Reactivity to in vivo marijuana cues among cannabis-dependent adolescents

Using Latent Profile Analysis to Examine Cannabis Use Contexts: Associations with Use, Consequences, and Protective Behaviors

OBJECTIVE

College students represent a large portion of the population, and report high rates of cannabis use and related negative outcomes, including interpersonal problems, risky behaviors, or physical dependency. The contexts in which students use cannabis (e.g., at a party, when feeling down or depressed, after a fight with a loved one) likely affect their risk of experiencing consequences. We aimed to discern profiles of cannabis use contexts and compare profiles on use frequency, consequences, and the use of cannabis protective behavioral strategies (PBS).

METHOD

College students were surveyed regarding their cannabis use contexts, frequency, consequences, and PBS use (n = 265; female = 72.8%). We used Latent Profile Analysis to identify patterns of cannabis use contexts and auxiliary testing to compare profiles on use frequency, consequences, and PBS use.

RESULTS

Our examination revealed three latent profiles of cannabis use. The Social Use Profile was associated with use in predominantly social/uplifting contexts. The Physical & Emotional Pain Profile was also associated with use in these contexts but was defined by additional use in response to pain. The All Contexts Profile was associated with frequent use in all contexts, including those that were least endorsed by the other profiles. Profiles differed in cannabis use frequency, PBS use, and the number of consequences experienced, such that profiles were more likely to be associated with more frequent cannabis use, higher risk of experiencing use-consequences, and using fewer PBS as the number of use contexts increased across the profiles.

CONCLUSIONS

The contexts in which people use cannabis are associated with cannabis risk and protection. Prevention and intervention efforts may benefit from considering contexts of cannabis use.

Cannabis craving in response to alcohol cues in the laboratory and in daily life among adolescents ages 15-17 years

BACKGROUND

Most adolescents who drink alcohol also use cannabis, and adolescents who use both substances experience worse long-term outcomes than adolescents who use only one or the other. Recent clinical trials with adolescents and emerging adults show that alcohol cues are associated with elevated cannabis craving in the natural environment but not in the laboratory, highlighting cross-cue reactivity as a potential intervention target. This study extends this work to a younger sample of adolescents at an earlier stage of substance use to examine the generalizability of prior findings and inform etiological mechanisms.

METHODS

Participants were 81 adolescents aged 15-17 years who endorsed past-month alcohol and lifetime cannabis use. They completed a laboratory cue reactivity protocol where they rated their cannabis craving during alcohol cue and control conditions. They also completed 24 days of ecological momentary assessment where they reported multiple times per day on their cannabis craving and whether alcohol cues were visible.

RESULTS

Mixed models demonstrated lower cannabis craving following alcohol cue presentation in the laboratory compared to control cues, but higher cannabis craving during moments when alcohol was visible in daily life compared to moments when alcohol was not visible. Frequency of cannabis use at baseline was associated with greater cannabis craving in the laboratory and in daily life regardless of cue type or alcohol visibility, and cannabis craving following alcohol cue presentation in the laboratory was positively related to daily life cannabis craving across contexts.

CONCLUSIONS

This study adds to prior work suggesting that daily life cannabis craving is elevated when alcohol cues are visible. This cross-cue reactivity may be one factor that drives and maintains alcohol and cannabis use in adolescence.

Restructuring reward: A pilot study to enhance natural reward response in adults with cannabis use disorder

BACKGROUND

Hedonic dysregulation is a core mechanism of addiction. There is a dearth of research on hedonic dysregulation in cannabis use disorder (CUD). The current study tested whether personalized scripted imagery may be an efficacious approach to remediate reward functioning in adults with CUD.

METHODS

Adults with CUD (n=10) and non-CUD controls (n=12) completed a single session personalized scripted imagery procedure. Non-drug (i.e. natural) reward and neutral scripts were transcribed and participants listened to the scripts in counterbalanced order. Primary outcomes included positive affect (PA), galvanic skin response (GSR), and cortisol and were assessed at four timepoints. Mixed effects models were used to compare between and within subject effects.

RESULTS

Mixed effects models revealed a Condition (reward vs. neutral) X Group (CUD vs. control) interaction (p=0.01) on PA response, indicating blunted PA response to the neutral script relative to the reward script in CUD participants. Likewise, GSR response in CUD participants was decreased in response to the neutral script relative to the reward script (p=0.034; interaction n.s.). An interaction effect of Group X PA on cortisol response was found (p=.036) indicating that cortisol was positively correlated with PA in healthy control participants, but not CUD participants.

CONCLUSIONS

Adults with CUD may demonstrate acute deficits in hedonic tone under neutral conditions relative to healthy controls. Personalized scripted imagery may be an efficacious tool to remediate hedonic dysregulation in CUD. Cortisol may play a role in healthy positive affect regulation warranting further investigation.

Development and validation of a cannabis cue stimulus set

Regular cannabis use and cannabis use disorder (CUD) have become increasingly prevalent in the United States over the past two decades. Theory and empirical data suggest that the incentive salience of cannabis cues is important to the development and chronicity of CUD. Cannabis cue incentive salience is often assessed with a cannabis cue reactivity paradigm wherein cannabis-related and neutral images are presented. However, prior cannabis cue reactivity studies have been limited by the use of heterogeneous stimuli that were not properly characterized across motivational/affective characteristics, physical image attributes, or non-cannabis-related salient image features (e.g., human presence, face visibility). In order to increase standardization and flexibility of future cannabis cue reactivity tasks, the aim of the present study was to develop and validate a cannabis cue and matched neutral image database comprised of motivational/affective ratings as well as physical image attributes. 234 regular cannabis users varying in primary use method (i.e., bowl, blunt/joint, bong, vaporizer) made motivational (i.e., urge to smoke cannabis) and affective (i.e., arousal, valence) ratings of cannabis-related and neutral images matched on salient, non-cannabis-related features. Physical features (hue, saturation, value) of each image were also analyzed. Motivational/affective ratings of cannabis-related and neutral images differed as expected, and cannabis use frequency and cannabis craving correlations with cannabis image ratings generally supported stimulus validity. Motivational/affective ratings did not significantly differ across cannabis use method-specific images. This database may be a useful tool for future behavioral and neuroscience research on cannabis cue reactivity.

The Multifaceted Therapeutic Role of N-Acetylcysteine (NAC) in Disorders Characterized by Oxidative Stress

Oxidative stress, which results in the damage of diverse biological molecules, is a ubiquitous cellular process implicated in the etiology of many illnesses. The sulfhydryl-containing tripeptide glutathione (GSH), which is synthesized and maintained at high concentrations in all cells, is one of the mechanisms by which cells protect themselves from oxidative stress. N-acetylcysteine (NAC), a synthetic derivative of the endogenous amino acid L-cysteine and a precursor of GSH, has been used for several decades as a mucolytic and as an antidote to acetaminophen (paracetamol) poisoning. As a mucolytic, NAC breaks the disulfide bonds of heavily cross-linked mucins, thereby reducing mucus viscosity. In vitro, NAC has antifibrotic effects on lung fibroblasts. As an antidote to acetaminophen poisoning, NAC restores the hepatic GSH pool depleted in the drug detoxification process. More recently, improved knowledge of the mechanisms by which NAC acts has expanded its clinical applications. In particular, the discovery that NAC can modulate the homeostasis of glutamate has prompted studies of NAC in neuropsychiatric diseases characterized by impaired glutamate homeostasis. This narrative review provides an overview of the most relevant and recent evidence on the clinical application of NAC, with a focus on respiratory diseases, acetaminophen poisoning, disorders of the central nervous system (chronic neuropathic pain, depression, schizophrenia, bipolar disorder, and addiction), cardiovascular disease, contrast-induced nephropathy, and ophthalmology (retinitis pigmentosa).

Weaker Memory Performance Exacerbates Stress-Induced Cannabis Craving in Youths' Daily Lives

Theories of addiction posit that stimuli associated with drug use, including both exteroceptive (e.g., paraphernalia) and interoceptive (e.g., feeling tense or "stressed"), evoke craving and contribute to the pathogenesis of substance misuse. Control over drug cue response and stress is essential for moderating use. Building from laboratory data supporting associations between cue exposure, stress, and craving, this study tested whether these associations generalize to real-world settings and examined whether a well-vetted neurocognitive control capacity, i.e., working memory (WM), moderated associations. Youth (N = 85; 15-24 years) completed baseline and ecological momentary assessments. Cue exposure and participants' average stress predicted higher craving. Youth with weaker WM experienced stronger craving at higher-stress moments but not when faced with cues. Interactions were present for both previous-moment and same-moment stress. Craving among adolescents with stronger WM was not swayed by momentary stress. Findings suggest stronger WM protects against craving at more stressful moments.

Contribution of cannabis-related cues to concurrent reinforcer choice in humans

BACKGROUND

Drug-related cues play a critical role in the development and persistence of substance use disorder. Few human laboratory studies have evaluated how these cues contribute to decisions between concurrently presented reinforcers, and none have examined the specific role of cannabis cues. This study evaluated the contribution of cannabis-related cues to concurrent monetary reinforcer choice in humans.

METHODS

Participants with a cannabis use history (i.e., use in the past two weeks and 50 or more lifetime uses; n = 71) and controls without this history (i.e., 5 or less lifetime uses; n = 79) were recruited using Amazon Mechanical Turk. A cued concurrent choice task was used in which cannabis trials presented two cues (one cannabis and one neutral) side-by-side followed by concurrent monetary offers below each image. The primary dependent measure was choice for cannabis-cued monetary reinforcers on equal value trials. Secondary analyses evaluated individual difference variables related to choice bias.

RESULTS

Participants in the cannabis group showed a significant bias for cannabis-cued choices (mean 76.0%) whereas participants in the control group showed a significant bias against cannabis-cued choices (mean 30.3%). Reaction times on cannabis trials were faster than neutral filler trials and did not differ by group. Cannabis-cued choice was significantly associated with more frequent cannabis use (r = .44), higher cannabis demand intensity (r = .28), and lower cannabis elasticity (r = -.30).

CONCLUSIONS

These findings suggest that cannabis-related cues can influence reinforcer choice and potentially promote disadvantageous decision-making related to non-drug reinforcers.

Investigating a novel fMRI cannabis cue reactivity task in youth

OBJECTIVE

Adult and adolescent studies suggest increased motivational responses to cannabis cues among regular cannabis users. However, functional magnetic resonance imaging (fMRI) studies have not explored neural activation in response to visual cannabis cues among adolescents in the United States. Gaining a better understanding of the neural circuits related to cue-elicited craving during adolescence may shed light on the neural basis for the development of problematic cannabis use that could ultimately be targeted for interventions.

METHODS

41 non-treatment-seeking youth (ages 17-21; mean age = 18.83; 46.3% female) who reported regular cannabis use underwent fMRI scanning involving a visual cannabis cue task and completed self-report and biological measures. Whole-brain activation was examined for cannabis cues compared to non-cannabis cues, and for active versus passive cannabis cues. Associations between self-reported substance use and task activation were examined.

RESULTS

Cannabis images were identifiable to adolescents and were rated as more rewarding than matched non-cannabis images (p < .05). Greater activation was found for the cannabis cues compared to non-cannabis cues in bilateral posterior cingulate, cuneus, fusiform, precuneus, inferior temporal and parahippocampal gyri, as well as left thalamus, medial frontal and superior frontal gyri. Cue-elicited activation was not significantly associated with self-reported cannabis use (ps > 0.05). No differences were observed for the active versus passive cue contrast.

CONCLUSIONS

Cannabis-using youth show more activation to cannabis cues than non-cannabis cues in brain regions underlying incentive salience, reward, and visual attention. This task could be useful for future studies examining neural underpinnings of reward processes in adolescent cannabis users.

Effects of exercise on experimentally manipulated craving for cannabis: A preliminary study

Cannabis is the most commonly used illicit drug in the United States, and craving for cannabis is related to cannabis use. Exercise has been demonstrated to reduce craving for substances. To examine the effects of exercise on cannabis craving, we conducted a 3-week within-subject crossover experiment. Young-adult men (n = 35) and women (n = 11), age 18-25 years (M = 20.76, SD = 1.68), who regularly (≥3 times per week) used cannabis participated in a cue exposure paradigm to stimulate craving. After each of three separate craving inductions, they completed a 10-min bout of exercise that varied in intensity (rest, moderate, vigorous). Craving was assessed before and after the induction, immediately following the exercise, and at three 10-min intervals (total of 30 min). Results of condition-specific, repeated measures analyses of variance showed nonsignificant reductions in immediate postexercise craving for the moderate and vigorous conditions. We used latent growth modeling to examine the trajectory of craving rebound during the 30 min following exercise and explored the effect of baseline weekly cannabis use in predicting craving rebound. Within 30 min postexercise, craving rebounded for both the moderate, F(3, 135) = 9.10, p < .01, and vigorous, F(3, 135) = 3.48, p < .05, conditions. We found that among cannabis users reporting larger quantities of typical weekly cannabis use, craving rebounded more quickly following vigorous than moderate exercise, b = 0.02, SE = 0.02, 95% confidence interval [0.00, 0.06]. The findings suggest that moderate exercise may be useful for reducing craving, particularly among those who use larger quantities of cannabis. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Momentary factors during marijuana use as predictors of lapse during attempted abstinence in young adults

INTRODUCTION

Young adults using marijuana heavily often try multiple times to quit on their own. We sought to identify momentary experiences during marijuana use that could aid in predicting lapse when young adults subsequently attempt abstinence.

METHODS

Young adults (N=34) age 18-25 using marijuana ≥5days/week and planning to quit completed a survey of sociodemographic characteristics, substance use, marijuana expectancies, use motives, perceived social support, and confidence to abstain. They completed ecological momentary assessment (EMA) smartphone reports several times/day for two weeks prior to, then during two weeks of attempted abstinence. Use period EMA reports assessed affect, craving, accessibility, situational permissibility, use, and motivation to abstain. Baseline survey and EMA data were examined in relation to subsequent lapse during attempted abstinence.

RESULTS

Nearly 3 in 4 participants (73.5%) reported lapsing during attempted abstinence from marijuana. On bivariate analyses, lower baseline dependence severity score, negative effect expectancies, perceived family support, and confidence to abstain were each associated with lapse. Of the use period EMA variables, greater percent of days with marijuana use, reports of easy accessibility, and reports of situational permissibility were each associated with lapse. Modeled together, negative effect expectancies, perceived family support, confidence to abstain, and situational permissibility during use were highly accurate in predicting lapse during attempted abstinence.

CONCLUSIONS

Momentary factors may add to conventionally-surveyed characteristics to enhance prediction of lapse during attempted abstinence among young adults with heavy marijuana use. Momentary assessment prior to a quit attempt may thus enable more effective personalized approaches to preventing lapse.

Appetitive startle modulation in the human laboratory predicts Cannabis craving in the natural environment

RATIONALE

Drug-related cues evoke craving and stimulate motivational systems in the brain. The acoustic startle reflex captures activation of these motivational processes and affords a unique measure of reactivity to drug cues.

OBJECTIVES

This study examined the effects of cannabis-related cues on subjective and eye blink startle reactivity in the human laboratory and tested whether these effects predicted youth's cue-elicited cannabis craving in the natural environment.

METHODS

Participants were 55 frequent cannabis users, ages 16 to 24 years (M = 19.9, SD = 1.9; 55% male; 56% met criteria for cannabis dependence), who were recruited from a clinical trial to reduce cannabis use. Eye blink electromyographic activity was recorded in response to acoustic probes that elicited startle reactivity while participants viewed pleasant, unpleasant, neutral, and cannabis picture cues. Following the startle assessment, participants completed an ecological momentary assessment protocol that involved repeated assessments of cue-elicited craving in real time in their real-world environments.

RESULTS

Multilevel models included the presence or absence of visible cannabis cues in the natural environment, startle magnitude, and the cross-level interaction of cues by startle to test whether cue-modulated startle reactivity in the laboratory was associated with cue-elicited craving in the natural environment. Analyses showed that cannabis-related stimuli evoked an appetitive startle response pattern in the laboratory, and this effect was associated with increased cue-elicited craving in the natural environment, b = - 0.15, p = .022, 95% CI [- 0.28, - 0.02]. Pleasant stimuli also evoked an appetitive response pattern, but in this case, blunted response was associated with increased cue-elicited craving in the natural environment, b = 0.27, p < .001, 95% CI [0.12, 0.43].

CONCLUSIONS

Our findings support cue-modulated startle reactivity as an index of the phenotypic expression of cue-elicited cannabis craving.

Cognitive and Mental Health Predictors of Withdrawal Severity During an Active Attempt to Cut Down Cannabis Use

A milestone in cannabis research is the establishment of a clinically relevant cannabis withdrawal syndrome, yet little is known about the underlying mechanisms. We investigated the predictive role of mental health and cognitive factors in withdrawal severity during an active attempt to cut down, relative to uninterrupted cannabis use. Ninety heavy cannabis users were randomly assigned to an experimental or control group. The experimental group was asked to cut down substance use for 1 week. Past week substance use, substance use-related problems, depressive symptoms, cravings, and cognitive control were assessed at baseline. Past week substance use and withdrawal severity were assessed at follow-up. The experimental group reduced their cannabis use more and experienced more withdrawal than the control group. Hierarchical regression analysis per predictor indicated that cannabis use-related problems, depressive symptoms, and cannabis craving, but not cognitive control, predicted stronger withdrawal. Craving uniquely predicted withdrawal in the experimental group. A combined hierarchical regression indicated that only depressive symptoms and cannabis use-related problems uniquely predicted withdrawal across groups. These results suggest that depressive symptoms and cannabis use-related problems are generally indicative of cannabis withdrawal severity, whereas craving specifically predicts cannabis withdrawal during an active attempt to cut-down cannabis use.

Prefrontal functional connectivity measured with near-infrared spectroscopy during smoking cue exposure

Cue reactivity (CR) is an important concept for relapse in substance use disorders (SUD). Although cue exposure (CE) therapy is discussed as relapse prevention, current approaches still need improvement considering its efficacy. From a neurobiological perspective, CR is related to an over-activation in sensitized subcortical structures, their projections to motivationally relevant cortical structures (e.g. orbitofrontal cortex, OFC) and deficient prefrontal inhibitory control. Therefore, we analyzed prefrontal cortical activation and its relation to craving during smoking CE. We focused on the OFC-as a projection area of sensitized subcortical structures-due its importance in the processing of reinforcement value and the dorsolateral prefrontal cortex (dlPFC) based on its importance for behavioral inhibition. Functional near-infrared spectroscopy (fNIRS) was used to assess hemodynamics in prefrontal regions during smoking CE in 24 subjects (n = 12 occasional smokers, n = 12 controls). Subjective craving intensity (minimum craving as marker of baseline inhibition, range as marker of inhibition time course) was additionally assessed. Craving ratings indicated that CR was elicited solely in smokers, not controls. Those subjective ratings correlated with hemodynamic activity in OFC (craving range) and dlPFC (minimum craving). OFC activation was found earlier throughout the CE in smokers compared to controls. Connectivity (seed-based correlation) between OFC and dlPFC was increased in smokers. fNIRS can capture prefrontal hemodynamic activity involved in CR elicited during CE and is therefore a promising method to investigate CR and its implications for relapse prevention in SUD.

Craving cannabis: a meta-analysis of self-report and psychophysiological cue-reactivity studies

AIMS

To estimate the magnitude of cannabis cue-reactivity responses in people who regularly use cannabis.

METHODS

EMBASE, PUBMED, PsycINFO, PsycEXTRA and Project CORK were searched for within-subject comparison studies published between January 2000 and December 2014. Eligible studies compared regular cannabis users' subjective craving or psychophysiological responding when exposed to cannabis cues to their responses to neutral cues and/or to their responses during a baseline assessment. Eligible studies presented original data and were written in English. Fourteen studies met inclusion criteria, but data were not available for two. The 12 included studies contained 393 participants (12-97 participants per study; mean age range: 16.4-32.6 years). Standardized effects sizes were computed for heart rate, skin conductance, skin temperature, blood pressure, event-related potentials (Pz P300) and self-reported craving (Visual Analogue Scales and Marijuana Craving Questionnaire) and synthesized using a multivariate meta-regression model.

RESULTS

On average, cannabis users experienced moderate cue-reactivity, as determined by comparisons with baseline conditions [d = 0.59, 95% confidence interval (CI) = 0.43, 0.74, P < 0.001] and with neutral cue comparisons (d = 0.47, 95% CI = 0.32, 0.62, P < 0.001). This model, which excluded studies at a greater than low risk of bias and included PzP300 studies as a moderator (due to having larger effect sizes), had a moderately low level of heterogeneity of effect size (I²  = 45.6%, Q = 56.97, P = 0.003) and showed no evidence of publication bias. Cue-reactivity was most noticeable (large effect size) when assessed by Pz P300 waves (d = 1.71, 95% CI = 0.77, 2.64, P = 0.0003; I²  = 86%, Q = 36.30, P < 0.001) and least noticeable (trivial effect size) when examining heart rate (d = 0.14, 95% CI = -0.34, 0.62, P = 0.58; I²  = 80%, Q = 20.0, P < 0.001). These subgroup models demonstrated high heterogeneity of effect size.

CONCLUSIONS

Regular cannabis users experience moderate to extremely intense cue-reactivity, such that their attentional biases towards cannabis cues are much stronger than their perceptions of craving for the drug.

Cue-elicited increases in incentive salience for marijuana: Craving, demand, and attentional bias

BACKGROUND

Incentive salience is a multidimensional construct that includes craving, drug value relative to other reinforcers, and implicit motivation such as attentional bias to drug cues. Laboratory cue reactivity (CR) paradigms have been used to evaluate marijuana incentive salience with measures of craving, but not with behavioral economic measures of marijuana demand or implicit attentional processing tasks.

METHODS

This within-subjects study used a new CR paradigm to examine multiple dimensions of marijuana's incentive salience and to compare CR-induced increases in craving and demand. Frequent marijuana users (N=93, 34% female) underwent exposure to neutral cues then to lit marijuana cigarettes. Craving, marijuana demand via a marijuana purchase task, and heart rate were assessed after each cue set. A modified Stroop task with cannabis and control words was completed after the marijuana cues as a measure of attentional bias.

RESULTS

Relative to neutral cues, marijuana cues significantly increased subjective craving and demand indices of intensity (i.e., drug consumed at $0) and Omax (i.e., peak drug expenditure). Elasticity significantly decreased following marijuana cues, reflecting sustained purchase despite price increases. Craving was correlated with demand indices (r's: 0.23-0.30). Marijuana users displayed significant attentional bias for cannabis-related words after marijuana cues. Cue-elicited increases in intensity were associated with greater attentional bias for marijuana words.

CONCLUSIONS

Greater incentive salience indexed by subjective, behavioral economic, and implicit measures was observed after marijuana versus neutral cues, supporting multidimensional assessment. The study highlights the utility of a behavioral economic approach in detecting cue-elicited changes in marijuana incentive salience.

Magnitude and duration of cue-induced craving for marijuana in volunteers with cannabis use disorder

AIMS

Evaluate magnitude and duration of subjective and physiologic responses to neutral and marijuana (MJ)-related cues in cannabis dependent volunteers.

METHODS

33 volunteers (17 male) who met DSM-IV criteria for Cannabis Abuse or Dependence were exposed to neutral (first) then MJ-related visual, auditory, olfactory and tactile cues. Mood, drug craving and physiology were assessed at baseline, post-neutral, post-MJ and 15-min post MJ cue exposure to determine magnitude of cue- responses. For a subset of participants (n=15; 9 male), measures of craving and physiology were collected also at 30-, 90-, and 150-min post-MJ cue to examine duration of cue-effects.

RESULTS

In cue-response magnitude analyses, visual analog scale (VAS) items craving for, urge to use, and desire to smoke MJ, Total and Compulsivity subscale scores of the Marijuana Craving Questionnaire, anxiety ratings, and diastolic blood pressure (BP) were significantly elevated following MJ vs. neutral cue exposure. In cue-response duration analyses, desire and urge to use MJ remained significantly elevated at 30-, 90- and 150-min post MJ-cue exposure, relative to baseline and neutral cues.

CONCLUSIONS

Presentation of polysensory MJ cues increased MJ craving, anxiety and diastolic BP relative to baseline and neutral cues. MJ craving remained elevated up to 150-min after MJ cue presentation. This finding confirms that carry-over effects from drug cue presentation must be considered in cue reactivity studies.

Marijuana use, craving, and academic motivation and performance among college students: An in-the-moment study

INTRODUCTION

Marijuana is the most commonly used illicit substance in the U.S., with high rates among young adults in the state of Colorado. Chronic, heavy marijuana use can impact cognitive functioning, which has the potential to influence academic performance of college students. It is possible that craving for marijuana may further contribute to diminished cognitive and affective functioning, thus leading to poor outcomes for students.

METHODS

College student marijuana users (n=57) were recruited based on heavy use and completed ecological momentary assessment (EMA) via text-messaging. The association between marijuana use and craving in a college setting was explored, as well as how these variables might relate to academic motivation, effort and success. The participants were sent text messages for two weeks, three times per day at random times.

RESULTS

A temporal association between craving and marijuana use was found, where momentary craving positively predicted greater marijuana use. Similarly, as craving levels increased, the number of minutes spent studying decreased at the next assessment point. A negative association between momentary craving for marijuana and academic motivation was found in the same moment. Greater academic self-efficacy positively predicted cumulative GPA, while average minutes spent smoking marijuana was negatively related.

CONCLUSIONS

Using EMA, marijuana craving and use were significantly related. These findings provide further evidence that heavy marijuana use is negatively associated with academic outcomes.

Motivational and control mechanisms underlying adolescent cannabis use disorders: A prospective study

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Adolescents with a CUD had an attentional but no approach bias towards cannabis.

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Cannabis craving significantly predicted cannabis use 6 months later.

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These findings identify craving as a predictor of treatment outcome.

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This study is among the first to investigate neuropsychological mechanisms underlying adolescent CUDs.

Cannabis use disorders (CUDs) are the most prevalent substance use disorders among adolescents in treatment. Yet, little is known about the neuropsychological mechanisms underlying adolescent CUDs. Studies in adult cannabis users suggest a significant role for cognitive control and cannabis-oriented motivational processes, such as attentional bias, approach bias, and craving in CUDs. The current 6-month prospective study investigated the relationships between attentional bias, approach bias, craving, cognitive control, and cannabis use in adolescent patients in treatment for a primary or secondary CUD. Moreover, we investigated if these motivational processes and cognitive control could predict treatment progression after 6 months. Adolescents with a CUD had an attentional but no approach bias towards cannabis. In contrast to adult findings on the role of attentional bias, approach bias and cognitive control, only cannabis craving significantly correlated with current cannabis use and predicted cannabis use-related problems and abstinence from cannabis 6 months later. These findings identify craving as a predictor of treatment outcome, thereby supporting an important role for craving in the course of adolescent cannabis use and dependence. This prospective study is among the first to investigate neuropsychological mechanisms underlying adolescent CUDs, warranting future longitudinal studies.

Effect of oral THC pretreatment on marijuana cue-induced responses in cannabis dependent volunteers

BACKGROUND

The current study tested whether oral Δ(9)-tetrahydrocannabinol (THC: 0-, 10-, and 20-mg) pretreatment would attenuate polysensory cue-induced craving for marijuana.

METHODS

Cannabis dependent participants (7 males and 7 females, who smoked on average 5.4 ± 1.1 blunts daily) completed 3 experimental sessions (oral THC pretreatment dose; counterbalanced order) using a placebo-controlled within-subject crossover design. During each session, participants completed a baseline evaluation and were first exposed to neutral cues then marijuana cues while physiological measures and subjective ratings of mood, craving, and drug effect were recorded.

RESULTS

Following placebo oral THC pretreatment, marijuana (vs. neutral) cues significantly increased ratings of marijuana craving (desire and urge to use, Marijuana Craving Questionnaire (MCQ)-Compulsivity scale), anxious mood and feeling hungry. Males also reported feeling more "Down" during marijuana cues relative to females. Pretreatment with oral THC (10-mg and/or 20-mg vs. placebo) significantly attenuated marijuana cue-induced increases in craving and anxiety but not hunger. Oral THC attenuation of the cue-induced increase in MCQ-Compulsivity ratings was observed in females only. Oral THC produced statistically (but not clinically) significant increases in heart rate and decreases in diastolic blood pressure, independent of cues.

CONCLUSIONS

These marijuana-cue findings replicate earlier results and further demonstrate that oral THC can attenuate selected effects during marijuana multi-cue exposure, and that some of these effects may be sex-related. Results of this study suggest oral THC may be effective for reducing marijuana cue-elicited (conditioned) effects. Further study is needed to determine whether females may selectively benefit from oral THC for this purpose.

Olfactory cue reactivity in nicotine-dependent adult smokers

Cue-elicited reactivity is a significant factor in relapse during smoking quit attempts. Previous research has focused primarily on visual smoking cues, with very limited research examining reactivity to olfactory triggers. Twenty-six adult non-treatment-seeking, nicotine-dependent smokers were exposed to 7 odorants during a cue-reactivity session measuring heart rate, skin conductance, and subjective craving. Cues included 2 cigarette odors (fresh tobacco and cigarette smoke), 2 odors previously identified as smoking-related (freshly mowed grass and coffee), 2 odors previously identified as unrelated to smoking (lavender and burned rubber), and 1 odorless control (propylene glycol). Pairwise comparisons demonstrated that subjective intensity of craving was significantly higher following exposure to the fresh tobacco odor compared with the odorless control (p < .01). A significant main effect for cue type on a physiological measure of arousal was also revealed, with a fresh tobacco odor-elicited significant increase in skin conductance level compared with the odorless control. However, no main effect of cue type on heart rate was found (p = .25). The results of the present study indicate that cigarette odor is an effective olfactory cue that heightens both subjective craving and increases skin conductance in smokers. Future research is needed to evaluate whether avoidance of these odors, or extinction of responses to them, can reduce relapse risk during smoking quit attempts.

Reward-related brain response and craving correlates of marijuana cue exposure: a preliminary study in treatment-seeking marijuana-dependent subjects

OBJECTIVE

: Determining the brain substrates underlying the motivation to abuse addictive drugs is critical for understanding and treating addictive disorders. Laboratory neuroimaging studies have demonstrated differential activation of limbic and motivational circuitry (eg, amygdala, hippocampus, ventral striatum, insula, and orbitofrontal cortex) triggered by cocaine, heroin, nicotine, and alcohol cues. The literature on neural responses to marijuana cues is sparse. Thus, the goals of this study were to characterize the brain's response to marijuana cues, a major motivator underlying drug use and relapse, and determine whether these responses are linked to self-reported craving in a clinically relevant population of treatment-seeking marijuana-dependent subjects.

METHODS

: Marijuana craving was assessed in 12 marijuana-dependent subjects using the Marijuana Craving Questionnaire-Short Form. Subsequently, blood oxygen level dependent functional magnetic resonance imaging data were acquired during exposure to alternating 20-second blocks of marijuana-related versus matched nondrug visual cues.

RESULTS

: Brain activation during marijuana cue exposure was significantly greater in the bilateral amygdala and the hippocampus. Significant positive correlations between craving scores and brain activation were found in the ventral striatum and the medial and lateral orbitofrontal cortex (P < 0.0001).

CONCLUSIONS

: This study presents direct evidence for a link between reward-relevant brain responses to marijuana cues and craving and extends the current literature on marijuana cue reactivity. Furthermore, the correlative relationship between craving and brain activity in reward-related regions was observed in a clinically relevant sample (treatment-seeking marijuana-dependent subjects). Results are consistent with prior findings in cocaine, heroin, nicotine, and alcohol cue studies, indicating that the brain substrates of cue-triggered drug motivation are shared across abused substances.

Integrating brain and behavior: evaluating adolescents' response to a cannabis intervention

Client language (change talk [CT] and counterchange talk [CCT]) is gaining increasing support as an active ingredient of psychosocial interventions. Preliminary work with adults suggests that there may be a neural basis for this. With a diverse sample of adolescent cannabis users, we evaluated the influence of CT and CCT on blood oxygen level dependent (BOLD) response during an fMRI cannabis cue-exposure paradigm. We also investigated how BOLD activation related to treatment outcomes. Adolescent cannabis users (N = 43; 83.7% male; 53.5% Hispanic; M age = 16 years) were presented with CT and CCT derived from their prescan intervention session during the fMRI paradigm. Additionally, BOLD activation during CT (vs. CCT) was tested as a predictor of 1-month follow-up cannabis use behavior (frequency of cannabis use, cannabis problems, cannabis dependence). We observed a significant interaction, with greater activation during CT (vs. CCT) during the cannabis (but not control) cues in several areas key to self-referential processes (uncorrected p < 0.001; medial frontal gyrus, insula). Furthermore, BOLD activation during CT (vs. CCT) during cannabis (but not control) cues in areas that underlie introspection (posterior cingulate, precuneus) was significantly related to youths' 1-month follow-up cannabis use behavior (frequency of cannabis use, cannabis problems, cannabis dependence; uncorrected p < 0.001). These data indicate a unique interaction pattern, whereby CT (vs. CCT) during the cannabis (but not control) cues was associated with significantly greater activation in brain areas involved in introspection. Further, this activation was related to significantly better treatment outcomes for youth.