Modeling stress and drug craving in the laboratory: implications for addiction treatment development

The importance of community engagement in experimental stress and substance use research with marginalized groups: Lessons from research with sexual and gender minority populations

There is a growing need for experimental stress paradigms tailored for use with marginalized groups to better understand the impact of experiencing minoritized stress on substance use outcome. Experimental stress research that examines the role of minority stress in substance use is not only innovative, but also has the potential to improve health equity. However, this research also has anticipated risks. As a result, community-engaged research (CEnR) is critical. CEnR can improve experimental stress and substance use research by engaging applicable communities in research design, recruitment, data interpretation, and dissemination. When conducting CEnR, there are also unique challenges and considerations that need to be taken into account. Recommendations are provided based on prior experiences in experimental stress induction and alcohol research with SGM (sexual and gender minority) groups.

The role of interoceptive awareness in shaping the relationship between desire thinking and cigarette consumption

Interoception, the ability to sense and interpret bodily sensations, has recently emerged as a crucial factor in substance use disorders, including smoking. However, the role of interoceptive awareness in tobacco use remains poorly understood. The relationship between interoceptive ability and addictive behavior is complex, and attempting to conceptualize it as a linear association is unlikely to fully capture the complexity of the mechanisms underlying cravings and urges. We hypothesized that the role played by interoceptive awareness in tobacco use is deeply linked to desire thinking, that is, the conscious and voluntary cognitive process orienting to prefigure images, information, and memories about positive target-related experiences. Desire thinking is typically observed in addiction, where it may contribute to interpreting specific bodily sensations, such as the perceived need for a cigarette. From this perspective, the physiological impact and inclination toward desire thinking contribute to a higher daily cigarette consumption, particularly in situations of low interoceptive awareness. To test this hypothesis, we assessed the physiological activation, the tendency toward desire thinking about smoking, cigarette consumption, and the interoceptive abilities of smoking volunteers. Through a moderation analysis, we showed that desire thinking about smoking predicts a higher number of cigarettes per day in individuals with lower interoceptive awareness (p < .05). These findings suggest that the relationship between desire thinking and interoceptive awareness is a fundamental component of tobacco use, highlighting the importance of taking into account the bodily feedback deriving from the cognitive representation of smoking in addiction research and therapy.

Effects of social housing conditions on ethanol-induced behavioral sensitization in Swiss mice

RATIONALE

In previous animal model studies, it was shown that drug sensitization is dependent upon physical environmental conditions. However, the effects of social housing conditions on drug sensitization is much less known.

OBJECTIVE

The aim of the present study was to investigate the effects of social conditions, through the size of housing groups, on ethanol stimulant effects and ethanol-induced behavioral sensitization in mice.

MATERIALS AND METHODS

Male and female Swiss mice were housed in groups of different sizes (isolated mice, two mice per cage, four mice per cage and eight mice per cage) during a six-week period. A standard paradigm of ethanol-induced locomotor sensitization was then started with one daily injection of 2.5 g/kg ethanol for 8 consecutive days.

RESULTS

The results show that social housing conditions affect the acute stimulant effects of ethanol. The highest stimulant effects were observed in socially isolated mice and then gradually decreased as the size of the group increased. Although the rate of ethanol sensitization did not differ between groups, the ultimate sensitized levels of ethanol-induced stimulant effects were significantly reduced in mice housed in groups of eight.

CONCLUSIONS

These results are consistent with the idea that higher levels of acute and sensitized ethanol stimulant effects are observed in mice housed in stressful housing conditions, such as social isolation.

Sex differences in neural response to an acute stressor in individuals with an alcohol use disorder

BACKGROUND

Alcohol use disorder (AUD) and stress influence overlapping neural circuits in the brain. The literature is mixed regarding the presence of sex differences in the neural response to acute stressors, and this issue has not been examined in individuals with AUD. We validated a stress functional magnetic resonance imaging (fMRI) paradigm in individuals with AUD and tested for sex differences.

METHODS

Twenty-five treatment-seeking individuals with AUD (15M/10F) were recruited to participate in the neuroimaging study linked to a clinical trial of ibudilast (NCT03594435). To assess social-evaluative stress, participants completed the Montreal Imaging Stress Task (MIST). Whole brain and amygdala region-of-interest analyses were conducted. Subjective ratings of anxiety and distress were collected. Repeated measures ANCOVAs were performed to evaluate the effect of stress on anxiety and distress and to evaluate sex differences.

RESULTS

There were trend-level effects of stress on anxiety ratings and amygdala activation (p's = 0.06). There was a significant effect of stress in the bilateral thalamus, ventral tegmental area, and paracingulate (Z's > 4.09, p's < 0.03). There was a trend-level effect of sex on subjective ratings of stress (p's = 0.07). Females had higher amygdala activation in response to stress (p = 0.02). Females also had greater activation than males in the precuneus, posterior cingulate cortex, and right inferior frontal gyrus during acute stress (Z's > 3.56, p's < 0.03).

CONCLUSIONS

This study provides an initial validation of the MIST in a sample of individuals with AUD. It also provides preliminary evidence of sex differences in the response to social-evaluative stress, which is important, given the relevance of stress and negative emotionality as motivators for alcohol use in females.

Cognitive predictors of stress-induced mood malleability in depression

BACKGROUND & OBJECTIVES

Basic attentional control, negative biases in attention and interpretation, and rumination are all cognitive processes associated with depression; however, less is known about their predictive role in depressive mood reactivity and -recovery in response to stress, and their relation to severity of depression.

DESIGN & METHODS

We experimentally induced stress based on an autobiographical imagery script in a sample of 92 participants with Major Depressive Disorder with or without comorbid anxiety disorders. We used simple regression analysis for investigating the roles of state- and trait rumination, attentional networks, and attentional and interpretation biases for predicting stress-induced depressive mood reactivity and -recovery, respectively, and whether they in parallel mediated the association between cognitive processes and depression severity.

RESULTS

Stress-induced depressive mood reactivity was predicted by better orienting ability and more state rumination. Better recovery was predicted by better orienting efficiency and lower negative interpretation bias. Furthermore, the relation between state rumination and depression severity was partially mediated by depressive mood reactivity, however limited by the lack of temporal precedence in the analysis.

CONCLUSIONS

We characterized the relation between cognitive processes and mood malleability in response to stress. Findings could refine theoretical models of depression if causality is established.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04137367.

Stress-Induced Sensitization of Insula Activation Predicts Alcohol Craving and Alcohol Use in Alcohol Use Disorder

BACKGROUND

Stress and alcohol cues trigger alcohol consumption and relapse in alcohol use disorder. However, the neurobiological processes underlying their interaction are not well understood. Thus, we conducted a randomized, controlled neuroimaging study to investigate the effects of psychosocial stress on neural cue reactivity and addictive behaviors.

METHODS

Neural alcohol cue reactivity was assessed in 91 individuals with alcohol use disorder using a validated functional magnetic resonance imaging (fMRI) task. Activation patterns were measured twice, at baseline and during a second fMRI session, prior to which participants were assigned to psychosocial stress (experimental condition) or a matched control condition or physical exercise (control conditions). Together with fMRI data, alcohol craving and cortisol levels were assessed, and alcohol use data were collected during a 12-month follow-up. Analyses tested the effects of psychosocial stress on neural cue reactivity and associations with cortisol levels, craving, and alcohol use.

RESULTS

Compared with both control conditions, psychosocial stress elicited higher alcohol cue-induced activation in the left anterior insula (familywise error-corrected p < .05) and a stress- and cue-specific dynamic increase in insula activation over time (F22,968 = 2.143, p = .007), which was predicted by higher cortisol levels during the experimental intervention (r = 0.310, false discovery rate-corrected p = .016). Cue-induced insula activation was positively correlated with alcohol craving during fMRI (r = 0.262, false discovery rate-corrected p = .032) and alcohol use during follow-up (r = 0.218, false discovery rate-corrected p = .046).

CONCLUSIONS

Results indicate a stress-induced sensitization of cue-induced activation in the left insula as a neurobiological correlate of the effects of psychosocial stress on alcohol craving and alcohol use in alcohol use disorder, which likely reflects changes in salience attribution and goal-directed behavior.

Physical Exercise to Redynamize Interoception in Substance use Disorders

Physical exercise is considered a promising medication-free and cost-effective adjunct treatment for substance use disorders (SUD). Nevertheless, evidence regarding the effectiveness of these interventions is currently limited, thereby signaling the need to better understand the mechanisms underlying their impact on SUD, in order to reframe and optimize them. Here we advance that physical exercise could be re-conceptualized as an "interoception booster", namely as a way to help people with SUD to better decode and interpret bodily-related signals associated with transient states of homeostatic imbalances that usually trigger consumption. We first discuss how mismatches between current and desired bodily states influence the formation of reward-seeking states in SUD, in light of the insular cortex brain networks. Next, we detail effort perception during physical exercise and discuss how it can be used as a relevant framework for re-dynamizing interoception in SUD. We conclude by providing perspectives and methodological considerations for applying the proposed approach to mixed-design neurocognitive research on SUD.

Gestational environmental enrichment prevents chronic social stress induced anxiety- and ethanol-related behaviors in offspring

Epidemiological surveys have shown a strong relationship between maternal stress and offspring's mood disorders. Growing evidence suggested that environmental enrichment (EE) improves cognitive function in models of psychiatric and neurological disorders. However, the potential protective effects of gestational EE on social stress-elicited mood disorders in offspring have not been studied. Knowing that the undeveloped brain is more sensitive to gestational environmental stimuli, we hypothesized that initiating cognitive stimulation, during gestation, would protect against social stress-induced behavioral alterations in adulthood. Therefore, the present study aimed to investigate the effects of gestational EE on social stress-elicited anxiety- and ethanol-related behaviors in adult offspring. EE consisted of free access, of dams, to tubular devices of different shapes, colors, and sizes that were changed regularly. After birth and weaning, young adult offspring were exposed to 19 days of social stress and anxiety-like behavior was evaluated by elevated plus maze, open field, and marbles burying tests. The two-bottle choice (TBC) drinking paradigm was used to assess stress-induced ethanol intake. Results showed that gestational EE prevented social stress-elicited anxiogenic-like effects with no differences in spontaneous locomotor activity. Moreover, in the TBC paradigm, mice pre-exposed to EE consistently showed a significantly decreased consumption and preference for ethanol with no effects on tastants' intakes. Interestingly, gestational EE increased serum BDNF levels, which showed a correlation with measures of anxiety- and ethanol-related behaviors. These findings indicate that some neurodevelopmental changes associated with prenatal EE may counteract adult social stress-induced behavioral alterations through a BDNF mechanism. Therefore, we propose that gestational EE has significant protective and beneficial effects on social stress-induced cognitive impairment. It can also alleviate anxiety-like behavior and subsequent excessive alcohol consumption.

Progesterone Attenuates the Stress Response in Individuals with Alcohol Dependence and Post-Traumatic Stress Disorder - A Pilot Study

OBJECTIVE

Evidence from laboratory studies suggests that progesterone may be effective in reducing stress and craving, and may improve cognitive performance in smokers and individuals with cocaine dependence. The objective of this study was to examine if progesterone would attenuate stress-induced craving, anxiety, affect and physiological measures, as well as improve stress-induced cognitive performance (processing speed and selective attention) in individuals diagnosed with alcohol use disorder (AUD) and post traumatic stress disorder (PTSD).

METHODS

This laboratory study included (n = 13) participants who were diagnosed with current AUD and PTSD who were randomly assigned to recive either progesterone (200mg bid) or placebo in identical looking capsules for 3 days. On the fourth day they completed a laboratory session. In the morning of the test session, they received the last dose of medication and completed the rest of the laboratory procedures. The procedures included presentation in random order of personalized trauma and neutral scripts with relaxation in between. Main outcomes included measure of craving, anxiety, affect and cognitive performance.

RESULTS

Consistent with other research, trauma scripts produced significantly greater increases in craving, anxiety and negative affect when compared with neutral scripts. Progesterone significantly reduced stress-induced symptoms of craving, anxiety, fear, anger and sadness but had no effect on positive emotions (joy, relaxation). Progesterone was effective in ameliorating stress-induced decreases in cognitive performance.

CONCLUSIONS

The findings from this study demonstrate that progesterone can be effective in reducing stress-induced craving, anxiety and negative affect in a laboratory setting in individuals with comorbid AUD and PTSD. Interestingly, progesterone also improved cognitive performance. These findings require replication in a larger clinical trial and may have implications for treatment among individuals with AUD and PTSD.This study was registered as NCT02187224, at www.clinicaltrials.gov.

Laboratory and Real-World Experimental Approaches to Understanding Alcohol Relapse

Alcohol use disorder is highly prevalent and high risk of relapse remains a significant treatment challenge. Therefore, the utility of human laboratory models of relapse to further the understanding of psychobiological mechanisms that precipitate relapse risk and allow testing of novel interventions could be of benefit in expediting the development of effective treatments to target high relapse risk. Stress is a risk factor for the development of AUD and for relapse, and furthermore, chronic alcohol use leads to adaptations in central and peripheral stress biology. Here, we review our efforts to assess the integrity of these stress pathways in individuals with alcohol use disorder and whether adaptations in these systems play a role in relapse risk. Using validated human laboratory procedures to model two of the most common situations that contribute to relapse risk, namely stress and alcohol cues, we review how such models in the laboratory can predict subsequent relapse, and how we can measure specific identified biobehavioral markers of relapse effectively and ecologically in the real world. Finally, we discuss the significant implications of these findings for the development of novel and effective interventions that target stress dysregulation and craving as risk factors to treatment.

Testing pharmacotherapies for alcohol use disorder with cue exposure paradigms: A systematic review and quantitative synthesis of human laboratory trial methodology

Alcohol cue exposure is a widely used experimental paradigm for screening pharmacotherapies for alcohol use disorder (AUD). Medication-related reductions in cue-reactivity signal early efficacy and inform medications development. Yet, across trials, the design of cue exposure, parameter testing, and outcome reporting is heterogeneous. This systematic review is a quantitative synthesis of trial methodologies and effect size estimation for AUD medication-related craving and psychophysiological outcomes under the cue exposure paradigm. A PubMed search was conducted on January 3, 2022 based on identified pharmacotherapies for peer-reviewed articles reported in English. Study-level characteristics, including sample descriptors, paradigm design, analytic approach, and Cochrane Risk of Bias, along with descriptive statistics for cue-exposure outcomes, were coded by two independent raters. Study-level effect sizes were estimated for craving and psychophysiological outcomes separately and sample-level effect sizes were calculated for each medication. Thirty-six trials, comprising 1640 participants and testing 19 different medications satisfied eligibility criteria. All studies reported on biological sex (71% male participants on average). The exposure paradigms implemented used in vivo (n = 26), visual (n = 8), and audio script (n = 2) cues. Some trials included means for craving by medication condition in text (k = 7) or figures (k = 18). The quantitative synthesis included 63 effect sizes (craving kes  = 47; psychophysiological kes  = 16) from 28 unique randomized trials testing 15 medications for effects on cue reactivity. For cue-induced craving, eight medications (kes range: 1-12) demonstrated small-to-medium effects (Cohen's d range: |0.24-0.64|) compared to placebo, with individuals randomized to receive medication reporting lower craving following cue exposure. Recommendations are provided to promote further consilience, so that the utility of cue exposure paradigms can be maximized in the development of effective AUD pharmacotherapies. Future work should explore the predictive utility of medication-related reductions in cue-reactivity on clinical outcomes.

Using lickometry to infer differential contributions of salience network regions during compulsion-like alcohol drinking

Alcohol use disorder extracts substantial personal, social and clinical costs, and continued intake despite negative consequences (compulsion-like consumption) can contribute strongly. Here we discuss lickometry, a simple method where lick times are determined across a session, while analysis across many aspects of licking can offer important insights into underlying psychological and action strategies, including their brain mechanisms. We first describe studies implicating anterior insula (AIC) and dorsal medial prefrontal cortex (dMPF) in compulsion-like responding for alcohol, then review work suggesting that AIC/ventral frontal cortex versus dMPF regulate different aspects of behavior (oral control and overall response strategy, versus moment-to-moment action organization). We then detail our lickometer work comparing alcohol-only drinking (AOD) and compulsion-like drinking under moderate- or higher-challenge (ModChD or HiChD, using quinine-alcohol). Many studies have suggested utilization of one of two main strategies, with higher motivation indicated by more bouts, and greater palatability suggested by longer, faster bouts. Instead, ModChD shows decreased variability in many lick measures, which is unexpected but consistent with the suggested importance of automaticity for addiction. Also surprising is that HiChD retains several behavior changes seen with ModChD, reduced tongue variability and earlier bout start, even though intake is otherwise disrupted. Since AIC-related measures are retained under both moderate- and higher-challenge, we propose a novel hypothesis that AIC sustains overall commitment regardless of challenge level, while disordered licking during HiChD mirrors the effects of dMPF inhibition. Thus, while AIC provides overall drive despite challenge, the ability to act is ultimately determined within the dMPF.

Relaxation Effect of Nature Sound Exposure on Gambling Disorder Patients: A Crossover Study

Objective: Gambling disorder (GD) has been associated with economic, social, mental, and physical problems. Alternative leisure activities or stress-relieving activities have been adopted as part of GD treatment. Moreover, it has been proven that activities utilizing the natural environment, such as shinrin-yoku, have a relaxing effect on healthy people. In this study, we examined the physiological and psychological responses of patients with GD to determine whether nature therapy could reduce their stress responses. Design: This study included 22 Japanese male participants who were found to be pathological gamblers, with a South Oaks Gambling Screen score of ≤5. We exposed the participants to the digital nature sounds of insects and city sounds of a scramble intersection. The nature and city sounds were presented in a counterbalanced order. Outcome measures: A two-channel near-infrared spectroscopy system was used to measure the changes in oxyhemoglobin (oxy-Hb) concentrations in the bilateral prefrontal cortex. The heart rate variability was measured to evaluate the autonomic nervous activity. Subjective evaluation was performed using the modified version of the semantic differential method and the Profiles of Mood States, Second Edition (POMS2). Results: The oxy-Hb level in the bilateral prefrontal cortex significantly decreased. No significant difference in the high-frequency (HF) and low-frequency/HF ratio was observed. The subjective evaluation indicated that the participants experienced increased comfort and relaxation and had more natural feelings. Nature sounds significantly decreased the POMS2 negative emotion subscale and total mood disturbance scores and increased the positive emotion subscale scores. Nature-based stimulus exposure induces physiological relaxation and other positive effects among individuals even with GD. Conclusion: Exposure to nature-based sounds induces physiological relaxation and other positive responses among individuals with GD. In patients with GD, nature sounds produce the same relaxation response as in healthy individuals. (Umin.ac.jp under registration number: UMIN000042368).

Opioid withdrawal: role in addiction and neural mechanisms

Withdrawal from opioids involves a negative affective state that promotes maintenance of drug-seeking behavior and relapse. As such, understanding the neurobiological mechanisms underlying withdrawal from opioid drugs is critical as scientists and clinicians seek to develop new treatments and therapies. In this review, we focus on the neural systems known to mediate the affective and somatic signs and symptoms of opioid withdrawal, including the mesolimbic dopaminergic system, basolateral amygdala, extended amygdala, and brain and hormonal stress systems. Evidence from preclinical studies suggests that these systems are altered following opioid exposure and that these changes mediate behavioral signs of negative affect such as aversion and anxiety during withdrawal. Adaptations in these systems also parallel the behavioral and psychological features of opioid use disorder (OUD), highlighting the important role of withdrawal in the development of addictive behavior. Implications for relapse and treatment are discussed as well as promising avenues for future research, with the hope of promoting continued progress toward characterizing neural contributors to opioid withdrawal and compulsive opioid use.

Health Outcomes by Neighborhood (HON): Effects of Neighborhood, Social Instability, and Health Factors on 12-Month Trajectories of Substance-Use Disorder Symptoms

BACKGROUND

Previous studies have shown that environment and health can influence drug use trajectories and the effects of substance use disorder (SUD) treatments. We hypothesized that trajectories of drug use-related problems, based on changes in DSM-5 symptoms, would vary by type(s) of drugs used, health factors, and neighborhood characteristics.

METHODS

We assessed mental and physical health, stress, social instability, neighborhood characteristics (disorderliness and home value), and DSM-5 symptom counts at two study visits, 12 months apart, in a community sample (baseline N = 735) in Baltimore, MD. Three prominent categories of drug-use trajectory were identified with K-means cluster analysis of symptom counts: Persistent (4 or more symptoms at both visits or at Visit 2), Improved (decrease from 4 or more symptoms at Visit 1 to 3 or fewer symptoms at Visit 2), and Low-Stable (3 or fewer symptoms at both visits). Baseline health and neighborhood measures were tested as predictors of trajectory in mediation and moderation models.

RESULTS

Among people with current opioid- and/or stimulant-use, odds of an Improved trajectory were (1) decreased with neighborhood disorder and social instability, or (2) increased with home value and social instability. Odds of a Low-Stable trajectory were decreased by social instability and stress but increased in those who were older or self-identified as white.

CONCLUSIONS

Trajectories of drug use-related problems are influenced by sociodemographic variables, neighborhood factors, and health. Assessing DSM-5 symptom counts as an outcome measure may be valuable in monitoring or predicting long-term trajectories and treatment effectiveness.

Twisted memories: Addiction-related engrams are strengthened by desire thinking

Associative learning plays a central role in addiction by reinforcing associations between environmental cues and addiction-related information. Unsupervised learning models posit that memories are adjusted based on how strongly these representations are coactivated during the retrieval process. From a different perspective, clinical models of addiction posit that the escalation and persistence of craving may depend on desire thinking, a thinking style orienting to prefigure information about positive addiction-related experiences. In the present work, we tested the main hypothesis that desire thinking is a key factor in the strengthening of addiction-related associations. A group of adult smoking volunteers (N = 26) engaged in a period of desire thinking before performing an associative learning task in which neutral words (cues) were shown along with images (smoking-related vs. neutral context) at different frequencies. Two retrieval tests were administered, one immediately after encoding and the other after 24 h, to test how the recall of associations changed as a function of retention interval. Two control groups, smokers (N = 21) and non-smokers (N = 22), performed a similar procedure, with a neutral imagination task replacing desire thinking. Participants who engaged in desire thinking increased their performance from the first to the second retrieval test only for the most frequent smoking-related associations. Crucially, this selective effect was not observed in the two control groups. These results provide behavioral evidence in support of the idea that desire thinking plays a role in strengthening addiction-related associations. Thus, this thinking process may be considered a target for reconsolidation-based conceptualizations of, and treatments for, addiction.

Animal models of compulsion alcohol drinking: Why we love quinine-resistant intake and what we learned from it

Alcohol Use Disorder (AUD) ranks among the most prevalent mental disorders, extracting ~$250 billion/year in the US alone and producing myriad medical and social harms. Also, the number of deaths related to problem drinking has been increasing dramatically. Compulsive alcohol drinking, characterized by intake that persists despite negative consequences, can be particularly important and a major obstacle to treatment. With the number of people suffering from AUD increasing during the past years, there is a critical need to understand the neurobiology related to compulsive drives for alcohol, as well as the development of novel AUD pharmacological therapies. Here we discuss rodent compulsion-like alcohol drinking (CLAD) models, focusing on the two most widely used adverse stimuli to model rodent compulsion-like responding, quinine adulteration of alcohol and footshook-resistant alcohol intake. For both cases, the goal is to uncover behavior patterns and brain circuits that underlie drive for alcohol even in the face of negative consequences. We discuss caveats, benefits, and potential brain mechanisms, of models for consequence-resistant responding for alcohol more generally, and especially highlight some advantages of quinine-resistance over footshook-resistance. Further, since this review contributes to a Special issue focused on Molecular Aspects of Compulsive Drug Use, we discuss our new findings showing how the noradrenergic system is related to CLAD responding. In particular, we comment on the importance of α1 and β adrenergic receptors (ARs) as potential targets for treating AUD.

Reframing caring for parents who struggle with substance-use disorders

Nancy Suchman and the colleagues she influenced have produced ground-breaking and attitude-challenging work in understanding how parenting and substance use come together. Dr Suchman and her colleagues make the claim that there is nothing about a substance-use disorder that precludes effective and sensitive caring for children especially with interventions that focus on the parent-child relationship. Suchman's legacy is to highlight how substance use as an illness pulls individuals away from important, caring relationships and limits their giving themselves to those relationships. Restoring the salience of caring relationships and of the individual's ability to care may be as impactful on their substance use as a strict focus on the reduction of drug use and achieving abstinence.

Sex differences in neural responses to stress and drug cues predicts future drug use in individuals with substance use disorder

BACKGROUND

Substance use disorders (SUDs) are chronically recurring illnesses, where stress and drug cues significantly increase drug craving and risk of drug use recurrence. This study examined sex differences in functional magnetic resonance imaging (fMRI) brain responses to stress and drug cue exposure and assessed their prospective association with future drug use post-treatment.

METHODS

Inpatient, treatment engaged men (N = 46) and women (N = 26) with SUDs, including alcohol, cocaine and/or cannabis use disorders, participated in an fMRI scan that assessed subjective (anxiety, drug craving), heart rate and neural responses to brief individualized script-driven imagery of stress, drug, and neutral-relaxing trials. Prospective follow-up interviews post-treatment assessed future drug use recurrence over 90 days.

RESULTS

During fMRI, stress and drug versus neutral cue exposure led to increased anxiety, heart rate and craving responses (p's < 0.004) in both men and women, but greater drug cue-induced anxiety (p < .017) and higher drug use days during follow-up (p < .006) in women relative to men. In whole brain analyses of stress and drug cues (p < .05 FWE corrected), and in whole brain correlation (p < .05, FWE corrected) with drug use days, significant sex differences revealed drug cue-related striatal hyperactivation (caudate, putamen) in men, but drug cue-related cortico-limbic (insula and dorsolateral prefrontal cortex) hypoactivation and stress-related hypoactivation in the ventromedial prefrontal cortex (VmPFC) in women; and these were significantly associated with higher future drug use days.

CONCLUSIONS

Findings indicate sex-specific pathophysiology of SUD recurrence and support the need for differential treatment development for men and women with SUD to improve drug use outcomes.

Examining the structural equation modeling between intrinsic-motivation, emotion regulation and AHDH: the mediating role of problem-solving, time-management, and behavioral-inhibition

Although Executive Functions has been considered as the main correlation of ADHD few studies have examined the effect of EFs on ADHD symptoms, in the samples with ADHD. This study aimed to examine the structure of EFs on ADHD students in a hypothesized model. After careful screening of ADHD among 1368 university students (with stratified and multistage cluster sampling), out of them, 211 students with ADHD diagnosis were selected purposefully. They received scales on their emotion regulation, motivation, adult ADHD, deficits in EFs, and diagnostic interview. Emotion regulation and intrinsic motivation were considered as input; behavioral-inhibition, time-management, and problem-solving were the mediators and ADHD subscales were as the output variables. Results showed that the model adequately fit the data. The model fit indices were χ2 = 27.081, df = 1, CFI = 0.99, GFI = 0.97, and PGFI = 0.02. The direct effects of intrinsic-motivation and emotion-regulation on all three mediators and indirect effects of them to ADHD subscales were significant. Based on the results, time-management mediated the relationship between motivation and emotion regulation and ADHD. Among EFs, emotion-regulation and intrinsic-motivation had fundamental influence to other aspects of EFs factors such as behavioral-inhibition, time-management, problem-solving, and attention deficit/hyperactivity disorder.

Correlation between abnormal brain network activity and electroencephalogram microstates on exposure to smoking-related cues

BACKGROUND

Research into neural mechanisms underlying cue-induced cigarette craving has attracted considerable attention for its significant role in treatments. However, there is little understanding about the effects of exposure to smoking-related cues on electroencephalogram (EEG) microstates of smokers, which can reflect abnormal brain network activity in several psychiatric disorders.

AIMS

To explore whether abnormal brain network activity in smokers on exposure to smoking-related cues would be captured by EEG microstates.

METHOD

Forty smokers were exposed to smoking and neutral imagery conditions (cues) during EEG recording. Behavioural data and parameters for microstate topographies associated with the auditory (A), visual (B), salience and memory (C) and dorsal attention networks (D) were compared between conditions. Correlations between microstate parameters and cigarette craving as well as nicotine addiction characteristics were also analysed.

RESULTS

The smoking condition elicited a significant increase in the duration of microstate classes B and C and in the duration and contribution of class D compared with the neutral condition. A significant positive correlation between the increased duration of class C (smoking minus neutral) and increased craving ratings was observed, which was fully mediated by increased posterior alpha power. The increased duration and contribution of class D were both positively correlated with years of smoking.

CONCLUSIONS

Our results indicate that smokers showed abnormal EEG microstates when exposed to smoking-related cues compared with neutral cues. Importantly, microstate class C (duration) might be a biomarker of cue-induced cigarette craving, and class D (duration and contribution) might reflect the relationship between cue-elicited activation of the dorsal attention network and years of smoking.

Effects of neuromodulation on cognitive and emotional responses to psychosocial stressors in healthy humans

Physiological and psychological stressors can exert wide-ranging effects on the human brain and behavior. Research has improved understanding of how the sympatho-adreno-medullary (SAM) and hypothalamic-pituitary-adrenocortical (HPA) axes respond to stressors and the differential responses that occur depending on stressor type. Although the physiological function of SAM and HPA responses is to promote survival and safety, exaggerated psychobiological reactivity can occur in psychiatric disorders. Exaggerated reactivity may occur more for certain types of stressors, specifically, psychosocial stressors. Understanding stressor effects and how the body regulates these responses can provide insight into ways that psychobiological reactivity can be modulated. Non-invasive neuromodulation is one way that responding to stressors may be altered; research into these interventions may provide further insights into the brain circuits that modulate stress reactivity. This review focuses on the effects of acute psychosocial stressors and how neuromodulation might be effective in altering stress reactivity. Although considerable research into stress interventions focuses on treating pathology, it is imperative to first understand these mechanisms in non-clinical populations; therefore, this review will emphasize populations with no known pathology and consider how these results may translate to those with psychiatric pathologies.

Towards Device Agnostic Detection of Stress and Craving in Patients with Substance Use Disorder

Novel technologies have great potential to improve the treatment of individuals with substance use disorder (SUD) and to reduce the current high rate of relapse (i.e. return to drug use). Wearable sensor-based systems that continuously measure physiology can provide information about behavior and opportunities for real-time interventions. We have previously developed an mHealth system which includes a wearable sensor, a mobile phone app, and a cloud-based server with embedded machine learning algorithms which detect stress and craving. The system functions as a just-in-time intervention tool to help patients de-escalate and as a tool for clinicians to tailor treatment based on stress and craving patterns observed. However, in our pilot work we found that to deploy the system to diverse socioeconomic populations and to increase usability, the system must be able to work efficiently with cost-effective and popular commercial wearable devices. To make the system device agnostic, methods to transform the data from a commercially available wearable for use in algorithms developed from research grade wearable sensor are proposed. The accuracy of these transformations in detecting stress and craving in individuals with SUD is further explored.

A critical perspective on updating drug memories through the integration of memory editing and brain stimulation

Addiction is a persistent, recurring condition characterized by repeated relapses despite the desire to control drug use or maintain sobriety. The attainment of abstinence is hindered by persistent maladaptive drug-associated memories, which drive drug-seeking and use behavior. This article examines the preliminary evidence supporting the combination of non-invasive brain stimulation (NIBS) techniques and memory editing (or reconsolidation) interventions as add-on forms of treatment for individuals with substance-related disorders (SUD). Studies have shown that NIBS can modestly reduce drug use and craving through improved cognitive control or other undetermined reasons. Memory reconsolidation, a process by which a previously consolidated memory trace can be made labile again, can potentially erase or significantly weaken SUD memories underpinning craving and the propensity for relapse. This approach conveys enthusiasm while also emphasizing the importance of managing boundary conditions and null results for interventions found on fear memory reconsolidation. Recent studies, which align with the state-dependency and activity-selectivity hypotheses, have shown that the combination of NIBS and behavioral interventions holds promise for treating SUD by reducing self-reported and physiological aspects of craving. Effective long-term outcomes for this procedure require better identification of critical memories, a deeper understanding of the brain mechanisms underlying SUD and memory reconsolidation and overcoming any boundary conditions of destabilized memories. This will enable the procedure to be personalized to the unique needs of individual patients.

Pregnenolone effects on provoked alcohol craving, anxiety, HPA axis, and autonomic arousal in individuals with alcohol use disorder

RATIONALE

Chronic alcohol intake down-regulates GABAergic transmission and reduces levels of neuroactive steroids. These changes are associated with greater stress dysregulation and high alcohol craving which in turn increases relapse risk.

OBJECTIVES

This study tested whether potentiation of the neurosteroid system with pregnenolone (PREG), a precursor to neuroactive steroids and known to increase GABAergic transmission, will normalize chronic alcohol-related stress adaptations in the hypothalamic-pituitary-adrenal (HPA) axis and autonomic responses and reduce alcohol craving to significantly impact relapse risk.

METHODS

Forty-three treatment-seeking individuals with alcohol use disorder (AUD) were randomized to placebo (PBO) or supraphysiologic pregnenolone doses of 300 mg or 500 mg treatment using a parallel-between subject design as part of a larger 8-week pilot clinical trial. In week 2, they participated in a 3-day laboratory experiment where on each day they self-administered the assigned study drug in the laboratory and were then exposed to 5-min personalized guided imagery provocation of stress, alcohol, or neutral/relaxing cues, one condition per day on separate days, in a random, counterbalanced order. Repeated assessments of alcohol craving, anxiety, HPA axis, heart rate (HR), systolic (SBP), and diastolic blood pressure (DBP) and serum pregnenolone levels were made on each day.

RESULTS

Pregnenolone levels were significantly increased in the PREG groups versus PBO. PREG treatment decreased stress- and alcohol cue- induced craving and dose-specifically reduced stress-induced anxiety in the 300 mg/day group. Both PREG doses compared to PBO also normalized CORT/ACTH and increased stress-induced HR, stress- and cue-induced SBP, and in the 300 mg PREG group cue-induced DBP responses relative to neutral condition.

CONCLUSIONS

Findings indicate that pregnenolone decreases stress- and alcohol cue-provoked craving and normalizes HPA axis and autonomic arousal in individuals with AUD, thereby supporting the need for further assessment of pregnenolone in the treatment of AUD.

Cognitive, Emotional, Behavioral and Physiological Evaluation of the Relationship Between Brain and Gut Microbiota

The aim of this study is to examine the effect of gut microbiota on brain functions, mood and psychiatric disorders such as depression, anxiety and behavioral addictions, neurotransmitter levels, cognitive processes such as self-control, decision making and delayed gratification. In this context, the relevant literature was reviewed and the findings were evaluated. The relationships of the bidirectional communication between the brain-gut axis with cognitive, emotional, behavioral and physiological processes were explained with a diagram. As a result, although more research is needed on this subject, it has been observed that the brain-gut axis is bidirectionally established through neural, stress, endocrine and immune systems. In this bidirectional communication process, there are interactions in the context of cognitive, emotional, behavioral and other physiological factors. These factors both individually enter into bidirectional relationships with the brain and gut microbiota and are affected by the bidirectional communication between the brain and gut.

Pregnenolone Reduces Stress-Induced Craving, Anxiety, and Autonomic Arousal in Individuals with Cocaine Use Disorder

Chronic cocaine use leads to adaptations in stress biology and in neuroactive steroid system. These adaptations are associated with high cocaine craving and increased relapse risk. This study tested whether potentiation of the neuroactive steroid system with the precursor pregnenolone (PREG) affects stress- and cue-induced cocaine craving, anxiety and autonomic response in individuals with cocaine use disorder (CUD). Thirty treatment-seeking individuals (21 Male, 9 Female) with CUD were randomized to placebo (PBO) or supraphysiologic PREG doses of 300 mg or 500 mg per day for 8 weeks. After 2 weeks of treatment, participants were exposed to 5-min personalized guided imagery provocation of stress, cocaine, or neutral/relaxing cues in a 3-day experiment, one condition per day on separate days, in a random, counterbalanced order. Repeated assessment of cocaine craving, anxiety, heart rate (HR), systolic (SBP) and diastolic blood pressure (DBP) were assessed on each day. PREG significantly increased pregnenolone levels compared to PBO. Both PREG doses decreased stress- and cocaine cue-induced craving and reduced both stress- and cue-induced anxiety only in the 500 mg/day group. The 500 mg/day PREG group also displayed decreased stress-induced HR, SBP and DBP. Findings indicate that pregnenolone decreases stress- and cocaine cue-provoked craving and anxiety and reduces stress-induced autonomic arousal in individuals with CUD.

Selective D3 receptor antagonism modulates neural response during negative emotional processing in substance dependence

Introduction

Negative affective states contribute to the chronic-relapsing nature of addiction. Mesolimbic dopamine D3 receptors are well placed to modulate emotion and are dysregulated in substance dependence. Selective antagonists might restore dopaminergic hypofunction, thus representing a potential treatment target. We investigated the effects of selective D3 antagonist, GSK598809, on the neural response to negative emotional processing in substance dependent individuals and healthy controls.

Methodology

Functional MRI BOLD response was assessed during an evocative image task, 2 h following acute administration of GSK598809 (60 mg) or placebo in a multi-site, double-blind, pseudo-randomised, cross-over design. Abstinent drug dependent individuals (DD, n = 36) comprising alcohol-only (AO, n = 19) and cocaine-alcohol polydrug (PD, n = 17) groups, and matched controls (n = 32) were presented with aversive and neutral images in a block design (contrast of interest: aversive > neutral). Whole-brain mixed-effects and a priori ROI analyses tested for group and drug effects, with identical models exploring subgroup effects.

Results

No group differences in task-related BOLD signal were identified between DD and controls. However, subgroup analysis revealed greater amygdala/insular BOLD signal in PD compared with AO groups. Following drug administration, GSK598809 increased BOLD response across HC and DD groups in thalamus, caudate, putamen, and pallidum, and reduced BOLD response in insular and opercular cortices relative to placebo. Multivariate analyses in a priori ROIs revealed differential effects of D3 antagonism according to subgroup in substantia nigra; GSK598809 increased BOLD response in AO and decreased response in PD groups.

Conclusion

Acute GSK598809 modulates the BOLD response to aversive image processing, providing evidence that D3 antagonism may impact emotional regulation. Enhanced BOLD response within D3-rich mesolimbic regions is consistent with its pharmacology and with attenuation of substance-related hypodopaminergic function. However, the lack of group differences in task-related BOLD response and the non-specific effect of GSK598809 between groups makes it difficult to ascertain whether D3 antagonism is likely to be normalising or restorative in our abstinent populations. The suggestion of differential D3 modulation between AO and PD subgroups is intriguing, raising the possibility of divergent treatment responses. Further study is needed to determine whether D3 antagonism should be recommended as a treatment target in substance dependence.

Ibudilast moderates the effect of mood on alcohol craving during stress exposure

Neuroinflammation is implicated in the development and maintenance of alcohol use disorder (AUD) and neuroimmune therapeutics show promise in treating AUD. Proinflammatory signaling contributes to progressive elevations in the dysfunction of mood and alcohol craving. The current study sought to examine potential biobehavioral mechanisms of neuroimmune modulation in AUD under experimental conditions. In a community sample of individuals with AUD who completed a placebo-controlled crossover trial of ibudilast, we tested the effect of ibudilast on the relationship between mood states and alcohol craving. Multilevel modeling analyses tested the hypothesis that ibudilast would moderate the effect of positive and negative mood states on alcohol craving during stress and cue exposures. Results revealed that after stress-induction, participants' feelings of depression and happiness were more strongly predictive of their craving for alcohol while taking ibudilast as compared with placebo (ps < .03). These results suggest that with neuroimmune modulation, positive and negative mood states may have a stronger influence on one's desire to drink, such that craving may be more mood dependent. No moderating effect of ibudilast on mood states and craving were observed after alcohol cue exposure. Given the potential of anti-inflammatory treatments to reduce depressive symptomatology, this strengthened relationship between mood and craving under ibudilast might reduce the likelihood of stress-related craving and subsequent drinking over time. Moreover, ibudilast may enhance the benefits of happiness, such that maintaining positive mood in the face of acute stress may attenuate craving. Future trials directly testing the clinical implications of these mechanistic findings are warranted. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Modeling Aversion Resistant Alcohol Intake in Indiana Alcohol-Preferring (P) Rats

With the substantial social and medical burden of addiction, there is considerable interest in understanding risk factors that increase the development of addiction. A key feature of alcohol use disorder (AUD) is compulsive alcohol (EtOH) drinking, where EtOH drinking becomes “inflexible” after chronic intake, and animals, such as humans with AUD, continue drinking despite aversive consequences. Further, since there is a heritable component to AUD risk, some work has focused on genetically-selected, EtOH-preferring rodents, which could help uncover critical mechanisms driving pathological intake. In this regard, aversion-resistant drinking (ARD) takes >1 month to develop in outbred Wistar rats (and perhaps Sardinian-P EtOH-preferring rats). However, ARD has received limited study in Indiana P-rats, which were selected for high EtOH preference and exhibit factors that could parallel human AUD (including front-loading and impulsivity). Here, we show that P-rats rapidly developed compulsion-like responses for EtOH; 0.4 g/L quinine in EtOH significantly reduced female and male intake on the first day of exposure but had no effect after one week of EtOH drinking (15% EtOH, 24 h free-choice paradigm). Further, after 4−5 weeks of EtOH drinking, males but not females showed resistance to even higher quinine (0.5 g/L). Thus, P-rats rapidly developed ARD for EtOH, but only males developed even stronger ARD with further intake. Finally, rats strongly reduced intake of quinine-adulterated water after 1 or 5 weeks of EtOH drinking, suggesting no changes in basic quinine sensitivity. Thus, modeling ARD in P-rats may provide insight into mechanisms underlying genetic predispositions for compulsive drinking and lead to new treatments for AUDs.

Irregular Autonomic Modulation Predicts Risky Drinking and Altered Ventromedial Prefrontal Cortex Response to Stress in Alcohol Use Disorder

AIMS

Autonomic dysfunction has been associated with risky drinking and alcohol use disorder (AUD). Although autonomic nervous system (ANS) activity has been attributed to the ventromedial prefrontal cortex (VmPFC)-limbic-striatal regions, the specific role of ANS disruption in AUD and its association with these regions remain unclear. Using functional magnetic resonance imaging (fMRI) and concurrent electrocardiogram (ECG), the current study examined neural correlates of ANS activity in AUD and its role in AUD pathology.

METHODS

Demographically matched 20 AUD patients and 20 social drinkers (SD) completed an fMRI task involving repeated exposure to stress, alcohol-cue and neutral-relaxing images in a block design. Based on the known VmPFC-limbic-striatal functions involved in emotions, reward and the ANS, we performed a regions of interest (ROI) analysis to examine the associations between ANS activity and neural responses in the VmPFC, amygdala, and ventral striatum.

RESULTS

Across conditions, AUD patients showed significantly higher levels of overall heart rate (HR) and approximate entropy (ApEn) compared to SD (Ps < 0.05). In all participants, increased HR was associated with greater drinking volume (P < 0.05). In addition, higher ApEn levels were associated with greater drinking volume (P < 0.05) and decreased right VmPFC response to stress (P < 0.05).

DISCUSSION

Our findings demonstrate ANS disruption in AUD indexed by high overall HR and ApEn. The association between ApEn and rVmPFC response suggests that ApEn may play a role in modulating drinking via interactions with neural regions of emotion regulation. These findings provide insight into patterns of ANS disruption and their relevance to AUD pathology.

Brain networks alterations in cocaine use and gambling disorders during emotion regulation

Background

Cocaine use disorder (CUD) and gambling disorder (GD) share clinical features and neural alterations, including emotion regulation deficits and dysfunctional activation in related networks. However, they also exhibit differential aspects, such as the neuroadaptive effects of long-term drug consumption in CUD as compared to GD. Neuroimaging research aimed at disentangling their shared and specific alterations can contribute to improve understanding of both disorders.

Methods

We compared CUD (N = 15), GD (N = 16) and healthy comparison (HC; N = 17) groups using a network-based approach for studying temporally coherent functional networks during functional magnetic resonance imaging (fMRI) of an emotion regulation task. We focused our analysis in limbic, ventral frontostriatal, dorsal attentional (DAN) and executive networks (FPN), given their involvement in emotion regulation and their alteration in CUD and GD. Correlations with measures of emotional experience and impulsivity (UPPS-P) were also performed.

Results

The limbic network was significantly decreased during emotional processing both for CUD and GD individuals compared to the HC group. Furthermore, GD participants compared to HC showed an increased activation in the ventral frontostriatal network during emotion regulation. Finally, networks' activation patterns were modulated by impulsivity traits.

Conclusions

Functional network analyses revealed both overlapping and unique effects of stimulant and gambling addictions on neural networks underpinning emotion regulation.

Effects of arousal modulation via resonance breathing on craving and affect in women with substance use disorder

BACKGROUND

Craving for alcohol and other drugs is a complex in-the-moment experience that involves within-person changes in physiological arousal and affect. We evaluated the utility of a just-in-time, self-administered resonance breathing smartphone application (app) to reduce craving and improve affect in women during outpatient treatment for substance use disorders (SUD).

METHODS

Women (N = 57) receiving outpatient addiction treatment were randomized to practice either cardiovascular resonance breathing (0.1 Hz/6 breaths per minute) or a sham (∼0.23 Hz/14 breaths per minute) in the face of urges over an 8-week intervention. Craving (Penn Alcohol Craving Scale) and affect (Positive and Negative Affect Scale) were collected weekly throughout the intervention. App data were uploaded weekly to assess frequency of use. Generalized Estimated Equations modeled craving and affect as a function of group randomization and app use frequency across the 8-week intervention.

FINDINGS

Higher levels of craving were associated with more frequent app use. The group X app use interaction was significant for craving. Frequent app use during the intervention phase was associated with lower craving levels in the resonance breathing group relative to the sham group over the 8-week intervention. There was no effect of app use frequency on affect measures.

CONCLUSIONS

Women assigned to practice sham breathing who used the intervention frequently experienced elevations in craving that are commonly reported during outpatient SUD treatment. Women assigned to resonance breathing who used the intervention frequently did not experience such increases. Resonance breathing may be protective against triggers in outpatient treatment. Physiological mechanisms are discussed.

Association Between Negative Affectivity and Craving in Substance-Related Disorders: A Systematic Review and Meta-analysis of Direct and Indirect Relationships

BACKGROUND

A sizeable literature highlighted that negative affectivity and craving are both known to be implicated in relapses.

OBJECTIVES

The present study synthetized the existing litterature to determine strength of the interaction between negative affectivity and craving for substance-related disorders including illicit drugs, alcohol and tobacco.

METHODS

We conducted a systematic review in accordance with PRISMA guidelines followed by a meta-analysis. Online computer databases PubMed, PsycINFO and Web of Science were searched systematically and thoroughly. Jamovi 1.8.1 Current version was used to conduct meta-analysis.

RESULTS

Thirty studies were included in the review, and 14 of these, including 2257 subjects, were used for meta-analysis. The raw correlation ranged from 0.17 to 0.58, which indicated weak to moderate association between negative affects and craving. In total, approximately 90% of the selection revealed a positive correlation between negative affects and craving. Alcohol and tobacco use disorders have received the most attention. Additionally, negative affectivity was often defined as a transient state rather than a stable personality trait.

CONCLUSIONS

In both of our meta-analyses and in the narratively reported studies, we found that negative affectivity is an important component related to craving, but individual differences in craving reactivity existed.

Exploring the Mechanism of Pathological Gaming in Adolescents: Focused on the Mediation Paths and Latent Group Comparison

Pathological gaming among adolescents has been reported to hamper the achievement of a balanced life and to threaten the development of social competencies. Despite the increasing social concerns on the adolescent users, however, the mechanism of gaming behavior of adolescents has not been sufficiently examined. This study explored the mechanism of pathological gaming among adolescents from 3-year longitudinal data of 778 Korean adolescent gamers, by analyzing the effects of negative affects (i.e., anxiety, loneliness, and academic stress) on the degree of pathological gaming through the mediation variables (i.e., aggression and self-control) based on the stimulus-organism-response (S-O-R) framework. Latent class analysis (LCA) was used to uncover potential risk groups, and through partial least squares-structural equation modeling (PLS-SEM) analysis, the mediation pathways to pathological gaming were compared between the risk group and the non-risk group. The results highlighted the key role of academic stress on the degree of pathological gaming. In the entire group, academic stress primarily increased pathological gaming through self-control. The mediation path of self-control was the most influential result in the risk group. Aggression was the key mediator between loneliness and pathological gaming in the non-risk group. The theoretical and practical implications of the results were discussed.

The Italian Version of Smartphone Addiction Inventory (SPAI-I) for Adolescents: Confirmatory Factor Analysis and Relation with Self-Control and Internalized-Externalized Symptoms

The increased smartphone use in adolescence has led clinicians and researchers to carry out in-depth studies on the matter. Adolescents seem to be at risk of smartphone addiction because they are yet to develop self-control in smartphone use. This psychometric study aimed at examining the levels of validity evidence for the Smartphone Addiction Inventory-Italian (SPAI-I) version for adults, among adolescents. Confirmatory Factor Analysis confirmed the factor structure of the SPAI-I version for adults among adolescents but not the exploratory factor structure for adults of the original Smartphone Addiction Inventory (SPAI). Convergent validity was assessed by examining the relationship between SPAI-I, self-control, and internalized and externalized problems. A total of 446 Italian adolescents (mean age = 16.04, SD = 1.72, 36.3% males) completed the Self-Restraint Subscale of the Adolescent Self-Consciousness and the Strengths and Difficulties Questionnaires—with a specific focus on the subscales of internalized and externalized problems. Present findings suggested that the SPAI-I version could be used to assess smartphone overuse among adolescents according to a multidimensional perspective.

Differential effects of recent versus past traumas on mood, social support, binge drinking, emotional eating and BMI, and on neural responses to acute stress

Traumatic stress is associated with risk of psychiatric and physical illnesses. However, the differential and separable effects of past versus recent traumas on maladaptive coping and neural responses are not known. We conducted two studies to assess separate and combined effects of cumulative recent and past trauma on health outcomes (study 1) and on neural responses to acute stress exposure in a subsample of individuals (study 2). Study 1 assessed a large cohort of 677 community adults cross-sectionally, and findings indicated that both high recent (within the last 12 months) and past trauma (prior to the last twelve months) were associated with more physical and psychological symptoms, including increased depression (all p's < .05). However, recent trauma alone was associated with higher problematic alcohol use, a greater maximum number of alcohol drinks consumed, greater emotional eating scores, higher state and trait anxiety scores, and poorer lifestyle habits (all p's < .05). Past trauma alone was associated with higher BMI, decreased social support, and a lower average cortisol relative to ACTH ratio (all p's < .02). Study 2 involving a functional brain scan on a subsample (N = 75) indicated greater recent trauma was associated with a hyperactive response in the ventromedial prefrontal cortex (VmPFC) to neutral-relaxed exposure, but blunted VmPFC response to acute stress exposure (p < .05: whole brain corrected-WBC). By contrast, high past trauma was associated with a hyper-sensitized neural response to stress in the cortico-limbic-striatal regions (p < .05, WBC) critical for reward and emotion processing. Together, these findings suggest differential neurobehavioral and health effects of cumulative past versus recent trauma exposure.

Immune treatments for alcohol use disorder: A translational framework

While the immune system is essential for survival, an excessive or prolonged inflammatory response, such as that resulting from sustained heavy alcohol use, can damage the host and contribute to psychiatric disorders. A growing body of literature indicates that the immune system plays a critical role in the development and maintenance of alcohol use disorder (AUD). As such, there is enthusiasm for treatments that can restore healthy levels of inflammation as a mechanism to reduce drinking and promote recovery. In this qualitative literature review, we provide a conceptual rationale for immune therapies and discuss progress in medications development for AUD focused on the immune system as a treatment target. This review is organized into sections based on primary signaling pathways targeted by the candidate therapies, namely: (a) toll-like receptors, (b) phosphodiesterase inhibitors, (c) peroxisome proliferator-activated receptors, (d) microglia and astrocytes, (e) other immune pharmacotherapies, and (f) behavioral therapies. As relevant within each section, we examine the basic biological mechanisms of each class of therapy and evaluate preclinical research testing the role of the therapy on mitigating alcohol-related behaviors in animal models. To the extent available, translational findings are reviewed with discussion of completed and ongoing randomized clinical trials and their findings to date. An applied and clinically focused approach is taken to identify the potential clinical applications of the various treatments reviewed. We conclude by delineating the most promising candidate treatments and discussing future directions by considering opportunities for immune treatment development and personalized medicine for AUD.

Cannabidiol as a treatment for craving and relapse in individuals with cocaine use disorder: a randomized placebo-controlled trial

BACKGROUND AND AIMS

Cocaine use disorder (CUD) is a significant public health concern for which no efficacious pharmacological interventions are available. Cannabidiol (CBD) has attracted considerable interest as a promising treatment for addiction. This study tested CBD efficacy for reducing craving and preventing relapse in people with CUD.

DESIGN

Single-site double-blind randomized controlled superiority trial comparing CBD with placebo.

SETTING AND PARTICIPANTS

Centre Hospitalier de l'Université de Montréal, Canada. Seventy-eight adults (14 women) with moderate to severe CUD participated.

INTERVENTION

Participants were randomly assigned (1 : 1) by stratified blocks to daily 800 mg CBD (n = 40) or placebo (n = 38). They first underwent an inpatient detoxification phase lasting 10 days. Those who completed this phase entered a 12-week outpatient follow-up.

MEASUREMENTS

Primary outcomes were drug-cue-induced craving during detoxication and time-to-cocaine relapse during subsequent outpatient treatment.

FINDINGS

During drug-cue exposure, craving scores [mean ± standard deviation (SD)] increased from baseline by 4.69 (2.89) versus 3.21 (2.78) points, respectively, in CBD (n = 36) and placebo (n = 28) participants [confidence interval (CI) = -0.33 to 3.04; P = 0.069; Bayes factor = 0.498]. All but three participants relapsed to cocaine by week 12 with similar risk for CBD (n = 34) and placebo (n = 27) participants (hazard ratio = 1.20, CI = 0.65-2.20, P = 0.51; Bayes factor = 0.152). CBD treatment was well tolerated and associated mainly with diarrhoea.

CONCLUSIONS

CBD did not reduce cocaine craving or relapse among people being treated for CUD.

Imagery of negative interpersonal experiences influence the neural mechanisms of social interaction

Negative interpersonal experiences are a key contributor to psychiatric disorders. While previous research has shown that negative interpersonal experiences influence social cognition, less is known about the effects on participation in social interactions and the underlying neurobiology. To address this, we developed a new naturalistic version of a gaze-contingent paradigm using real video sequences of gaze behaviour that respond to the participants' gaze in real-time in order to create a believable and continuous interactive social situation. Additionally, participants listened to two autobiographical audio-scripts that guided them to imagine a recent stressful and a relaxing situation and performed the gaze-based social interaction task before and after the presentation of either the stressful or the relaxing audio-script. Our results demonstrate that the social interaction task robustly recruits brain areas with known involvement in social cognition, namely the medial prefrontal cortex, bilateral temporoparietal junction, superior temporal sulcus as well as the precuneus. Imagery of negative interpersonal experiences compared to relaxing imagery led to a prolonged change in affective state and to increased brain responses during the subsequent social interaction paradigm in the temporoparietal junction, medial prefrontal cortex, anterior cingulate cortex, precuneus and inferior frontal gyrus. Taken together this study presents a new naturalistic social interaction paradigm suitable to study the neural mechanisms of social interaction and the results demonstrate that the imagery of negative interpersonal experiences affects social interaction on neural levels.

Loneliness and Mobile Phone Addiction Among Chinese College Students: The Mediating Roles of Boredom Proneness and Self-Control

INTRODUCTION

Mobile phones bring convenience to people's lives, but also affect their physical and mental health (especially in college students). Previous studies have revealed that mobile phone addiction is positively related to loneliness. This study further explored the mediating effects of boredom proneness and self-control on the relationship between loneliness and mobile phone addiction.

METHODS

A cross-sectional design was conducted in the present study. The investigation employed the Chinese version of the UCLA Loneliness Self-report Scale, Boredom Proneness Scale-Short Form, the Chinese version of the Self-control scale, and the Mobile Phone Addiction Index. Out of 1122 college students, 1078 completed the questionnaire survey and became our final subjects. PROCESS macro of SPSS 21 was used to conduct explore the mediating roles of boredom proneness and self-control in the relationship between loneliness and mobile phone addiction.

RESULTS

Loneliness, boredom proneness, and mobile phone addiction were significantly and positively correlated with each other, as well as significantly negatively correlated with self-control. Boredom proneness and self-control, when operating in parallel, partially mediated the relationship between loneliness and mobile phone addiction. By contrast, when occurring sequentially, they fully mediated the relationship between loneliness and mobile phone addiction.

CONCLUSION

Mobile phone addiction among lonely college students can be eliminated by exercising self-control and alleviating boredom proneness.

Beyond abstinence and relapse II: momentary relationships between stress, craving, and lapse within clusters of patients with similar patterns of drug use

RATIONALE

Given that many patients being treated for opioid-use disorder continue to use drugs, identifying clusters of patients who share similar patterns of use might provide insight into the disorder, the processes that affect it, and ways that treatment can be personalized.

OBJECTIVES AND METHODS

We applied hierarchical clustering to identify patterns of opioid and cocaine use in 309 participants being treated with methadone or buprenorphine (in a buprenorphine-naloxone formulation) for up to 16 weeks. A smartphone app was used to assess stress and craving at three random times per day over the course of the study.

RESULTS

Five basic patterns of use were identified: frequent opioid use, frequent cocaine use, frequent dual use (opioids and cocaine), sporadic use, and infrequent use. These patterns were differentially associated with medication (methadone vs. buprenorphine), race, age, drug-use history, drug-related problems prior to the study, stress-coping strategies, specific triggers of use events, and levels of cue exposure, craving, and negative mood. Craving tended to increase before use in all except those who used sporadically. Craving was sharply higher during the 90 min following moderate-to-severe stress in those with frequent use, but only moderately higher in those with infrequent or sporadic use.

CONCLUSIONS

People who share similar patterns of drug-use during treatment also tend to share similarities with respect to psychological processes that surround instances of use, such as stress-induced craving. Cluster analysis combined with smartphone-based experience sampling provides an effective strategy for studying how drug use is related to personal and environmental factors.

Social vulnerabilities for substance use: Stressors, socially toxic environments, and discrimination and racism

Applying a social determinants of health framework, this review brings attention to evidence from social sciences and neuroscience on the role of selected social factors in individual and population-level vulnerability to substance use and substance use disorders (SUDs). The understanding that social vulnerability to substance use and SUDs is multifaceted and occurs across different levels of influence (individual, interpersonal, community, and societal) is underscored. We propose that socially based stressors play a critical role in creating vulnerability to substance use and SUDs, and as such, deserve greater empirical attention to further understand how they "get under the skin." Current knowledge from social sciences and neuroscience on the relationships among vulnerability to substance use resulting from stressors, exposure to socially toxic childhood environments, and racism and discrimination are summarized and discussed, as are implications for future research, practice, and policy. Specifically, we propose using a top-down approach to the examination of known, yet often unexplored, relationships between vulnerability to substance use and SUDs, related inequities, and potential differential effects across demographic groups. Finally, research gaps and promising areas of research, practice, and policy focused on ameliorating social vulnerabilities associated with substance use and SUDs across the lifespan are presented. This article is part of the special issue on 'Vulnerabilities to Substance Abuse'.

Recent Perspectives on Sex Differences in Compulsion-Like and Binge Alcohol Drinking

Alcohol use disorder remains a substantial social, health, and economic problem and problem drinking levels in women have been increasing in recent years. Understanding whether and how the underlying mechanisms that drive drinking vary by sex is critical and could provide novel, more targeted therapeutic treatments. Here, we examine recent results from our laboratories and others which we believe provide useful insights into similarities and differences in alcohol drinking patterns across the sexes. Findings for binge intake and aversion-resistant, compulsion-like alcohol drinking are considered, since both are likely significant contributors to alcohol problems in humans. We also describe studies regarding mechanisms that may underlie sex differences in maladaptive alcohol drinking, with some focus on the importance of nucleus accumbens (NAcb) core and shell regions, several receptor types (dopamine, orexin, AMPA-type glutamate), and possible contributions of sex hormones. Finally, we discuss how stressors such as early life stress and anxiety-like states may interact with sex differences to contribute to alcohol drinking. Together, these findings underscore the importance and critical relevance of studying female and male mechanisms for alcohol and co-morbid conditions to gain a true and clinically useful understanding of addiction and neuropsychiatric mechanisms and treatment.

Remote memory of drug experiences coexists with cognitive decline and abnormal adult neurogenesis in an animal model of cocaine-altered cognition

Cocaine addiction is a chronic disorder in which the person loses control over drug use. The past memories of the stimuli associated with the drug are a relevant clinical problem, since they trigger compulsive drug-seeking and drug-taking habits. Furthermore, these persistent drug-related memories seemingly coexist with cognitive decline that predicts worse therapeutic output. Here, we use a new animal model of cocaine-altered cognition that allowed to observe these events in the same individual and study their relationship. Mice were chronically administered cocaine in a conditioned place preference (CPP) apparatus for 14 days, and control mice received saline. After 28 days of cocaine withdrawal, animals were tested for retrieval of remote drug-associated memory as well as for cognitive performance in a battery of tests, including novel object and place recognition and spatial memory. The cocaine-withdrawn mice showed persistent CPP memory while impaired in the cognitive tasks, displaying deficits in reference memory acquisition and working memory. However, the CPP expression was not associated with the defective cognitive performance, indicating that they were concomitant but independent occurrences. After completion of the experiment, adult hippocampal neurogenesis (AHN) was studied as a relevant neurobiological correlate due to its potential role in both learning and drug addiction. Results suggested a preserved basal AHN in the cocaine-withdrawn mice but an aberrant learning-induced regulation of these neurons. This paradigm may be useful to investigate maladaptive cognition in drug addiction as well as related therapies.

Effects of cortisol administration on craving during in vivo exposure in patients with alcohol use disorder

Alcohol-associated memories and craving play a crucial role in the development and maintenance of alcohol use disorder (AUD). As treatment options are limited in AUD, novel treatment strategies focus on the manipulation of alcohol-associated memories. The stress hormone cortisol affects various memory processes, and first clinical studies have shown that it inhibits the retrieval of disorder-specific memories and enhances extinction memory. This study aimed to investigate the effects of a single oral administration of cortisol on craving in patients with AUD during repeated in vivo exposure to alcohol pictures and the preferred alcoholic drink. In a double-blind, block-randomized, placebo-controlled cross-over design, 46 patients with AUD were treated with two sessions of in vivo exposure to alcohol. Cortisol (20 mg) or placebo was orally administered 1 h before each test day. Craving, stress, and cortisol were repeatedly measured during exposure sessions. Results show, that cortisol administration had distinct effects on craving depending on the severity of AUD and test day. While cortisol administration significantly enhanced craving during exposure on the first test day in patients with less severe AUD, it reduced craving in patients with more severe AUD. Independent of the cortisol administration, repeated in vivo exposure reduced craving from test day 1 to test day 2. In conclusion, adding cortisol to in vivo exposure might be a promising approach for reducing the strength of alcohol-associated memories and might promote the consolidation of extinction memory in patients with severe AUD. However, the differential effect of cortisol on craving depending on AUD severity cannot be conclusively explained and highlights the need for future studies elucidating the underlying mechanism.

Facebook Intrusion as a Mediator Between Positive Capital and General Distress: A Cross-Cultural Study

Background: Social networking sites (SNSs) play an important role in many aspects of life nowadays, and it seems to be crucial to explore their impact on human well-being and functioning. The main aim of the study was to examine the mediating role of Facebook intrusion between positive capital and general distress. Positive capital was considered as comprising self-esteem, ego-resiliency, and self-control, while general distress was seen as having three dimensions: depression, anxiety, and stress. Methods: The sample consisted of N = 4,495 participants (M = 22.96 years, SD = 5.46) from 14 countries: Australia, Cyprus, Greece, Hong Kong, Lithuania, New Zealand, Peru, Poland, Russia, Spain, Turkey, Ukraine, United Kingdom, and United States. We used the following methods: the Facebook Intrusion Questionnaire (FIQ), the Self-Esteem Scale (SES), the Brief Self-Control Scale (SCS), The Ego Resiliency Revised Scale and the Depression, Anxiety, and Stress Scale-21 (DASS-21). Results: We found that Facebook intrusion was a mediator between self-esteem and general distress and between self-control and general distress. Limitations: The present study was based on a cross-sectional study, and the measures used were self-report measures. The majority of the participants were recruited using convenience sampling. Conclusions: The present findings contribute to a better understanding on how the social media have impact on individual mental health. Implications for future studies are discussed.