to cannabis-only use. Conclusion: Physical and social contexts (parties, friend's homes, and being around more people) are significantly associated with SAM use occasions. These findings are well-aligned with a social-ecological framework and suggest intervention and prevention efforts should take a comprehensive approach to reduce harms associated with SAM use. Future work is needed to examine these associations in diverse samples. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Biological invasions pose a threat to nearly every ecosystem worldwide. 1 , 2 Although eradication programs can successfully eliminate invasive species and enhance native biodiversity, especially on islands, 3 the effects of eradication on cross-ecosystem processes are unknown. On islands where rats were never introduced, seabirds transfer nutrients from pelagic to terrestrial and nearshore marine habitats, which in turn enhance the productivity, biomass, and functioning of recipient ecosystems. 4-6 Here, we test whether rat eradication restores seabird populations, their nutrient subsidies, and some of their associated benefits for ecosystem function to tropical islands and adjacent coral reefs. By comparing islands with different rat invasion histories, we found a clear hierarchy whereby seabird biomass, seabird-driven nitrogen inputs, and the incorporation of seabird-derived nutrients into terrestrial and marine food chains were highest on islands where rats were never introduced, intermediate on islands where rats were eradicated 4-16 years earlier, and lowest on islands with invasive rats still present. Seabird-derived nutrients diminished from land to sea and with increasing distance to rat-eradicated islands, but extended at least 300 m from shore. Although rat eradication enhanced seabird-derived nutrients in soil, leaves, marine algae, and herbivorous reef fish, reef fish growth was similar around rat-eradicated and rat-infested islands. Given that the loss of nutrient subsidies is of global concern, 7 that removal of invasive species restores previously lost nutrient pathways over relatively short timescales is promising. However, the full return of cross-ecosystem nutrient subsidies and all of their associated demographic benefits may take multiple decades., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: Attention-deficit/hyperactivity disorder (ADHD) is linked prospectively to cannabis; however, no study has examined mechanisms underlying this comorbidity. We examined 5 cannabis motives (i.e., coping with negative affect, sleep, social anxiety, perceived low risk of cannabis, and altered perception) as mediators of the prospective ADHD-cannabis relation. Method: Veterans reporting lifetime cannabis use ( N = 361; 93% male; 80% White) completed three semiannual assessments. Prospective mediation models using structural equation modeling analyzed the indirect effects of baseline ADHD symptoms on 12-month cannabis use and problems via each motive at 6 months. Zero-inflated negative binomial models were employed for both manifest outcomes and ADHD symptoms and motives were each modeled as 1-factor latent variables. Results: Sleep motives was a robust mediator for cannabis use frequency in single mediator models and was marginally significant when examined simultaneously with other motives after accounting for baseline cannabis use, demographics, other substance use, and other psychopathology. Coping with negative affect was the only significant mediator of ADHD symptoms and subsequent cannabis problem severity. Conclusion: Among veterans with ADHD symptoms, sleep disturbance is a salient motive for cannabis use, whereas coping with negative affect is a proximal predictor of cannabis problems. Findings support addressing sleep disturbance in adults with ADHD symptoms and converge with extant literature demonstrating robust associations between coping motives and substance use problems. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Background: Co-use of alcohol and cannabis is highly prevalent among young adults and college students. Between-person reports suggest that co-use is associated with the experience of more frequent consumption and related consequences, compared to single substance use. However, recent studies have found conflicting evidence regarding the impact of co-use use on consumption and consequences in daily or event-level investigations. Conflicting evidence may be due to understudied factors, such as the order in which alcohol and cannabis are used. The current study aimed to examine the effect of substance use order on a) alcohol consumption; b) cannabis consumption; and c) negative alcohol and cannabis consequences., Methods: Data were collected from U.S. undergraduate college student alcohol and cannabis users (N = 258) who completed two 28-day longitudinal online assessment bursts examining alcohol and cannabis co-use patterns. Data were collected five times per day during both bursts (three months apart)., Results: Controlling for between-person alcohol and cannabis use, within-person mixed-effects models indicated that using cannabis first within a co-use day was associated with lower daily alcohol consumption, but greater daily cannabis consumption. Substance use ordering was not linked to consequences, whereas between-person levels of alcohol consumption and within-person number of drinks in a day were positive predictors of consequences., Conclusions: Overall, results highlighted that order of substance use is a robust predictor of consumption on co-use days. Therefore, future research on co-use use should consider patterns of use in addition to level of use., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Alcohol and marijuana/cannabis are frequently used simultaneously (i.e., SAM use). SAM use is complex, and the ways in which alcohol and cannabis are simultaneously used may reveal differential effects. The purpose of this study was to examine day-level effects of distinct alcohol and cannabis product combinations on simultaneous use and consequences on that day., Methods: College student SAM users (N = 274; 50% women; M age  = 19.82 years) were recruited to complete 54 days of data collection, including 5 repeated daily surveys each day. We identified 12 distinct product combinations reported during SAM-use days. We tested 4 reference groups, with one reflecting the most common use pattern and 3 potentially risky use patterns. We considered 3 outcomes (negative consequences, number of drinks, and number of cannabis uses) and used generalized linear mixed-effects models disentangling within- from between-person effects in all analyses., Results: Using multiple products (≥2) of alcohol was consistently linked to higher odds of experiencing a negative consequence. Combining beer with only one cannabis product (leaf or concentrate) was consistently associated with lower odds of a consequence. Combining cannabis with multiple alcohol products was associated with heavier alcohol consumption. Using dual cannabis products also was associated with heavier cannabis consumption, but this pattern was not significantly different than using concentrate only on a given day., Conclusion: This is the first study to examine day-level influences of distinct alcohol and cannabis product combinations on consumption and consequences among young adult SAM users. Findings suggest that mixing alcohol products confers greater risk for negative consequences and heavier consumption, whereas there is little difference in cannabis consumption when using concentrate only vs. 2 cannabis products on a given day, except for concentrate + beer. Our findings support existing protective strategies of not mixing alcohol products and avoiding use of cannabis concentrate for SAM use as well., (© 2020 by the Research Society on Alcoholism.)

There is a high comorbidity between symptoms of depression and cannabis and alcohol use in civilian and veteran populations. Prospective studies attempting to clarify the directionality of these comorbidities have yielded mixed results. Further, the relations between these constructs and impulsive personality, particularly negative urgency (NU, the tendency to act rashly when experiencing emotional distress) warrants further attention, as NU relates to symptoms of depression and alcohol and cannabis use. Importantly, NU partially accounts for the association between symptoms of depression and cannabis and alcohol problems in cross-sectional studies. This study examined alternative theories of directionality in order to better understand the longitudinal associations between symptoms of depression, NU, and cannabis or alcohol use. Three semiannual waves of data (baseline, 6-month, and 12-month) were collected in parallel assessments from a sample of Operation Enduring Freedom, Operation Iraqi Freedom, and Operation New Dawn veterans ( N = 361). Autoregressive cross-lagged panel models were used to test four alternative theory-driven models about the longitudinal associations between the interaction of symptoms of depression and NU and cannabis or alcohol use. Models revealed unique direction of effects specific to each substance, such that the interaction between symptoms of depression and NU at 6 months postbaseline predicted more alcohol use at 12 months postbaseline, whereas more cannabis use at 6 months postbaseline predicted more severe symptoms of depression at 12 months postbaseline. Results suggests alternate directions of effect for cannabis and alcohol use. Future research should examine these patterns over wider assessment periods in order to see more variability and change over time. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Background: Alcohol and marijuana are frequently co-used with overlapping effects. However, the absence of consistent operational definitions delineating simultaneous alcohol and marijuana use (SAM) from concurrent use (CAM) challenges consistent inferences about these behaviors. This study first examined whether daily alcohol and marijuana co-use predicted substance-use related consequences and subjective intoxication; and then evaluated whether competing operationalizations of SAM and CAM were associated with differences in these outcomes on co-use days., Methods: A sample of 341 young adult college students who reported past-month use of both alcohol and marijuana "at the same time so that their effects overlapped" completed a two-wave survey with paired 28-day daily experience sampling bursts examining alcohol and marijuana co-use. Outcomes were (a) daily substance-use related consequences; and (b) daily subjective intoxication. Focal predictors were daily drinks and marijuana uses; daily co-use versus single-substance use (Aim 1) or CAM versus SAM (Aim 2); and their interaction., Results: Participants reported more negative consequences on co-use days versus marijuana-only days and greater subjective intoxication relative to alcohol or marijuana-only days. Competing operationalizations of SAM, defined as daily co-use occurring within 1-240 min in increments of 1 min, found no difference in consequences or subjective intoxication regardless of operationalization., Conclusion: Co-use days involve greater risk than alcohol-only or marijuana-only days. Although there was no evidence of additional daily risk from simultaneous use regardless of the timeframe used to operationalize it, investigating these effects remains challenging due to the generally small timeframe between substances on co-use days in this sample., Competing Interests: Declaration of Competing Interest There are no conflicts of interest to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Historically, cannabis researchers have assumed a single mode and product of cannabis (e.g., smoking plant). However, patterns of use, products (e.g., concentrates, edibles), and modes (e.g. blunts, vaporizers) are diversifying. This study sought to: 1) classify cannabis users into groups based on their use of the full range of cannabis products, and 2) examine user group differences on demographics, cannabis consequences and cannabis use disorder (CUD) symptomatology., Methods: In a sample of college students (data collected in Fall 2017), who used cannabis in the past year (N = 1390), latent class analysis (LCA) was used to characterize cannabis users. We then added demographic characteristics, cannabis consequences, and CUD symptomatology scores separately to LCA models to examine class differences., Results: Five unique classes emerged: high-frequency all-product users, high-frequency plant/moderate-frequency edible and concentrate users, low-frequency plant users, moderate-frequency plant and edible users, and low-frequency edible users. Demographic characteristics, cannabis consequences, and CUD symptomatology differed across classes characterized by frequency as well as product., Conclusions: Results reflect the increasing variety of cannabis products, modes, and use patterns among college students. In this sample, frequency of use remains a strong predictor of cannabis-related consequences, in addition to type of product. As variation in cannabis use patterns continue to evolve, it is essential for researchers to conduct comprehensive assessments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

College students who use alcohol and marijuana often use them simultaneously, so that their effects overlap. The present study examined whether negative consequences experienced by simultaneous alcohol and marijuana (SAM) users vary from those experienced by individuals who use alcohol and marijuana concurrently but not simultaneously (CAM) or single-substance users. We considered 9 types of consequences: cognitive, blackout, vomiting, academic/occupational, social, self-care, physical dependence, risky behaviors, and driving under the influence (DUI). Further, we examined whether consequences experienced by SAM users are attributed to using alcohol, marijuana, or both simultaneously. The sample included past-year alcohol and marijuana users age 18-24 (N = 1,390; 62% female; 69% White; 12% Hispanic) recruited from 3 U.S. college campuses. SAM users experienced a greater overall number of consequences than CAM or alcohol-only users, even controlling for frequency and intensity of alcohol and marijuana use and potentially confounding psychosocial and sociodemographic factors. Experiencing specific consequences differed between simultaneous and concurrent users, but after adjusting for consumption and other covariates, only blackouts differed. In contrast, SAM users were more likely to experience each consequence than alcohol-only users, with strongest effects for DUI, blackouts, and cognitive consequences. Among SAM users, consequences were most likely to be attributed to alcohol and were rarely attributed to simultaneous use. Being a user of both alcohol and marijuana and using alcohol and marijuana together so that their effects overlap each contribute to risk, suggesting there is value in targeting the mechanisms underlying type of user as well as those underlying type of use. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

College entry is associated with marijuana initiation, and co-use of alcohol and marijuana is associated with problematic outcomes, including alcohol-related consequences. The present study explored if: (a) use of marijuana on a given day would be associated with greater alcohol use within the same day; (b) use of marijuana within a given week would be associated with increased alcohol-related consequences in that same week; and (c) the association between marijuana use and alcohol consumption and consequences varies across time or by precollege level of problematic alcohol use. Participants (N = 488 college student drinkers, 59% female) completed assessments of marijuana use, alcohol use, and alcohol consequences across 2 years. Analyses revealed: (a) daily marijuana use predicted greater number of daily drinks and estimated breath alcohol concentration; (b) weekly marijuana use predicted more weekly positive and negative alcohol consequences; (c) the effect of daily marijuana use on alcohol use strengthened over time, while the effect of weekly marijuana use on positive alcohol consequences reduced over time; and (d) precollege level of problematic alcohol use moderated the association between daily marijuana and alcohol use and weekly marijuana use and negative consequences. This study provides the first longitudinal evidence of the association between marijuana use and greater alcohol use and consequences in college students. Future research examining event-level measurement of alcohol and marijuana co-use is important for the prevention of alcohol-related consequences. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Background: Low working memory (WM) capacity is associated with alcohol use disorders (AUDs). The importance of WM to adaptive functioning has led to a recent influx of studies attempting to improve individual WM capacity using various cognitive training methods. The present study aimed to examine the efficacy of complex WM training for improving WM capacity among individuals with AUD., Methods: Individuals were randomized to complete either adaptive WM training or active control training. We applied a methodologically rigorous and structured approach, including a battery of near and moderate transfer measures in those with AUDs and a control group. Additionally, we examined cognitive factors (at baseline) and other predictors of adherence, training task improvement, and transfer., Results: Results suggest improved WM in individuals with AUDs and controls, as evidenced by improved scores on several transfer measures, after adaptive WM training. However, individuals with AUDs showed poorer adherence and less improvement on the training tasks themselves. Neither IQ, WM, sex, nor condition predicted adherence. Level of training task performance, baseline WM, and IQ predicted transfer task improvement., Conclusions: This is the first study to rigorously examine both the efficacy of WM training in those with AUDs, and predictors of successful training program adherence and transfer in a large sample. Among study completers, results suggest that AUD status does not predict training improvement and transfer. However, AUD status did predict lower program adherence. WM training was more effective in those with higher cognitive ability at baseline. This study provides direct translation to the development of cognitive interventions for treating AUD., (© 2018 by the Research Society on Alcoholism.)

Background: The study aims were to examine daily associations between marijuana and alcohol use and the extent to which the association differs as a function of cannabis use disorder (CUD) and/or alcohol use disorder (AUD) diagnosis., Methods: Timeline Followback interview data was collected in a study of veterans (N = 127) recruited from a Veterans Affairs hospital who reported at least 1 day of co-use of marijuana and alcohol in the past 180 days (22,860 observations). Participants reported 40% marijuana use days, 28% drinking days, with 37% meeting DSM-5 criteria for CUD, 40% for AUD, and 15% for both. Use of marijuana on a given day was used to predict a 3-level gender-adjusted drinking variable (heavy: ≥5 (men)/4 (women) drinks; moderate: 1 to 4/3 drinks; or none: 0 drinks). A categorical 4-level variable (no diagnosis, AUD, CUD, or both) was tested as a moderator of the marijuana-alcohol relationship., Results: Multilevel modeling analyses demonstrated that participants were more likely to drink heavily compared to moderately (OR = 2.34) and moderately compared to not drinking (OR = 1.61) on marijuana use days relative to nonuse days. On marijuana use days, those with AUD and those with AUD + CUD were more likely to drink heavily (OR = 1.91; OR = 2.51, respectively), but those with CUD were less likely to drink heavily (OR = 0.32) compared to moderately, nonsignificant differences between any versus moderate drinking in interaction models., Conclusions: Heavy drinking occurs on days when marijuana is also used. This association is particularly evident in individuals diagnosed with both AUD and CUD and AUDs alone but not in those with only CUDs. Findings suggest that alcohol interventions may need to specifically address marijuana use as a risk factor for heavy drinking and AUD., (Copyright © 2018 by the Research Society on Alcoholism.)

Background: To goal of this study was to better understand mechanisms underlying associations between Major Depressive Disorder (MDD) and marijuana use and problems. Specifically, it was hypothesized that negative urgency (NU), the tendency to act rashly while experiencing negative mood states, would uniquely (compared to other impulsivity traits: positive urgency, sensation seeking, premeditation, and perseverance) account for the relationship between MDD and marijuana use and problems., Methods: Data were collected from a sample ( N  = 357) of veterans ( M age = 33.63) recruited from a Veterans Affairs hospital who used marijuana at least once in their lifetime. Participants completed the SCID-NP to assess MDD, a marijuana problems scale, a Time-Line Follow-back to assess six-month marijuana use, and the UPPS-P Impulsive Behavior Scale for impulsivity., Results: Path analysis was conducted using bootstrapped ( k  = 20,000) and bias-corrected 95% confidence intervals (CIs) to estimate mediation (indirect) effects, controlling for age, sex, and race. Analyses revealed a significant direct effect of MDD on NU and NU on marijuana problems. Regarding mediational analyses, there was a significant indirect effect of MDD on marijuana problems via NU. The direct effect of MDD on marijuana problems was reduced, but remained significant, suggesting partial mediation. No other impulsivity scales accounted for the relationship between MDD and marijuana problems. In predicting marijuana use, there were no significant indirect effects for any impulsivity traits, including NU, despite significant bivariate associations between use and NU and MDD., Conclusions: Results suggest that high levels of NU may partially explain associations between MDD and marijuana problems, but not marijuana use. No other facets of impulsivity accounted for the relationship between MDD and marijuana use or problems, underscoring the specificity of NU as a putative mechanism and the importance of assessing NU in treatment settings., Competing Interests: This research was conducted following the ethical guidelines set forth in accordance with the Declaration of Helsinki and the project has been reviewed and approved by the Institutional Review Boards at the Providence VA Medical Center and at Brown University. All subjects provided informed consent.The authors declare that they have no competing interests.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Executive working memory capacity (eWMC) is central to adaptive decision-making. Research has revealed reduced eWMC and higher rates of impulsive decision making in individuals with alcohol use disorders (AUDs: DSM-IV Alcohol Dependence of Alcohol Abuse) and antisocial psychopathology (AP). Recent work has shown that placing a load on working memory (WM) further increases impulsive decision making on the delay discounting (DD) task in those with AUDs and AP. The current study examined the effects of an attention refocusing manipulation to offset the effects of this WM-load on DD rates in control subjects, those with AUDs without AP, and AUDs with AP (AUD-AP). Results revealed that 1) the AUD-AP group had higher DD rates (i.e., more impulsive decision-making) than the AUD group, followed by controls, and 2) attention refocusing after a load is placed on WM was associated with lower DD rates compared to the load without refocusing in both AUD groups, but not controls. Results suggest that refocusing attention after a cognitive load may be an effective cognitive strategy for reducing the impulsivity-enhancing effects of cognitive load on decision making in individuals with AUDs and AP., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Alcohol use disorders (AUDs) are associated with increased discounting of delayed rewards and reduced executive working memory (eWM) capacity. This association is amplified when comorbid with antisocial psychopathology (AP). Furthermore, recent studies suggest that reduced WM capacity is associated with disinhibited decisions reflected by increased impulsive decision making on the delay discounting of rewards task. While discounting of delayed rewards is well studied, the discounting of delayed losses has received significantly less experimental attention., Methods: The current study investigated (i) the rate of discounting of delayed losses in individuals with AUD only (n = 61), AUD with comorbid AP (n = 79) and healthy controls (n = 64); (ii) the relationship between eWM capacity and discounting of delayed losses; and (iii) the effect of a WM load on discounting of delayed losses. Discounting performance was assessed using a computerized discounting of delayed losses task., Results: Results showed that the AUD-only and AUD-AP groups had higher rates of discounting of delayed losses and lower eWM capacity compared to the control groups. Lower individual eWM capacity was associated with increased discounting of delayed losses. However, WM load did not increase discounting rates overall., Conclusions: These results support the hypothesis that greater discounting of delayed losses is associated with AUD and comorbid AP problems and lower individual eWM capacity., (Copyright © 2017 by the Research Society on Alcoholism.)

Marijuana use has been associated with sexual risk behavior, but the mechanisms that underlie this relationship are not well understood. The present study examined whether marijuana acutely increased sexual risk on a behavioral decision-making task and whether sex-related marijuana outcome expectancies influenced sexual risk decisions after marijuana administration. Participants were heterosexual marijuana users (n = 126) who were randomly assigned to 1 of 4 study conditions using a 2 × 2 factorial design crossing drug administration (received 2.8% delta-9-tetrahydrocannabinol [THC] or 0% THC) with instructional set (told THC or told placebo). Participants completed a self-report measure of sex-related marijuana outcome expectancies at baseline and estimated likelihood of using condoms with a new and a steady partner in an interactive sexual role-play task (SRT) after smoking. In gender-specific analyses, there was a significant interaction of drug administration by sex-related outcome expectancies, such that for men in the received-placebo conditions, more salient sex-related marijuana outcome expectancies were associated with increased likelihood for sex without a condom with a new partner. Among women, there was no interaction or main effect of drug administration but more salient sex-related marijuana outcome expectancies were associated with increased likelihood of sex without a condom with a steady but not new partner. Findings suggest marijuana does not acutely increase risk for engaging in sexual risk behaviors. By contrast, sex-related marijuana outcome expectancies may play a more significant role in sexual decision-making process among marijuana users. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)

Background: Marijuana use has been associated with increased risk-taking and impulsive behavior. While pharmacologic effects of marijuana can lead to inhibitory impairment, expectancy of potential impairment may result in compensatory behavioral response by decreasing impulsive decisions and risky behaviors. With the increases in marijuana use and related problems, a better understanding of the individual characteristics associated with marijuana intoxication and risky behavior is needed. This study examined the role of impairment expectancies in marijuana's acute effects on behavioral measures of impulsivity and risk-taking., Methods: Participants (N=136) were regular marijuana users. A balanced placebo design (BPD) was used crossing marijuana administration (i.e., 0% Tetrahydrocannabinol (THC) vs. 2.8% THC) with stimulus expectancy (i.e., Told Placebo vs. Told THC). Marijuana outcome expectancies were measured by self-report and dependent measures included a number of behavioral impulsivity tasks and the balloon analogue risk task (BART)., Results: Among participants who received THC, higher expectancies for cognitive-behavioral impairment (CBI) were related to lower risk-taking on the BART. Among those who received placebo, there was no association between CBI expectancies and BART performance. CBI expectancies did not moderate the stimulus expectancy effect on the BART nor drug or stimulus expectancy effects on impulsivity measures., Conclusions: Results provide initial evidence that expectancies of greater impairment are associated with compensatory behavior on a risk-taking task under acute marijuana intoxication. Future studies should examine the role of impairment expectancies on risk behaviors of substantial public health concern, such as driving while under the influence of marijuana., (Published by Elsevier B.V.)

Previous studies have demonstrated that working memory capacity plays a central role in delay discounting in people with externalizing psychopathology. These studies used a hyperbolic discounting model, and its single parameter-a measure of delay discounting-was estimated using the standard method of searching for indifference points between intertemporal options. However, there are several problems with this approach. First, the deterministic perspective on delay discounting underlying the indifference point method might be inappropriate. Second, the estimation procedure using the R2 measure often leads to poor model fit. Third, when parameters are estimated using indifference points only, much of the information collected in a delay discounting decision task is wasted. To overcome these problems, this article proposes a random utility model of delay discounting. The proposed model has 2 parameters, 1 for delay discounting and 1 for choice variability. It was fit to choice data obtained from a recently published data set using both maximum-likelihood and Bayesian parameter estimation. As in previous studies, the delay discounting parameter was significantly associated with both externalizing problems and working memory capacity. Furthermore, choice variability was also found to be significantly associated with both variables. This finding suggests that randomness in decisions may be a mechanism by which externalizing problems and low working memory capacity are associated with poor decision making. The random utility model thus has the advantage of disclosing the role of choice variability, which had been masked by the traditional deterministic model. (PsycINFO Database Record, ((c) 2016 APA, all rights reserved).)

This study tested a dual-process model of self-control where the combination of high impulsivity (negative urgency - NU), weak reflective / control processes (low executive working memory capacity - E-WMC), and a cognitive load is associated with increased failures to inhibit pre-potent responses on a cued go/no-go task. Using a within-subjects design, a cognitive load with and without negative emotional load was implemented to consider situational factors. Results suggested that: (1) high NU was associated with low E-WMC; (2) low E-WMC significantly predicted more inhibitory control failures across tasks; and (3) there was a significant interaction of E-WMC and NU, revealing those with low E-WMC and high NU had the highest rates of inhibitory control failures on all conditions of the task. In conclusion, results suggest that while E-WMC is a strong independent predictor of inhibitory control, NU provides additional information for vulnerability to problems associated with self-regulation.

This study investigated the influence of executive working memory (EWM) capacity on impulsive decision-making in a sample of young adults (n=623) that varied in degree of externalizing psychopathology (EXT) by examining: (i) the effects of WM load on delay discounting rates, and, (ii) the association between EWM capacity and delay discounting rates. EXT was measured as a latent variable indicated by lifetime problems with alcohol, marijuana, other drugs, childhood conduct, and adult antisocial behavior. Results showed that (i) the WM load increased discounting rates throughout the spectrum of EXT, (ii) EXT was associated with higher discounting rates and lower EMW capacity, and (iii) WM capacity was significantly associated with higher discounting rates when controlling for IQ, but only after a WM load. The results are discussed in terms of the role of EWM capacity in impulsive decision making in EXT.

Although alcohol use disorders (AUDs) have been associated with different aspects of disinhibited personality and antisociality, less is known about the specific relationships among different domains of disinhibited personality, antisociality, alcohol use, and alcohol problems. The current study was designed to address three goals, (i) to provide evidence of a three-factor model of disinhibited personality (comprised of impulsivity [IMP], risk taking/low harm avoidance [RTHA], excitement seeking [ES]), (ii) to test hypotheses regarding the association between each dimension and alcohol use and problems, and (iii) to test the hypothesis that antisociality (social deviance proneness [SDP]) accounts for the direct association between IMP and alcohol problems, while ES is directly related to alcohol use. Measures of disinhibited personality IMP, RTHA, ES and SDP and alcohol use and problems were assessed in a sample of young adults (N=474), which included a high proportion of individuals with AUDs. Confirmatory factor analyses supported a three-factor model of disinhibited personality reflecting IMP, RTHA, and ES. A structural equation model (SEM) showed that IMP was specifically associated with alcohol problems, while ES was specifically associated with alcohol use. In a second SEM, SDP accounted for the majority of the variance in alcohol problems associated with IMP. The results suggest that aspects of IMP associated with SDP represent a direct vulnerability to alcohol problems. In addition, the results suggest that ES reflects a specific vulnerability to excessive alcohol use, which is then associated with alcohol problems, while RTHA is not specifically associated with alcohol use or problems when controlling for IMP and ES., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Negative urgency, the tendency to act rashly when distressed, is characterized by high Neuroticism, low Conscientiousness, and low Agreeableness. Because of this set of characteristics, the authors hypothesized that (1) negative urgency (NU) is a particularly important predictor of externalizing dysfunction; (2) traits that reflect primarily high Neuroticism predict internalizing dysfunction; and (3) traits that reflect primarily low Conscientiousness predict those types of externalizing dysfunction that include intense affect less strongly than does NU. In three studies, the authors showed that negative urgency concurrently predicted alcohol dependence symptoms in disordered women, drinking problems and smoker status in preadolescents, and aggression, risky sex, illegal drug use, drinking problems, and conduct disordered behavior in college students. High Neuroticism traits predicted internalizing dysfunction but predicted none of these externalizing criteria beyond negative urgency. Low Conscientiousness did not add to prediction from negative urgency, except in a few cases. The tendency toward affect-driven rash action may underlie many externalizing behaviors., (PsycINFO Database Record (c) 2012 APA, all rights reserved.)