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BACKGROUND: Adolescence is marked not only by rapid surges in the prevalence of alcohol use disorders (AUDs) but also by remarkable recovery rates, as most adolescent-onset AUDs naturally resolve over time. Little is known about the differential vulnerability of adolescents and adults. Therefore, this study aimed to unravel the moderating role of age by comparing neural alcohol cue-reactivity, an important AUD biomarker, between low-to-high beer-drinking adolescent (n = 50, 16 to 18 years), and adult (n = 51, 30 to 35 years) males matched on drinking severity.METHODS: Associations between beer odor-induced brain activity and AUD diagnosis, severity of alcohol use-related problems, recent alcohol use, binge-drinking frequency, and task-induced craving were investigated across and between age groups in regions of interest thought to be central in alcohol cue-reactivity: the medial prefrontal cortex, anterior cingulate cortex, and striatal subregions (nucleus accumbens and caudate putamen). These analyses were complemented by exploratory whole-brain analyses.RESULTS: Pre-task beer craving increased pre-to-post task in adolescents only. Individual differences in alcohol use, binge drinking, and craving did not relate to beer odor-induced activity. Although region-of-interest analyses did not reach significance, whole-brain analyses showed that adolescents with AUD, compared with adolescents without AUD and adults with AUD, had higher beer odor-induced activity in a large mesocorticolimbic cluster encompassing the right caudate, nucleus accumbens, orbitofrontal cortex, and the olfactory sulcus. Activity in the right caudate and putamen was positively associated with the severity of alcohol use-related problems in adolescents but negatively associated in adults.CONCLUSION: These findings suggest a differential role of alcohol cue-reactivity in adolescents compared with adults with AUD and highlight the need for further studies investigating the role of age in the fundamental processes underlying the development of and recovery from of AUD.

Aims: Substance use disorders (SUD) are associated with cognitive deficits that are not always addressed in current treatments, and this hampers recovery. Cognitive training and remediation interventions are well suited to fill the gap for managing cognitive deficits in SUD. We aimed to reach consensus on recommendations for developing and applying these interventions. Design, Setting and Participants: We used a Delphi approach with two sequential phases: survey development and iterative surveying of experts. This was an on-line study. During survey development, we engaged a group of 15 experts from a working group of the International Society of Addiction Medicine (Steering Committee). During the surveying process, we engaged a larger pool of experts (n = 54) identified via recommendations from the Steering Committee and a systematic review. Measurements: Survey with 67 items covering four key areas of intervention development: targets, intervention approaches, active ingredients and modes of delivery. Findings: Across two iterative rounds (98% retention rate), the experts reached a consensus on 50 items including: (i) implicit biases, positive affect, arousal, executive functions and social processing as key targets of interventions; (ii) cognitive bias modification, contingency management, emotion regulation training and cognitive remediation as preferred approaches; (iii) practice, feedback, difficulty-titration, bias modification, goal-setting, strategy learning and meta-awareness as active ingredients; and (iv) both addiction treatment work-force and specialized neuropsychologists facilitating delivery, together with novel digital-based delivery modalities. Conclusions: Expert recommendations on cognitive training and remediation for substance use disorders highlight the relevance of targeting implicit biases, reward, emotion regulation and higher-order cognitive skills via well-validated intervention approaches qualified with mechanistic techniques and flexible delivery options., Medical Research Future Fund (MRFF) MRF1141214, National Health and Medical Research Council (NHMRC) of Australia GNT2009464

Background. The global increase in lenient cannabis policy has been paralleled by reduced harm perception, which has been associated with cannabis use initiation and persistent use. However, it is unclear how cultural attitudes towards cannabis use might affect the brain processes underlying cannabis use. Methods. Resting state functional connectivity (RSFC) within and between the executive control network, salience network, and default mode network was assessed in 110 near-daily dependent cannabis users and 79 controls from The Netherlands and Texas, USA. Participants completed a questionnaire assessing the perceived benefits and harms of cannabis use from their personal, friends-family’s and country-state’s perspective and reported on their cannabis use (gram/week), DSM-5 cannabis use disorder (CUD) symptoms, and cannabis related problems. Results. RSFC within the dorsal salience network was lower in cannabis users than controls and was negatively associated with cannabis use in the cannabis group. Cultural attitudes – from personal, friends-family’s and country-state’s perspectives – moderated the associations of cannabis use, CUD symptoms, and cannabis use related problems with RSFC within the salience, executive control, and default mode networks. No group differences in between-network RSFC were observed, but personal perceived benefits and country-state perceived harms moderated the association between CUD symptoms and RSFC between the dorsal and ventral default mode network. Conclusions. This study highlights the importance of considering individual differences in the perceived harms and benefits of cannabis use as a factor in the associations between brain functioning and cannabis use, CUD symptoms, and cannabis use related problems.

Aims. Social alcohol use is highly common and associated with heavier alcohol consumption, but most studies have focused on explicit measures of perceived social drinking norms. This study aimed to 1) develop an implicit social attunement (ISA) task to experimentally assess how willingness to drink alcohol is affected by social alcohol drinking (SAD), social non-alcohol drinking (SNAD), and social non-drinking (SND) settings and peer feedback on willingness to drink in these settings, and 2) assess how ISA is associated with explicit social attunement, age, alcohol use and alcohol use related problems. Design. Cross-sectional. Setting and participants. An online assessment completed by an international sample (N = 506, 60.1% female) of 16–60-year-olds recruited from the Netherlands. Measurements. The ISA task and questionnaires assessing alcohol use and alcohol use related problems, age, and explicit social attunement. Findings. Willingness to drink was highest in the SAD setting (p

Cannabis legislation and attitudes towards use are changing. Given that evidence from cultural neuroscience research suggests that culture influences the neurobiological mechanisms underlying behaviour, it is of great importance to understand how cannabis legislation and attitudes might affect the brain processes underlying cannabis use disorder. Brain activity of 100 dependent cannabis users and 84 controls was recorded during an N-back working memory (WM) task in participants from the Netherlands (NL; users = 60, controls = 52) and Texas, USA (TX; users = 40, controls = 32). Participants completed a cannabis culture questionnaire as a measure of perceived benefits (positive) and perceived harms (negative) of cannabis from their personal, friends-family's and country-state's perspectives. Amount of cannabis use (grams/week), DSM-5 CUD symptoms and cannabis use-related problems were assessed. Cannabis users self-reported more positive and less negative (personal and friends-family) cannabis attitudes than controls, with this effect being significantly larger in the TX cannabis users. No site difference in country-state attitudes was observed. TX cannabis users, compared with NL cannabis users, and those cannabis users perceiving more positive country-state attitudes showed a more positive association between grams/week and WM-related activity in the superior parietal lobe. NL cannabis users, compared with TX cannabis users, and those cannabis users with less positive personal attitudes showed a more positive association between grams/week and WM-load-related activity in the temporal pole. Both site and cultural attitudes moderated the association of quantity of cannabis use with WM- and WM-load-related activity. Importantly, differences in legislation did not align with perceived cannabis attitudes and appear to be differentially associated with cannabis use-related brain activity.

The social plasticity hypothesis proposes that social attunement, that is, the adaptation to and harmonization with one's environment, plays a crucial role in the risk for developing alcohol use disorders (AUDs) during adolescence, whereas in adulthood it paradoxically may make individuals more sensitive to the social pull to reduce drinking. This study aimed to develop a valid measure of social attunement: the social attunement questionnaire (SAQ). A total of 26 items were developed and the questionnaire was completed by 576 Dutch mid to late adolescents and adults over three rounds of online data collection. Using exploratory factor analysis in part of the sample (N = 373), the final questionnaire was reduced to two subscales with a total of 11 items. This structure was confirmed using confirmatory factor analysis in the second part of the sample (N = 203). Results showed that the SAQ has acceptable internal consistency, good measurement invariance to gender, and subscales assessing both cognitive as well as behavioural components of social attunement. In line with expectations on alcohol use settings, SAQ scores were not associated directly with alcohol use, but they were predictive of alcohol use when taking into account the interaction between perceived peer drinking and age. The SAQ appears suitable for the assessment of social attunement in (young) adult men and women, particularly assessing the role of social attunement in alcohol use settings. Further research is needed to confirm the utility of the SAQ in older adults and a broader variety of social settings.

Rationale Compromised cognitive control in cannabis use–tempting situations is thought to play a key role in the development of cannabis use disorders. However, little is known about how exposure to cannabis cues and contexts may influence cognitive control and the underlying neural mechanisms in cannabis users. Objectives Working memory (WM) is an attention reliant executive function central to cognitive control. In this study, we investigated how distracting cannabis words affected WM load–dependent performance and related brain activity in near-daily cannabis users (N = 36) relative to controls (N = 33). Methods Brain activity was recorded during a novel N-back flanker WM task with neutral and cannabis flankers added as task-irrelevant distractors. Results On a behavioural level, WM performance did not differ between groups, and the presence of cannabis flankers did not affect performance. However, in cannabis users compared to controls, the presence of cannabis flankers reduced WM load–related activity in multiple regions, including the insula, thalamus, superior parietal lobe and supramarginal gyrus. Conclusions The group specificity of these effects suggest that cannabis users might differ from controls in the way they process cannabis-related cues and that cannabis cue exposure could interfere with other cognitive processes under cognitively demanding circumstances. Future studies should focus on the role of context in cognitive control–related processes like WM and attention to further elucidate potential cognitive impairments in heavy cannabis users and how these relate to loss of control over drug seeking itself.

Background: Concurrent use (co-use) of cannabis and tobacco is common and associated with worse clinical outcomes compared with cannabis use only. The mechanisms and interactions of cannabis use disorder (CUD) symptoms underlying co-use remain poorly understood. Methods: We examined differences in the symptom presence and symptom network configurations between weekly cannabis users who use tobacco daily (co-users, n=789) or non- or nondaily (nondaily co-users, n=428). Results: First, we identified a range of symptoms ( craving, failed reduce or quit attempts, neglected responsibilities, and negative social effects) that are most central to the highly interconnected CUD symptom network. Risky cannabis use was mostly associated with negative social and health effects, and independent of other CUD symptoms. Craving symptoms act as a bridge between different CUD and withdrawal symptoms. Among co-users, (1) craving is more strongly associated with negative psychosocial effects, (2) feelings of depression and negative health effects are more central to the network, and (3) the negative health effects are more strongly associated with failed attempts to reduce or quit attempts compared with nondaily co-users. Discussion: Our results go beyond existing findings focused on the mere increase in CUD symptom presence, and speak to the potential synergistic effects of co-use on dependence and withdrawal symptoms. We outline clinical implications with respect to targeting specific CUD symptoms in co-users, and point to future research to disentangle tobacco and cannabis craving symptoms.

Aims: This study experimentally tested whether there is a gateway-type effect of cannabis administration on tobacco and cocaine motivation and whether motivational responses predicted use 6 months later.Methods: A 2 (condition: active cannabis vs. placebo joint)x3 (substance stimulus type: tobacco, cannabis, and cocaine) factor within-subjects design for both implicit and explicit motivation. Both experimental sessions were conducted in a cannabis dispensary ("coffeeshop") in Amsterdam and were separated by similar to 1 week, followed by a 6-month online follow-up. Eighty-five participants between 18 and 27 years of age (57% male), who used cannabis, tobacco, and cocaine

Background. Given increases in cannabis potency and cannabis use in newly legalized markets, it remains critical to examine the effects of cannabis on a variety of health outcomes. However, quantification of cannabinoid exposure remains rare in cannabis research. It is unclear whether biospecimen measures of cannabinoid exposure, such as those derived from hair, are associated with common self-report measures of use and cognitive and mental health outcomes. Methods. 74 near-daily cannabis users with cannabis use disorder self-reported their quantity of cannabis use, cannabis use-related problems, estimated cannabis potency, and mental health outcomes, and completed cognitive tests. Hair samples were provided to quantify Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), and cannabinol (CBN) using a liquid chromatography atmospheric pressure chemical ionization-tandem mass spectrometry method. Results. Cannabinoids were detectable in 95.95% of the hair samples from individuals who tested positive on a urine screen for cannabis. Hair-derived Δ9-THC concentrations were positively associated with several measures of self-reported potency (relative potency, potency category, and perceived ‘high’) although Δ9-THC, CBD, or CBN concentrations or THC/CBD ratio were not associated with self-reported quantity of use. Furthermore, self-reported THC percentage (category) and potency (category), but not cannabinoid concentrations, were associated with withdrawal and craving respectively. Self-reported measures of quantity of cannabis use (gram/week), but not cannabinoid concentrations, were associated with cannabis use related problems. Mental health problems were associated with self-reported cannabis use-related problems and withdrawal only. Looking at cognitive outcomes, only a small negative association between a measure of cannabis use related problems and estimated IQ was observed. Conclusions. The use of hair-derived cannabinoid quantification is supported for detecting cannabis use in near-daily users. However, the general lack of associations between hair-derived cannabinoid concentrations and commonly used self-report measures does not support the use of hair analyses for quantifying cumulative cannabinoid exposure at this time. Further research comparing hair-derived cannabinoid concentrations with other biological matrices (e.g. plasma) and self-report is necessary to further evaluate the validity of hair analyses for this purpose. The importance of accurately quantifying cannabinoid exposure in research into the effects of cannabis cannot be overstated given newly permissive legal environments and uptick in use.

AimsCognitive and motivational processes are thought to underlie cannabis use disorder (CUD), but research assessing how cognitive processes [e.g. interference control (IC)] interact with implicit [e.g. attentional bias (AB)] and explicit motivation (i.e. craving) is lacking. We assessed the presence of AB in cannabis users with varying use severity and tested models of moderation, mediation and moderated mediation to assess how AB, craving and IC interact in their association with measures of cannabis use.DesignA cross-sectional study design was used.Setting and participantsEight studies performed by our laboratory in the Netherlands including never-sporadic, occasional (≤ 1/month) and regular cannabis users (≥ 2/week), and individuals in treatment for CUD were combined (n = 560; 71% male).MeasurementsStudies included a classic Stroop task (IC), a cannabis Stroop task (AB) and measures of session-induced and average session craving. Both heaviness of cannabis use (grams/week) and severity of use related problems were included.FindingsOnly those in treatment for CUD showed an AB to cannabis (P = 0.019) and group differences were only observed when comparing CUD with never-sporadic users (P = 0.007). In occasional and regular users, IC was negatively associated with heaviness (β = 0.015, P β = 0.050, P = 0.011) as well as severity of use (β = 0.083, P = 0.009); higher AB was associated with heavier use and more severe problems through increased craving.ConclusionsAttentional bias only appears to be present in cannabis users with the most severe problems and craving appears to mediate the association between attentional bias and both heaviness and severity of use in occasional and regular users. The association of interference control with heaviness but not severity of use may point to subacute intoxication effects of cannabis use on interference control.

Although cannabis use patterns differ between men and women, studies on sex differences on the effects of cannabis on the brain and cognitive control are largely lacking. Working memory (WM) is a component of cognitive control believed to be involved in the development and maintenance of addiction. In this study, we evaluated the association between cannabis use and WM (load) related brain activity in a large sample, enabling us to assess sex effects in this association. The brain activity of 104 frequent cannabis users (63% men) and 85 controls (53% men) was recorded during an N-back WM task. Behavioral results showed a significant interaction between WM load and group for both accuracy and reaction time, with cannabis users showing a relatively larger decrease in performance with increasing WM load. Cannabis users compared to controls showed a relatively smaller reduction in WM (load) related activity in the precuneus and posterior cingulate cortex at higher WM load. This WM (load) related activity was not associated with performance nor cannabis use and related problems. An exploratory analysis showed higher WM-related activity in the superior frontal gyrus in men compared to women. While cannabis users showed higher WM (load) related activity in central nodes of the default mode network, this was not directly attributable to group specific worsening of performance under higher cognitive load. Further research is necessary to assess whether observed group differences increase with higher cognitive load, how group differences relate to measures of cannabis use, and how sex affects these group differences.

Background and aimsGraph theoretic analysis of structural covariance networks (SCN) provides an assessment of brain organization that has not yet been applied to alcohol dependence (AD). We estimated whether SCN differences are present in adults with AD and heavy-drinking adolescents at age 19 and age 14, prior to substantial exposure to alcohol.DesignCross-sectional sample of adults and a cohort of adolescents. Correlation matrices for cortical thicknesses across 68 regions were summarized with graph theoretic metrics.Setting and participantsA total of 745 adults with AD and 979 non-dependent controls from 24 sites curated by the Enhancing NeuroImaging Genetics through Meta Analysis (ENIGMA)–Addiction consortium, and 297 hazardous drinking adolescents and 594 controls at ages 19 and 14 from the IMAGEN study, all from Europe.MeasurementsMetrics of network segregation (modularity, clustering coefficient and local efficiency) and integration (average shortest path length and global efficiency).FindingsThe younger AD adults had lower network segregation and higher integration relative to non-dependent controls. Compared with controls, the hazardous drinkers at age 19 showed lower modularity [area-under-the-curve (AUC) difference = −0.0142, 95% confidence interval (CI) = −0.1333, 0.0092; P-value = 0.017], clustering coefficient (AUC difference = −0.0164, 95% CI = −0.1456, 0.0043; P-value = 0.008) and local efficiency (AUC difference = −0.0141, 95% CI = −0.0097, 0.0034; P-value = 0.010), as well as lower average shortest path length (AUC difference = −0.0405, 95% CI = −0.0392, 0.0096; P-value = 0.021) and higher global efficiency (AUC difference = 0.0044, 95% CI = −0.0011, 0.0043; P-value = 0.023). The same pattern was present at age 14 with lower clustering coefficient (AUC difference = −0.0131, 95% CI = −0.1304, 0.0033; P-value = 0.024), lower average shortest path length (AUC difference = −0.0362, 95% CI = −0.0334, 0.0118; P-value = 0.019) and higher global efficiency (AUC difference = 0.0035, 95% CI = −0.0011, 0.0038; P-value = 0.048).ConclusionsCross-sectional analyses indicate that a specific structural covariance network profile is an early marker of alcohol dependence in adults. Similar effects in a cohort of heavy-drinking adolescents, observed at age 19 and prior to substantial alcohol exposure at age 14, suggest that this pattern may be a pre-existing risk factor for problematic drinking.

To identify neuroimaging biomarkers of alcohol dependence (AD) from structural magnetic resonance imaging, it may be useful to develop classification models that are explicitly generalizable to unseen sites and populations. This problem was explored in a mega‐analysis of previously published datasets from 2,034 AD and comparison participants spanning 27 sites curated by the ENIGMA Addiction Working Group. Data were grouped into a training set used for internal validation including 1,652 participants (692 AD, 24 sites), and a test set used for external validation with 382 participants (146 AD, 3 sites). An exploratory data analysis was first conducted, followed by an evolutionary search based feature selection to site generalizable and high performing subsets of brain measurements. Exploratory data analysis revealed that inclusion of case‐ and control‐only sites led to the inadvertent learning of site‐effects. Cross validation methods that do not properly account for site can drastically overestimate results. Evolutionary‐based feature selection leveraging leave‐one‐site‐out cross‐validation, to combat unintentional learning, identified cortical thickness in the left superior frontal gyrus and right lateral orbitofrontal cortex, cortical surface area in the right transverse temporal gyrus, and left putamen volume as final features. Ridge regression restricted to these features yielded a test‐set area under the receiver operating characteristic curve of 0.768. These findings evaluate strategies for handling multi‐site data with varied underlying class distributions and identify potential biomarkers for individuals with current AD., To identify neuroimaging biomarkers of alcohol dependence (AD) from structural magnetic resonance imaging, we developed classifiers on data collected from multiple sites. Exploratory data analysis revealed that inclusion of case‐ and control‐only sites led to the inadvertent learning of site‐effects. Evolutionary‐based feature selection leveraging leave‐one‐site‐out cross‐validation, to combat unintentional learning, yielded a test‐set area under the receiver operating characteristic curve of 0.768.

Early adolescence is an important transition period during which many mental disorders emerge. The interplay between different internalizing and externalizing mental health problems in adolescence is poorly understood at the within-person level. Executive functioning (EF) in early adolescence has been shown to constitute a transdiagnostic risk factor, but the specificity of the associations between different domains of EF and internalizing/externalizing mental health problems remains unclear. Leveraging data from a large longitudinal panel study of adolescents (TRAILS, n > 1641) assessed at ages 11, 13, and 15, we investigated the network dynamics of different internalizing and externalizing symptoms. We showcase the use of two novel methodological panel network approaches: cross-lagged panel network models (CLPN) and graphical vector autoregressive (GVAR) models. Moreover, we used hierarchical regression models to investigate prospective associations between different measures of EF (working memory, sustained attention, shifting attention) and broadband transdiagnostic dimensions (internalizing/externalizing symptoms). Depressive symptoms emerged as an important bridge connecting clusters of internalizing and externalizing mental health problems in the cross-sectional networks. Importantly, depressive symptoms predicted a range of other internalizing symptoms (i.e., panic, somatic problems, separation anxiety, general anxiety, social phobia) over time, in particular during early adolescence. In contrast, social phobia symptoms were most strongly predicted by other symptoms. Externalizing symptoms, such as oppositional-defiant problems and inattention/hyperactivity predicted depressive and OCD symptoms at the within-person level respectively. We identified important feedback loops with reciprocal associations between different anxiety symptoms (e.g., separation anxiety – general anxiety, and panic symptoms – somatic problems). Different facets of EF assessed at age 11, in particular sustained attention, showed weak but significant prospective associations with internalizing and externalizing symptoms at age 13 and 15. Our findings speak to the importance of attending to depressive symptoms in early adolescence to prevent a spiral of different internalizing symptoms from arising later on.

Background and aims: Lockdown measures aimed at limiting the number of infections and deaths from the coronavirus disease 2019 (COVID-19) have introduced substantial psychosocial stressors in everyday life. We aimed to investigate the influence of the Dutch lockdown on cannabis use and cannabis use disorder (CUD) and investigate relations with change in mental wellbeing and experienced psychosocial stressors during the lockdown.Design: Explorative longitudinal baseline-, pre- and during lockdown survey study.Setting: The Netherlands, online between January 2019 and May 2020.Participants: Community sample of 120 monthly to daily cannabis users and reference group of 63 non-using controls.Measurements: Change in cannabis use and CUD symptom severity from baseline to pre-lockdown to post-lockdown. Change in cannabis use motives, mental health, quality of social relationships and job status from pre-lockdown to post-lockdown.Findings: In cannabis users, lockdown related to increased cannabis use (B = 1.92, 95% CI 0.23-3.61, p = 0.027), but not CUD symptom severity. Cannabis users experienced 30% job loss and increased loneliness (p < 0.001, BF10 > 100), while contact with partners (p = 0.005, BF10 = 8.21) and families improved (p < 0.001, BF10 = 19.73), with no differences between cannabis users and control. Generally, mental health problems (all p s > 0.277, all BF10 < 0.139) did not change but individual differences were significant and severity of cannabis use pre-lockdown, COVID-19 related worries, change in anxiety, expansion motives, social motives and family contact all uniquely related to variance in change in cannabis use or CUD.Conclusions: While cannabis use among daily cannabis users in The Netherlands increased at the group level during the period of COVID-19 lockdown, the effect of the first months of lockdown on cannabis use disorder severity and mental wellbeing varied significantly among individual daily cannabis users.

Background and AimsSubstance use disorders (SUD) are associated with cognitive deficits that are not always addressed in current treatments, and this hampers recovery. Cognitive training and remediation interventions are well suited to fill the gap for managing cognitive deficits in SUD. We aimed to reach consensus on recommendations for developing and applying these interventions.DesignDelphi approach with two sequential phases: survey development and iterative surveying of experts.SettingOnline study.ParticipantsDuring survey development, we engaged a group of 15 experts from a working group of the International Society of Addiction Medicine (Steering Committee). During the surveying process, we engaged a larger pool of experts (n=53) identified via recommendations from the Steering Committee and a systematic review.MeasurementsSurvey with 67 items covering four key areas of intervention development, i.e., targets, intervention approaches, active ingredients, and modes of delivery.FindingsAcross two iterative rounds (98% retention rate), the experts reached a consensus on 50 items including: (i) implicit biases, positive affect, arousal, executive functions, and social processing as key targets of interventions; (ii) cognitive bias modification, contingency management, emotion regulation training, and cognitive remediation as preferred approaches; (iii) practice, feedback, difficulty-titration, bias-modification, goal setting, strategy learning, and meta-awareness as active ingredients; and (iv) both addiction treatment workforce and specialized neuropsychologists facilitating delivery, together with novel digital-based delivery modalities.ConclusionsExpert recommendations on cognitive training and remediation for SUD highlight the relevance of targeting implicit biases, reward, emotion regulation, and higher-order cognitive skills via well-validated intervention approaches qualified with mechanistic techniques and flexible delivery options.

Co-use of cannabis and tobacco is common and associated with worse clinical outcomes compared to cannabis use only. The mechanisms and interactions of cannabis use disorder (CUD) symptoms underlying co-use remain poorly understood. We examined differences in the symptom presence and symptom network configurations between daily tobacco co-users (n = 789) and non-or non-daily tobacco users (n = 428). First, we identified a range of symptoms (craving, failed reduce or quit attempts, neglected responsibilities, and negative social effects) that are most central in the highly interconnected CUD symptom network. Risky cannabis use was mostly associated with negative social and health effects and independent of other CUD symptoms. Craving symptoms act as a bridge between different CUD and withdrawal symptoms. Among co-users, a) craving is more strongly associated with negative psychosocial effects, b) feelings of depression and negative health effects are more central to the network, and c) the negative health effects are more strongly associated with failed attempts to reduce or quit attempts compared to non-co-users. Our results go beyond existing findings focused on the mere increase in CUD symptom presence and speak to the potential synergistic effects of co-use on dependence and withdrawal symptoms. We outline clinical implications with respect to targeting specific CUD symptoms in co-users and point to future research to disentangle tobacco and cannabis craving symptoms.

BACKGROUND: Reinforcement models identify negative affect (NA) and positive affect (PA) to be important momentary determinants and outcomes of cannabis use. Sensitization and allostatic models further suggest that these mood-cannabis associations are stronger among individuals with more cannabis-related problems. Despite this theoretical background and the fact that cannabis is commonly used for its mood-enhancing effects among college students, surprisingly, little is known about the momentary associations between mood and cannabis use in this population.AIMS: To examine the associations between (a) momentary within-person variations in NA (worried, stressed, nervous) and PA (happy, enthusiastic, proud, excited) and intention to use cannabis within the next hour, (b) the within-person variations in time elapsed since last cannabis use, amount used and momentary NA and PA, and (c) to test whether cannabis-related problems moderate the stated associations.METHOD: Eighty, more-than-weekly, cannabis using students at the University of Amsterdam reported on cannabis use, NA and PA three times daily for 14 consecutive days. Mixed-effects models were performed to analyze the dataset.RESULTS: Within-persons, relatively high PA and low NA were associated with a higher likelihood of intending to use cannabis. Within-persons, more recent and greater amounts of cannabis use were associated with relatively high PA. More recent cannabis use was associated with relatively low NA. Cannabis-related problems did not moderate the associations.CONCLUSIONS: While recent cannabis use related to higher PA and lower NA, high PA but low NA preceded use, supporting positive reinforcement rather than negative reinforcement in this college sample of regular cannabis users.

The aim of this review is to discuss the most recent evidence for the short-term and long-term effects of cannabis on cognition. The evidence that cannabis intoxication is associated with short-term impairment across several basal cognitive domains, including learning and (episodic) memory, attentional control, and motor inhibition is increasing. However, evidence regarding the effects of long-term heavy cannabis use on cognition remains equivocal. Cannabis research suffers from difficulties in measuring cannabis exposure history, poor control over potential subacute effects, and heterogeneity in cognitive measures and sample composition. Multidisciplinary collaborations and investment in studies that help overcome these difficulties should be prioritized.

BACKGROUND: While cannabis use in women is increasing worldwide, research into gender differences in cannabis use disorder (CUD) symptomology is lacking. In response to limited effectiveness of addiction treatment, research focus has been shifting from clinical diagnoses towards interactions between symptoms, as patterns of symptoms and their interactions could be crucial in understanding etiological mechanisms in addiction. The aim of this study was to evaluate the CUD symptom network and assess whether there are gender differences therein.METHODS: A total of 1257 Dutch individuals reporting weekly cannabis use, including 745 men and 512 women, completed online questionnaires assessing DSM-5 CUD symptoms and additional items on plans to quit or reduce use, cigarette use, and the presence of psychological diagnoses. Gender differences were assessed for all variables and an Ising model estimation method was used to estimate CUD symptom networks in men and women using network comparison tests to assess differences.RESULTS: There were gender differences in the prevalence of 6 of the 11 symptoms, but symptom networks did not differ between men and women. Cigarette use appeared to only be connected to the network through withdrawal, indicating a potential role of cigarette smoking in enhancing cannabis withdrawal symptoms. Furthermore, there were gender differences in the network associations of mood and anxiety disorders with CUD symptoms.CONCLUSION: The association between smoking and withdrawal as well as gender differences in the role of comorbidities in the CUD network highlight the value of using network models to understand CUD and how symptom interactions might affect treatment.

Contains fulltext : 219494.pdf (Publisher’s version ) (Closed access) While imaging studies have demonstrated volumetric differences in subcortical structures associated with dependence on various abused substances, findings to date have not been wholly consistent. Moreover, most studies have not compared brain morphology across those dependent on different substances of abuse to identify substance-specific and substance-general dependence effects. By pooling large multinational datasets from 33 imaging sites, this study examined subcortical surface morphology in 1628 nondependent controls and 2277 individuals with dependence on alcohol, nicotine, cocaine, methamphetamine, and/or cannabis. Subcortical structures were defined by FreeSurfer segmentation and converted to a mesh surface to extract two vertex-level metrics - the radial distance (RD) of the structure surface from a medial curve and the log of the Jacobian determinant (JD) - that, respectively, describe local thickness and surface area dilation/contraction. Mega-analyses were performed on measures of RD and JD to test for the main effect of substance dependence, controlling for age, sex, intracranial volume, and imaging site. Widespread differences between dependent users and nondependent controls were found across subcortical structures, driven primarily by users dependent on alcohol. Alcohol dependence was associated with localized lower RD and JD across most structures, with the strongest effects in the hippocampus, thalamus, putamen, and amygdala. Meanwhile, nicotine use was associated with greater RD and JD relative to nonsmokers in multiple regions, with the strongest effects in the bilateral hippocampus and right nucleus accumbens. By demonstrating subcortical morphological differences unique to alcohol and nicotine use, rather than dependence across all substances, results suggest substance-specific relationships with subcortical brain structures. 15 p.

Background and Aim. Cognitive and motivational processes are thought to underlie cannabis use disorder (CUD), but research assessing how cognitive processes (e.g. interference control (IC)) interact with implicit motivational processes (e.g. attentional bias (AB)) and explicit motivation (i.e. craving) is lacking. We assessed the presence of AB in cannabis users with varying use severity and tested models of moderation, mediation, and moderated mediation to assess how AB, craving, and IC interact in their association with measures of cannabis use. Design. Cross-sectional. Setting and Participants. Eight studies performed in the Netherlands including never-sporadic, occasional (≤ 1/month), and regular cannabis users (≥ 2/week), and individuals in treatment for CUD were combined (N = 560; 71% male). Measurements. All studies included a Classic Stroop task to assess IC, a Cannabis Stroop task to assess AB, and a pre- and post-session measure of craving. Both heaviness of cannabis use (grams per week) and severity of use related problems (CUDIT-R scores) were included. Findings. Only those in treatment for CUD showed an AB and group differences in AB were only observed when comparing those in treatment with never to sporadic users. Looking at occasional-regular users, IC was negatively associated with heaviness, but not severity of use. There was no direct association between AB and measures of cannabis use. However, average craving during the session, but not session induced craving, mediated this association between AB and heaviness as well as severity of use; higher AB was associated to heavier use and more severe problems through increased craving. Conclusions. AB was only present in cannabis users with the most severe problems and craving mediated the association between AB and both heaviness and severity of use in occasional to regular users. Furthermore, the association of IC with heaviness but not severity of use may point to sub-acute effects.

The social plasticity hypothesis proposes that social attunement, i.e., the adaptation to and harmonization with one’s environment, plays a crucial role in the risk for developing alcohol use disorders (AUDs) during adolescence, while in adulthood, it may paradoxically make individuals more sensitive to the social pull to reduce drinking. This study aimed to develop a valid measure of social attunement: the social attunement questionnaire (SAQ). A total of 26-items were developed and the questionnaire was completed by 576 participants over three rounds of online data collection. Using exploratory factor analysis in part of the sample (N = 373), the final questionnaire was reduced to two subscales with a total of 11 items. This structure was confirmed using confirmatory factor analysis in the second part of the sample (N = 203). Results showed that the SAQ has acceptable internal consistency, good measurement invariance to gender, and subscales assessing both cognitive as well as behavioural components of social attunement. In line with expectations on alcohol use settings, SAQ scores were not directly associated with alcohol use, but they were predictive of alcohol use when taking into account the interaction between perceived peer drinking and age. The SAQ appears suitable for the assessment of social attunement in (young) adult men and women, particularly assessing the role of social attunement in alcohol use settings. Further research is needed to confirm the utility of the SAQ in older adults and a broader variety of social settings.