Cue exposure therapy for the treatment of alcohol use disorders: A meta-analytic review

Disruption of relapse to cocaine and morphine seeking by LiCl-induced aversive counterconditioning following memory retrieval

Substance use disorder is conceptualized as a form of maladaptive learning, whereby drug-associated memories, elicited by the presence of stimuli related to drug contexts or cues, contribute to the persistent recurrence of craving and the reinstatement of drug-seeking behavior. Hence, use of pharmacology or non-pharmacology way to disrupt drug-related memory holds promise to prevent relapse. Several studies have shown that memories can be unstable and susceptible to modification during the retrieval reactivation phase, termed the "reconsolidation time window". In this study, we use the classical conditioned place preference (CPP) model to investigate the role of aversive counterconditioning on drug-related memories during reconsolidation. Specifically, we uncovered that reconditioning drug cues through counterconditioning with LiCl-induced aversive outcomes following drug memory retrieval reduces subsequent drug-seeking behavior. Notably, the recall of cocaine- or morphine-CPP was eliminated when LiCl-induced aversive counterconditioning was performed 10 min, but not 6 h (outside the reconsolidation time window) after cocaine or morphine memory retrieval. In addition, the effect of LiCl-induced aversive counterconditioning could last for about 14 days. These results suggest that aversive counterconditioning during the reconsolidation of cocaine or morphine memory can prevent the re-seeking of cocaine or morphine, presumably by updating or replacing cocaine or morphine memories with aversive information.

The Continuing Challenges of Studying Parallel Behaviours in Humans and Animal Models

The use of animal models continues to be essential for carrying out research into clinical phenomena, including addiction. However, the complexity of the clinical condition inevitably means that even the best animal models are inadequate, and this may go some way to account for the apparent failures of discoveries from animal models, including the identification of potential novel therapies, to translate to the clinic. We argue here that it is overambitious and misguided in the first place to attempt to model complex, multifacetted human disorders such as addiction in animals, and especially in rodents, and that all too frequently "validity" of such models is limited to superficial similarities, referred to as "face validity", that reflect quite different underlying phenomena and biological processes from the clinical situation. Instead, a more profitable approach is to identify (a) well-defined intermediate human behavioural phenotypes that reflect defined, limited aspects of, or contributors to, the human clinical disorder, and (b) to develop animal models that are homologous with those discrete human behavioural phenotypes in terms of psychological processes, and underlying neurobiological mechanisms. Examples of past and continuing weaknesses and suggestions for more limited approaches that may allow better homology between the test animal and human condition are made.

Virtual reality cue-exposure therapy in reducing cocaine craving: the Promoting Innovative COgnitive behavioral therapy for Cocaine use disorder (PICOC) study protocol for a randomized controlled trial

BACKGROUND

Cocaine craving is a central symptom of cocaine use disorders (CUD). Virtual reality cue-exposure therapy for craving (VRCET) allows more immersive, realistic, and controllable exposure than traditional non-VR cue-exposure therapy (CET), whose efficacy is limited in treating substance use disorders. The purpose of this study is to evaluate the efficacy and acceptability of VRCET, as a stand-alone and add-on intervention (i.e., combined with cognitive therapy), compared to a picture-based CET (PCET), in reducing self-reported cocaine craving in inpatients hospitalized for CUD.

METHODS

Fifty-four inpatients hospitalized for CUD will be randomized in one of two intensive 3-week treatment arms: 10 meetings/2-week treatment of VRCET plus 5 meetings/1-week treatment of memory-focused cognitive therapy (MFCT; experimental arm), or 15 meetings/3-week treatment of PCET (active control arm). The Craving Experience Questionnaire (CEQ - F & S) will be used to assess the primary outcome, i.e., the post-treatment decrease of self-reported cocaine craving frequency (within the past 2 weeks) and intensity scores (in VR exposure to cocaine cues). Secondary endpoints include urinary, physiological, and self-reported cocaine use-related measures. Assessments are scheduled at pretreatment, after 2 weeks of treatment (i.e., VRCET vs. PCET), post-treatment (3 weeks, i.e., VRCET + MFCT vs. PCET), and at 1-month follow-up. Acceptability will be evaluated via (i) the Spatial Presence for Immersive Environments - Cybersickness along VRCET and (ii) the Client Satisfaction Questionnaires after 2 weeks of treatment and post-treatment.

DISCUSSION

This study will be the first to evaluate the acceptability and efficacy of VRCET for CUD, as a psychotherapeutic add-on, to reduce both cocaine craving frequency and intensity. Additionally, this study will provide evidence about the specific interest of VRCET, compared to a non-VR-based CET, as a cue reactivity and exposure paradigm for treating substance use disorders.

TRIAL REGISTRATION

NCT05833529 [clinicaltrials.gov]. Prospectively registered on April 17, 2023.

Changes in dorsomedial striatum activity during expression of goal-directed vs. habit-like cue-induced cocaine seeking

A preclinical model of cue exposure therapy, cue extinction, reduces cue-induced cocaine seeking that is goal-directed but not habit-like. Goal-directed and habitual behaviors differentially rely on the dorsomedial striatum (DMS) and dorsolateral striatum (DLS), but the effects of cue extinction on dorsal striatal responses to cue-induced drug seeking are unknown. We used fiber photometry in rats trained to self-administer cocaine paired with an audiovisual cue to examine how dorsal striatal intracellular calcium and extracellular dopamine activity differs between goal-directed and habit-like cue-induced cocaine seeking and how it is impacted by cue extinction. After minimal fixed-ratio training, rats showed enhanced DMS and DLS calcium responses to cue-reinforced compared to unreinforced lever presses. After rats were trained on goal-promoting fixed ratio schedules or habit-promoting second-order schedules of reinforcement, different patterns of dorsal striatal calcium and dopamine responses to cue-reinforced lever presses emerged. Rats trained on habit-promoting second-order schedules showed reduced DMS calcium responses and enhanced DLS dopamine responses to cue-reinforced lever presses. Cue extinction reduced calcium responses during subsequent drug seeking in the DMS, but not in the DLS. Therefore, cue extinction may reduce goal-directed behavior through its effects on the DMS, whereas habit-like behavior and the DLS are unaffected.

Use of the overexpectation effect to reduce conditioned seeking behavior controlled by nicotine

Nicotine produces robust stimulus effects that can be conditioned to form associations with reinforcing nondrug stimuli. We examine how established associations to the nicotine stimulus may be weakened via the overexpectation effect. In two experiments, we separately conditioned sucrose associations to the interoceptive nicotine stimulus (0.4 mg/kg, SC) and to a "noisy" exteroceptive contextual stimulus (oscillating houselight and white noise) via the discriminated goal-tracking task. Thereafter, we presented additional sucrose pairings with the nicotine and noisy stimuli, now in compound. Testing of the conditioned goal-tracking evoked by the nicotine and noisy stimuli in isolation-before versus after compound conditioning (Experiment 1) or between treatment and control groups (Experiment 2)-demonstrated an attenuation of conditioned responding via the overexpectation effect. We suggest that applications of the overexpectation effect may provide some promise for treatments seeking to attenuate drug-evoked conditioned responses in situations where extinction-based interventions are not suitable.

Cigarette craving in virtual reality cue exposure in abstainers and relapsed smokers

Cue exposure therapy (CET) in substance-use disorders aims to reduce craving and ultimately relapse rates. Applying CET in virtual reality (VR) was proposed to increase its efficacy, as VR enables the presentation of social and environmental cues along with substance-related stimuli. However, limited success has been reported so far when applying VR-CET for smoking cessation. Understanding if effects of VR-CET differ between future abstainers and relapsing smokers may help to improve VR-CET. Data from 102 participants allocated to the intervention arm (VR-CET) of a recent RCT comparing VR-CET to relaxation in the context of smoking cessation was analyzed with respect to tolerability, presence, and craving during VR-CET. Cue exposure was conducted in four VR contexts (Loneliness/Rumination, Party, Stress, Café), each presented twice. Relapsed smokers compared to abstainers experienced higher craving during VR-CET and stronger craving responses especially during the Stress scenario. Furthermore, lower mean craving during VR-CET positively predicted abstinence at 6-month follow-up. Attempts to improve smoking cessation outcomes of VR-CET should aim to identify smokers who are more at risk of relapse based on high craving levels during VR-CET. Specifically measuring craving responses during social stress seems to be well suited to mark relapse. We propose to investigate individualized treatment approaches accordingly.

Cue-exposure treatment influences resting-state functional connectivity-a randomized controlled fMRI study in alcohol use disorder

RATIONALE

Cue-exposure therapy (CET) consists of exposing patients to the cause of their affliction in a controlled environment and after psychological preparation. Ever since it was conceived, it has been suggested as a treatment for different types of behavioural impairments, from anxiety disorders to substance abuse. In the field of addictive behaviour, many different findings have been shown regarding the effectiveness of this therapy.

OBJECTIVES

This study aims to examine the underlying neurobiological mechanisms of the effects of CET in patients with alcohol use disorder using resting-state functional magnetic resonance imaging (rs-fMRI).

METHODS

In a randomized, controlled study, we examined patients after inpatient detoxification as well as healthy controls. Patients underwent nine sessions of CET spaced over 3 weeks. Rs-fMRI was conducted before treatment and 3 weeks after treatment onset in patients, healthy controls received only one rs-fMRI measurement. The final participant sample with complete data included 35 patients in the CET group, 17 patients in the treatment-as-usual group, and 43 HCs.

RESULTS

Our results show differences in the Salience Network when comparing the CET group to the treatment-as-usual group (TAU). Functional connectivity between the anterior cingulate Cortex (ACC) and the insula was increased after CET, whereas it was decreased from ACC to the putamen and globus pallidus. Further, increased connectivity with the precuneus was found in the dorsal attention network after cue exposure treatment.

CONCLUSIONS

These findings suggest that cue exposure therapy changes the resting-state brain connectivity with additional effects to the standard psychotherapy treatment. Hence, our study results suggest why including CET in standard therapies might improve the preparation of patients in front of daily situations.

Virtual reality-assisted cognitive behavioral therapy for patients with alcohol use disorder: a randomized feasibility study

Introduction

Cognitive behavioral therapy (CBT) is an evidence-based treatment for alcohol use disorder (AUD). Exposure to high-risk situations in virtual reality (VR) has been suggested to have a potential therapeutical benefit, but no previous study has combined VR and CBT for AUD. We aimed to investigate the feasibility of using VR-simulated high-risk environments in CBT-based treatment of AUD.

Methods

We randomized ten treatment-seeking AUD-diagnosed individuals to three sessions of conventional CBT or VR-assisted CBT performed at two outpatient clinics in Denmark. In each session, patients randomized to VR-CBT were exposed to VR-simulations from a restaurant to induce authentic thoughts, emotions, physiological reactions, and craving for CBT purposes. The primary outcome measure was feasibility: Drop-out rate, psychological reactions, and simulator sickness. Secondary outcomes were assessment of preliminary short-term changes in alcohol consumption and craving from baseline to one-week and one-month follow-up. In addition, the study was conducted for training in operationalization of VR equipment, treatment manuals, and research questionnaires.

Results

The majority of patients completed all study visits (90%). VR induced authentic high-risk related thoughts, emotions, and physiological reactions that were considered relevant for CBT by patients and therapists. Four of five patients randomized to VR-CBT experienced cravings during VR simulations, and most of these patients (3/5) experienced mild simulator sickness during VR exposure. The preliminary data showed that patients receiving VR-CBT had more reduction in alcohol consumption than patients receiving conventional CBT at one week- (median 94% vs. 72%) and one-month follow-up (median 98% vs. 55%). Similar results were found regarding changes in cravings.

Conclusion

We demonstrated VR-CBT to be a feasible intervention for patients with AUD which supports continued investigations in a larger randomized clinical trial evaluating the efficacy of VR-CBT.

Clinical trial registration

https://www.clinicaltrials.gov/study/NCT04990765?cond=addiction%20CRAVR&rank=2, identifier NCT05042180.

Effects of virtual reality-based cue exposure therapy on craving and physiological responses in alcohol-dependent patients-a randomised controlled trial

BACKGROUND

Cue exposure therapy is used to treat alcohol dependence. However, its effectiveness is controversial due to the limitations of the clinical treatment setting. Virtual reality technology may improve the therapeutic effect. The aim of this study is to explore whether virtual reality-based cue exposure therapy can reduce the psychological craving and physiological responses of patients with alcohol dependence.

METHODS

Forty-four male alcohol-dependent patients were recruited and divided into the study group (n = 23) and the control group (n = 21) according to a random number table. The control group received only conventional clinical treatment for alcohol dependence. The study group received conventional clinical treatment with the addition of VR cue exposure (treatment). The primary outcome was to assess psychological craving and physiological responses to cues of patients before and after treatment.

RESULTS

After virtual reality-based cue exposure therapy, the changes in VAS and heart rate before and after cue exposure in the study group were significantly lower than those in the control group (P < 0.05), while the changes in skin conductance and respiration between the study group and the control group were not significantly different (P > 0.05). The changes in VAS and heart rate before and after cue exposure in the study group were significantly lower than those before treatment (P < 0.05), while the changes in skin conductance and respiration were not significantly different from those before treatment (P > 0.05). The changes in VAS, heart rate, skin conductance and respiration before and after cue exposure in the control group were not significantly different from those before treatment (P > 0.05).

CONCLUSION

Virtual reality-based cue exposure therapy can reduce the psychological craving and part of the physiological responses of alcohol-dependent patients during cue exposure in the short term and may be helpful in the treatment of alcohol dependence.

TRIAL REGISTRATION

The study protocol was registered at the China Clinical Trial Registry on 26/02/2021 ( www.chictr.org.cn ; ChiCTR ID: ChiCTR2100043680).

Drug memory reconsolidation: from molecular mechanisms to the clinical context

Since its rediscovery at the beginning of the 21st Century, memory reconsolidation has been proposed to be a therapeutic target for reducing the impact of emotional memories that can go awry in mental health disorders such as drug addiction (substance use disorder, SUD). Addiction can be conceptualised as a disorder of learning and memory, in which both pavlovian and instrumental learning systems become hijacked into supporting drug-seeking and drug-taking behaviours. The past two decades of research have characterised the details of the molecular pathways supporting the reconsolidation of pavlovian cue-drug memories, with more recent work indicating that the reconsolidation of instrumental drug-seeking memories also relies upon similar mechanisms. This narrative review considers what is known about the mechanisms underlying the reconsolidation of pavlovian and instrumental memories associated with drug use, how these approaches have translated to experimental medicine studies, and the challenges and opportunities for the clinical use of reconsolidation-based therapies.

Extinction in multiple contexts reduces the return of extinguished responses: A multilevel meta-analysis

Extinguished responses have been shown to reappear under several circumstances, and this reappearance is considered to model behaviors such as relapse after exposure therapy. Conducting extinction in multiple contexts has been explored as a technique to decrease the recovery of extinguished responses. The present meta-analysis aimed to examine whether extinction in multiple contexts can consistently reduce the recovery of extinguished responses. After searching in several databases, experiments were included in the analysis if they presented extinction in multiple contexts, an experimental design, and an adequate statistical report. Cohen's d was obtained for each critical comparison and weighted to obtain the sample's average weighted effect size. Analyses were then performed using a multilevel meta-analytic approach. Twenty-five studies were included, with a total sample of 37 experiments or critical comparisons. The analyses showed a large effect size for the sample, moderated by the length of conditioned stimulus exposure, type of experimental subject, and type of recovery. The robust effect of extinction in multiple contexts on relapse should encourage clinicians to consider extinction in multiple contexts as a useful technique in therapy and research.

An explorative single-arm clinical study to assess craving in patients with alcohol use disorder using Virtual Reality exposure (CRAVE)-study protocol

BACKGROUND

Alcohol use disorder (AUD) belongs to the most burdensome clinical disorders worldwide. Current treatment approaches yield unsatisfactory long-term effects with relapse rates up to 85%. Craving for alcohol is a major predictor for relapse and can be intentionally induced via cue exposure in real life as well as in Virtual Reality (VR). The induction and habituation of craving via conditioned cues as well as extinction learning is used in Cue Exposure Therapy (CET), a long-known but rarely used strategy in Cognitive Behavioral Therapy (CBT) of AUD. VR scenarios with alcohol related cues offer several advantages over real life scenarios and are within the focus of current efforts to develop new treatment options. As a first step, we aim to analyze if the VR scenarios elicit a transient change in craving levels and if this is measurable via subjective and psychophysiological parameters.

METHODS

A single-arm clinical study will be conducted including n = 60 patients with AUD. Data on severity of AUD and craving, comorbidities, demographics, side effects and the feeling of presence in VR will be assessed. Patients will use a head-mounted display (HMD) to immerse themselves into three different scenarios (neutral vs. two target situations: a living room and a bar) while heart rate, heart rate variability, pupillometry and electrodermal activity will be measured continuously. Subjective craving levels will be assessed before, during and after the VR session.

DISCUSSION

Results of this study will yield insight into the induction of alcohol craving in VR cue exposure paradigms and its measurement via subjective and psychophysiological parameters. This might be an important step in the development of innovative therapeutic approaches in the treatment of patients with AUD.

TRIAL REGISTRATION

This study was approved by the Charité-Universitätsmedizin Berlin Institutional Review Board (EA1/190/22, 23.05.2023). It was registered on ClinicalTrials.gov (NCT05861843).

Effectiveness of Reducing Craving in Alcohol Use Disorder Using a Serious Game (SALIENCE): Randomized Controlled Trial

BACKGROUND

Alcohol use disorder (AUD) has become a major global health problem. Therapy for this condition is still a great challenge. Recently, it has become increasingly evident that computer-based training is a valuable addition to the treatment of addictive disorders.

OBJECTIVE

This study aims to evaluate the web-based serious game SALIENCE (Stop Alcohol in Everyday Life-New Choices and Evaluations) as an add-on therapy for AUD. It combines the cue-exposure therapy approach with elements of decision-making training, enhanced by interactive panoramic images. The effects of SALIENCE training on levels of craving, attention, and cognitive bias are investigated.

METHODS

In a randomized controlled trial, 62 participants with AUD undergoing 3 weeks of an extended alcohol detoxification program were randomly allocated to an intervention and a control group. A total of 49 individuals (mean age 44.04 y; 17/49, 35% female) completed all sessions and were included in the analysis. Only pretreatment data were available from the other 13 patients. Participants answered questionnaires related to alcohol consumption and craving and completed neuropsychological tasks at the beginning of the study and 2 weeks later to evaluate levels of attention and cognitive biases. During the 2-week period, 27 of the participants additionally performed the SALIENCE training for 30 minutes 3 times a week, for a total of 6 sessions.

RESULTS

We observed a significant decrease in craving in both groups: the control group (mean 15.59, SD 8.02 on the first examination day vs mean 13.18, SD 8.38 on the second examination day) and the intervention group (mean 15.19, SD 6.71 on the first examination day vs mean 13.30, SD 8.47 on the second examination day; F1,47=4.31; P=.04), whereas the interaction effect was not statistically significant (F1,47=0.06; P=.80). Results of the multiple linear regression controlling for individual differences between participants indicated a significantly greater decrease in craving (β=4.12; t36=2.34; P=.03) with the SALIENCE intervention. Participants with lower drinking in negative situations reduced their craving (β=.38; t36=3.01; P=.005) more than people with higher drinking in negative situations.

CONCLUSIONS

The general effectiveness of SALIENCE training as an add-on therapy in reducing alcohol craving was not confirmed. Nevertheless, taking into account individual differences (gender, duration of dependence, stress, anxiety, and drinking behavior in different situations), it was shown that SALIENCE training resulted in a larger reduction in craving than without. Notably, individuals who rarely consume alcohol due to negative affect profited the most from SALIENCE training. In addition to the beneficial effect of SALIENCE training, these findings highlight the relevance of individualized therapy for AUD, adapted to personal circumstances such as drinking motivation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03765476; https://clinicaltrials.gov/show/NCT03765476.

Be more mindful: Targeting addictive responses by integrating mindfulness with cognitive bias modification or cue exposure interventions

This review provides an overview of the most prominent neurocognitive effects of cognitive bias modification (CBM), cue-exposure therapy and mindfulness interventions for targeting addictive responses. It highlights the key insights that have stemmed from cognitive neuroscience and brain imaging research and combines these with insights from behavioural science in building a conceptual model integrating mindfulness with response-focused CBM or cue-exposure interventions. This furthers our understanding of whether and how mindfulness strategies may i) facilitate or add to the induced response-focused effects decreasing cue-induced craving, and ii) further weaken the link between craving and addictive responses. Specifically, awareness/monitoring may facilitate, and decentering may add to, response-focused effects. Combined awareness acceptance strategies may also diminish the craving-addiction link. The conceptual model presented in this review provides a specific theoretical framework to deepen our understanding of how mindfulness strategies and CBM or cue-exposure interventions can be combined to greatest effect. This is important in both suggesting a roadmap for future research, and for the further development of clinical interventions.

The efficacy of virtual reality exposure therapy for the treatment of alcohol use disorder among adult males: a randomized controlled trial comparing with acceptance and commitment therapy and treatment as usual

Background

This multicenter, three-armed, parallel, single-blind randomized controlled trial (RCT) primarily aims to compare the efficacy of virtual reality exposure therapy (VRET) with that of acceptance and commitment therapy (ACT) and treatment as usual (TAU) to depreciate the degree of alcohol craving among alcohol use disorder patients who have undergone in-patient detoxification across four timelines (t0 = baseline prior to intervention, t1 = 4 weeks after baseline, t2 = 12 weeks after baseline, and t3 = 24 weeks after baseline). The secondary aims of this RCT are to compare the efficacy of VRET with that of ACT and TAU to alleviate the severity of alcohol use disorder, dissipate comorbid depressive and anxiety symptoms, and normalize event-related potential (ERP) in electroencephalogram (EEG) monitoring across the four timelines.

Methods

Initially, after 2 weeks of in-patient detoxification, 120 patients with alcohol use disorder will be randomized into three groups (VRET, ACT, and TAU control groups) via stratified permuted block randomization in a 1:1:1 ratio. Baseline assessment (t0) commences, whereby all the participants will be administered with sociodemographic, clinical, and alcohol use characteristics questionnaire, such as Alcohol Use Disorder Identification Test (AUDIT), Penn Alcohol Craving Scale (PACS), Hamilton Anxiety Rating Scale (HAM-A), and Hamilton Depression Rating Scale (HAM-D), while event-related potential (ERP) detection in electroencephalogram (EEG) will also be carried out. Then, 4 weeks of VRET, ACT, and non-therapeutic supportive activities will be conducted in the three respective groups. For the subsequent three assessment timelines (t1, t2, and t3), the alcohol use characteristic questionnaire, such as AUDIT, PACS, HAM-D, HAM-A, and ERP monitoring, will be re-administered to all participants.

Discussion

As data on the effects of non-pharmacological interventions, such as VRET and ACT, on the treatment of alcohol craving and preventing relapse in alcohol use disorder are lacking, this RCT fills the research gap by providing these important data to treating clinicians. If proven efficacious, the efficacy of VRET and ACT for the treatment of other substance use disorders should also be investigated in future.

Clinical trial registration

NCT05841823 (ClinicalTrials.gov).

Nucleus accumbens core acetylcholine receptors modulate the balance of flexible and inflexible cue-directed motivation

Sign-tracking is a conditioned response where animals interact with reward-predictive cues due to the cues having motivational value, or incentive salience. The nucleus accumbens core (NAc) has been implicated in mediating the sign-tracking response. Additionally, acetylcholine (ACh) transmission throughout the striatum has been attributed to both incentive motivation and behavioral flexibility. Here, we demonstrate a role for NAc ACh receptors in the flexibility of sign-tracking. Sign-tracking animals were exposed to an omission contingency, in which vigorous sign-tracking was punished by reward omission. Animals rapidly adjusted their behavior, but they maintained sign-tracking in a less vigorous manner that did not cancel reward. Within this context of sign-tracking being persistent yet flexible in structure, blockade of NAc nicotinic receptors (nAChRs) led to a persistence in the initial sign-tracking response during omission followed by a period of change in the makeup of sign-tracking, whereas blockade of muscarinic receptors (mAChRs) oppositely enhanced the omission-related development of the new sign-tracking behaviors. Later, once omission learning had occurred, nAChR blockade uniquely led to reduced sign-tracking and elevated reward-directed behaviors instead. These results indicate that NAc ACh receptors have opposing roles in maintaining learned patterns of sign-tracking, with nAChRs having a special involvement in regulating the structure of the sign-tracking response.

Changes in dorsomedial striatum activity mediate expression of goal-directed vs. habit-like cue-induced cocaine seeking

A preclinical model of cue exposure therapy, cue extinction, reduces cue-induced cocaine seeking when drug seeking is goal-directed but not habitual. Goal-directed and habitual behaviors differentially rely on the dorsomedial striatum (DMS) and dorsolateral striatum (DLS), but the effects of cue extinction on dorsal striatal responses to cue-induced drug seeking are unknown. We used fiber photometry to examine how dorsal striatal intracellular calcium and extracellular dopamine activity differs between goal-directed and habitual cue-induced cocaine seeking and how it is impacted by cue extinction. Rats trained to self-administer cocaine paired with an audiovisual cue on schedules of reinforcement that promote goal-directed or habitual cocaine seeking had different patterns of dorsal striatal calcium and dopamine responses to cue-reinforced lever presses. Cue extinction reduced calcium and dopamine responses during subsequent drug seeking in the DMS, but not in the DLS. Therefore, cue extinction may reduce goal-directed behavior through its effects on the DMS, whereas habitual behavior and the DLS are unaffected.

CO2 reactivity is associated with individual differences in appetitive extinction memory

Pavlovian conditioning can underly the maladaptive behaviors seen in psychiatric disorders such as anxiety and addiction. In both the lab and the clinic, these responses can be attenuated through extinction learning, but often return with the passage of time, stress, or a change in context. Extinction to fear and reward cues are both subject to these return of behavior phenomena and have overlap in neurocircuitry, yet it is unknown whether they share any common predictors. The orexin system has been implicated in both fear and appetitive extinction and can be activated through a CO2 challenge. We previously found that behavioral CO2 reactivity predicts fear extinction and orexin activation. Here, we sought to extend our previous findings to determine whether CO2 reactivity might also predict extinction memory for appetitive light-food conditioning. We find that the same subcomponent of behavioral CO2 reactivity that predicted fear extinction also predicts appetitive extinction, but in the opposite direction. We show evidence that this subcomponent remains stable across two CO2 challenges, suggesting it may be a stable trait of both behavioral CO2 reactivity and appetitive extinction phenotype. Our findings further the possibility for CO2 reactivity to be used as a transdiagnostic screening tool to determine whether an individual would be a good candidate for exposure therapy.

Meta-review on the efficacy of psychological therapies for the treatment of substance use disorders

This meta-review aimed to summarize the current state of knowledge provided by meta-analyzes on the efficacy of psychotherapies for substance use disorders. A systematic search was performed in PubMed, PsycINFO, Web of Science and Google Scholar. Meta-analyzes were included if they quantitatively examined the efficacy of a psychotherapy on substance use. Among the 6866 potential articles that were screened for eligibility, 23 meta-analyzes were eligible (78 effect sizes). Each meta-analysis included 2-156 studies, with samples ranging between approximately 130 to over 33,000 individuals. The quality of evidence was evaluated as being globally of low to moderate quality. Substances were categorized as: alcohol (k = 12), cannabis (k = 7), stimulants (k = 4), opioids (k = 3) and benzodiazepines (k = 1). Interventions comprised brief intervention, cognitive-behavioral therapy, contingency management, voucher-based reinforcement therapy, motivational interview, motivational enhancement therapy, significant other people involved in the treatment, and cue-expose therapy. Concerning solely significant results, small benefits were observed for significant other people involved in treatment, motivational interviewing, and the combination of cognitive-behavioral therapy with motivational interviewing for alcohol use disorder. Likewise, small-to-moderate effects were found for motivational approaches, and cognitive-behavioral therapy as well as the combination of cognitive-behavioral therapy and motivational enhancement therapy in the case of cannabis use disorder. Small effects were observed for contingency management as well as cognitive behavioral-therapy for amphetamine-type use disorder. Small effects were similarly found for contingency management for cocaine use disorder. Concerning opioid use disorder, moderate effects were observed for contingency management and voucher-based reinforcement intervention. For benzodiazepine use disorder, small effects were noted for cognitive-behavioral therapy with taper. Results often displayed small to moderate heterogeneity when reported and were generally compared to inactive controls, such as treatment-as-usual. In all, the psychosocial treatments for substance use disorders included in this meta-review have shown to be at best moderately effective over inactive controls in the short term. Nevertheless, further trials are needed as well as meta-analyzes on interventions not included in this meta-review.

Avatar Intervention for Cannabis Use Disorder in Individuals with Severe Mental Disorders: A Pilot Study

Cannabis use disorder (CUD) is a complex issue, even more so when it is comorbid with a severe mental disorder (SMD). Available interventions are at best slightly effective, and their effects are not maintained over time. Therefore, the integration of virtual reality (VR) may increase efficacy; however, it has not yet been investigated in the treatment of CUD. A novel approach, avatar intervention for CUD, uses existing therapeutic techniques from other recommended therapies (e.g., cognitive behavioral methods, motivational interviewing) and allows participants to practice them in real-time. During immersive sessions, participants are invited to interact with an avatar representing a significant person related to their drug use. This pilot clinical trial aimed to evaluate the short-term efficacity of avatar intervention for CUD on 19 participants with a dual diagnosis of SMD and CUD. Results showed a significant moderate reduction in the quantity of cannabis use (Cohen's d = 0.611, p = 0.004), which was confirmed via urinary quantification of cannabis use. Overall, this unique intervention shows promising results. Longer-term results, as well as comparison with classical interventions in a larger sample, are warranted through a future single-blind randomized controlled trial.

The traps of adaptation: Addiction as maladaptive referent-dependent evaluation

Referent-dependent evaluation theories propose that the ongoing context influences how the brain attributes value to stimuli. What are the implications of these theories for understanding addiction? The paper asks this question by casting this disorder as a form of maladaptive referent-dependent evaluation. Specifically, addiction is proposed to arise from the establishment of an excessive reference point following repeated drug consumption. Several key aspects of the disorder emerge from this perspective, including withdrawal, tolerance, enhanced craving, negative mood, and diminished stimulus discriminability. As highlighted in the paper, this formulation has important analogies with classical accounts of addiction, such as set point theories and associative learning theories. Moreover, this picture fits with the pattern of striatal dopaminergic activity observed in addiction, a key neural signature of the disorder. Overall, the referent-dependent evaluation approach emerges as a useful add-on to the theoretical toolkit adopted to interpret addiction. This also supports the idea that referent-dependent evaluation might offer a general framework to understand various disorders characterised by disrupted motivation.

The efficacy of cue exposure therapy on alcohol use disorders: A quantitative meta-analysis and systematic review

BACKGROUND

Cue exposure therapy (CET) techniques involves repeated and controlled exposures to alcohol stimuli which rest upon the well-established principles of Pavlovian extinction (Byrne et al., 2019). However, the efficacy of CET while treating alcohol use disorders (AUDs) is still a matter of debate. Therefore, we aimed to investigate the efficacy of CET on AUDs by using previous meta-analysis study on the same topic from Mellentin et al. (2017) as a base.

METHODS

A computer-assisted search of relevant articles identified 879 studies in Medline, PsycInfo and Embase, of which 11 studies (published between 1992 and 2019) were selected. Three outcome measures were extracted: alcohol consumption defined as drinks per day (drinking intensity) and alcohol reduction defined as drinking days and relapse (drinking frequency). This study is registered with PROSPERO (Registration no: #CRD42021259077).

RESULTS

The present meta-analytical review found small to medium effect on drinks per day (g = -0.35; 95 %CI -0.72 to 0.03), drinking days (g = -0.30; 95 %CI -0.54 to -0.06) and relapse (OR = -0.58; 95 %CI 0.29 to 1.15) while investigating the efficacy of CET on AUDs. GRADE assessment was used to evaluate the overall quality, and it was assessed as low. Regarding Risk of Bias, the studies in this systematic review were evaluated with "some concerns".

CONCLUSION

The present meta-analysis demonstrated that CET has small to medium effect on drinks per day, drinking days and relapse. Future research should strive to conduct larger scale multi-site CET trials with additional methodological innovations and increase retention.

Virtual reality-assisted cognitive behavioural therapy for outpatients with alcohol use disorder (CRAVR): a protocol for a randomised controlled trial

INTRODUCTION

Alcohol use disorder (AUD) is a brain disorder linked to over 200 health conditions. Cognitive behavioural therapy (CBT) is considered the best practice in the treatment of AUD, but more than 60% of patients relapse within the first year after treatment. Psychotherapy combined with virtual reality (VR) has received increasing interest in the treatment of AUD. However, existing studies have primarily investigated the use of VR for cue reactivity. We therefore aimed to investigate the effect of VR-assisted CBT (VR-CBT).

METHODS AND ANALYSIS

This study is an assessor-blinded, randomised clinical trial being conducted at three outpatient clinics in Denmark. We will randomise 102 patients to 14 individual sessions of either manualised VR-CBT or CBT. The VR-CBT group will receive exposure to immersive high-risk VR situations from a pub, bar/party, restaurant, supermarket and at-home (30 videos) to activate high-risk-related beliefs and cravings for subsequent modification using CBT techniques. The treatment period is 6 months, and follow-up visits will be performed 3, 6, 9 and 12 months after inclusion. The primary outcome measure is the change in total alcohol consumption from baseline to 6 months after inclusion, measured with the Timeline Followback Method. Key secondary outcome measures include changes in the number of heavy drinking days, alcohol cravings, cognition, and symptoms of depression and anxiety.

ETHICS AND DISSEMINATION

Approval has been obtained by the research ethics committee in the Capital Region of Denmark (H-20082136) and the Danish Data Protection Agency (P-2021-217). All patients will receive both oral and written information about the trial and written informed consent will be obtained from each patient before inclusion. The study results will be disseminated in peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

ClinicalTrial.gov, NCT05042180.

Which interventions for alcohol use should be included in a universal healthcare benefit package? An umbrella review of targeted interventions to address harmful drinking and dependence

BACKGROUND

This study aimed to identify targeted interventions for the prevention and treatment of harmful alcohol use. Umbrella review methodology was used to summarise the effectiveness across a broad range of interventions, in order to identify which interventions should be considered for inclusion within universal health coverage schemes in low- and middle-income countries.

METHODS AND FINDINGS

We included systematic reviews with meta-analysis of randomised controlled trials (RCTs) on targeted interventions addressing alcohol use in harmful drinkers or individuals with alcohol use disorder. We only included outcomes related to alcohol consumption, heavy drinking, binge drinking, abstinence, or alcohol-attributable accident, injury, morbidity or mortality. PubMed, Embase, PsycINFO, Cochrane Database of Systematic Reviews, and the International HTA Database were searched from inception to 3 September 2021. Risk of bias of reviews was assessed using the AMSTAR2 tool. After reviewing the abstracts of 9,167 articles, results were summarised narratively and certainty in the body of evidence for each intervention was assessed using GRADE. In total, 86 studies met the inclusion criteria, of which the majority reported outcomes for brief intervention (30 studies) or pharmacological interventions (29 studies). Overall, methodological quality of included studies was low.

CONCLUSIONS

For harmful drinking, brief interventions, cognitive behavioural therapy, and motivational interviewing showed a small effect, whereas mentoring in adolescents and children may have a significant long-term effect. For alcohol use disorder, social network approaches and acamprosate showed evidence of a significant and durable effect. More evidence is required on the effectiveness of gamma-hydroxybutyric acid (GHB), nalmefene, and quetiapine, as well as optimal combinations of pharmacological and psychosocial interventions. As an umbrella review, we were unable to identify the extent to which variation between studies stemmed from differences in intervention delivery or variation between country contexts. Further research is required on applicability of findings across settings and best practice for implementation. Funded by the Thai Health Promotion Foundation, grant number 61-00-1812.

Modeling cue-exposure therapy for alcohol use disorder in rhesus monkeys: Effects of putative cognitive enhancers

BACKGROUND

Cue-exposure therapy (CET) is an effective approach for anxiety-related disorders, but its effectiveness for substance use disorders is less clear. One potential means of improving CET outcomes is to include a cognitive-enhancing pharmacotherapy. This study evaluated d-cycloserine (DCS) and RY-023, putative cognitive enhancers targeting glutamate and GABA systems, respectively, in a monkey model of CET for alcohol use disorder.

METHODS

Male rhesus monkeys (n = 4) underwent multiple cycles of the CET procedure. During baseline (Phase 1), monkeys self-administered an ethanol solution under a fixed-ratio schedule and limited access conditions such that every 5th response in a 3-h session resulted in 30-s access to a drinking spout and a change in ethanol-paired cue lights from white to red. Behavior then was extinguished (Phase 2) by omitting the ethanol solution yet retaining the ethanol-paired stimulus lights. Monkeys also received injections of vehicle, DCS (3 mg/kg), a partial agonist at the glycine modulatory site on glutamatergic NMDA receptors, or the α5GABAA receptor-selective inverse agonist RY-023 (0.03 or 0.3 mg/kg). Once responding declined, monkeys underwent a cue reactivity test (Phase 3), and then returned to self-administration the following day to assess reacquisition (Phase 4).

RESULTS

Through multiple cycles, self-administration remained stable. Compared to vehicle, DCS facilitated extinction of ethanol seeking (Phase 2) and delayed reacquisition of ethanol self-administration (Phase 4). In contrast, RY-023 facilitated extinction (Phase 2) and reduced cue reactivity (Phase 3).

CONCLUSIONS

Adjunctive pharmacotherapy can improve CET outcomes, but the choice of pharmacotherapy should be dependent on the outcome of interest.

Hippocampal and amygdalar increased BDNF expression in the extinction of opioid-induced place preference

The opioid crisis was exacerbated during the COVID-19 pandemic in the United States with alarming statistics about overdose-related deaths. Current treatment options, such as medication assisted treatments, have been unable to prevent relapse in many patients, whereas cue-based exposure therapy have had mixed results in human trials. To improve patient outcomes, it is imperative to develop animal models of addiction to understand molecular mechanisms and identify potential therapeutic targets. We previously found increased brain derived neurotrophic factor (bdnf) transcript in the ventral striatum/nucleus accumbens (VS/NAc) of rats that extinguished morphine-induced place preference. Here, we expand our study to determine whether BDNF protein expression was modulated in mesolimbic brain regions of the reward system in animals exposed to extinction training. Drug conditioning and extinction sessions were followed by Western blots for BDNF in the hippocampus (HPC), amygdala (AMY) and VS/NAc. Rears, as a measure of withdrawal-induced anxiety were also measured to determine their impact on extinction. Results showed that animals who received extinction training and successfully extinguished morphine CPP significantly increased BDNF in the HPC when compared to animals deprived of extinction training (sham-extinction). This increase was not significant in animals who failed to extinguish (extinction-resistant). In AMY, all extinction-trained animals showed increased BDNF, regardless of behavior phenotype. No BDNF modulation was observed in the VS/NAc. Finally, extinction-trained animals showed no difference in rears regardless of extinction outcome, suggesting that anxiety elicited by drug withdrawal did not significantly impact extinction of morphine CPP. Our results suggest that BDNF expression in brain regions of the mesolimbic reward system could play a key role in extinction of opioid-induced maladaptive behaviors and represents a potential therapeutic target for future combined pharmacological and extinction-based therapies.

Exposure Therapy for Gambling Disorder: Systematic Review and Meta-analysis

Purpose of Review

Cognitive behaviour therapy is the gold standard for the treatment of gambling disorder. Obstacles remain regarding its efficacy, namely relapses and difficulty in implementing cognitive restructuring for some clients. Given these observations, behavioural interventions for gambling disorder, such as exposure therapy, which aims to decrease gambling craving, may be effective as a complementary or alternative intervention to cognitive behaviour therapy. This systematic review and meta-analysis aims to explore how exposure therapy for gambling disorder has been studied and to evaluate its efficacy. To answer these questions, 3406 studies, retrieved using PsycNet, Medline and Google Scholar, were screened.

Recent Findings

After two screenings, 13 papers were selected for the systematic review and five were statistically combined for the meta-analysis. Quantitative results support exposure therapy’s efficacy to decrease gambling craving at post-intervention (g =  − 0.955) and at last follow-up (6 or 12 months; − 1.010). Results also show a large decrease in gambling severity as documented by screening instruments (− 1.087) as well as time spent gambling (− 2.136) at post-intervention. Furthermore, a large decrease in gambling measured via screening instruments (− 1.162) and erroneous beliefs (− 1.308) was found at last follow-up.

Summary

This is the first meta-analysis on behavioural exposure therapy for gambling disorder. Results support that exposure therapy reduces gambling cravings and severity, as well as time spent gambling and erroneous beliefs. These results are discussed in comparison to other therapeutic approaches and are interpreted according to the high risk of bias in included studies.

Pilot testing of an adaptive, individualized inhibitory control training for binge drinking: first evidence on feasibility, acceptance, and efficacy

Background

Deficits in inhibitory control seem to promote habit behavior and therefore play an important role in the development and maintenance of addictive diseases. Although several training approaches have been suggested, there is a considerable lack of knowledge about the best way to improve inhibitory control. Based on a literature review regarding shortcomings of existing trainings, an individualized, adaptive inhibitory control training was developed. We aimed to assess feasibility and acceptance of this training and to provide preliminary results on its efficacy regarding inhibitory control and binge drinking.

Methods

Sixty-one individuals (30 female) with binge drinking behavior were randomly allocated to either an experimental group receiving three sessions of the inhibitory control training or a waitlist control group receiving no training. Before and after the training, the participants performed a Go/NoGo task to assess inhibitory control (commission errors and false reaction time), completed a questionnaire on drinking-related self-control, and reported drinking behavior.

Results

Although the training was feasible and accepted by participants, it did not affect self-control over drinking, inhibitory control or drinking behavior. The relationship between session number and false reaction time was linear for alcohol stimuli, but squared for neutral stimuli.

Conclusion

Although our findings have to be interpreted in the light of some shortcomings, they demonstrate that further research is needed to enhance our understanding of how to improve inhibitory control and which factors might moderate this process.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00426-022-01725-4.

Friend recollections, and a collection of collaborations with Nadia

In this selective review article, we showcase our collaborations with our colleague, Dr. Nadia Chaudhri. Dr. Chaudhri was an esteemed colleague and researcher who contributed greatly to our understanding of Pavlovian alcohol conditioning. From 2014 to 2019, we collaborated with Nadia. Here, we reflect on our friendship, the work we did together, and the continued impact on the field.

A Case for Translation From the Clinic to the Laboratory

Laboratory procedures have been used for decades as analogues for clinical processes with the goal of improving our understanding of psychological treatments for emotional disorders and identifying strategies to make treatments more effective. This research has often focused on translation from the laboratory to the clinic. Although this approach has notable successes, it has not been seamless. There are many examples of strategies that work in the laboratory that fail to lead to improved outcomes when applied clinically. One possible reason for this gap between experimental and clinical research is a failure to focus on translation from the clinic to the laboratory. Here, we discuss potential benefits of translation from the clinic to the laboratory and provide examples of how this might be implemented. We first consider two well-established laboratory analogues (extinction and cognitive reappraisal), identify critical aspects of the related clinical procedures (exposure and cognitive restructuring) that are missing from these analogues, and propose variations to better capture the clinical process. Second, we discuss two clinical procedures that have more recently been brought into the laboratory (eye-movement desensitization and reprocessing and imagery rescripting). We conclude by highlighting potential implications of this proposed shift in focus for translational research.

Relapse prevention for alcohol use disorders: combined acamprosate and cue exposure therapy as aftercare

AIMS

Many patients with alcohol use disorders are challenged by cravings leading to repeated relapses. Both cue exposure therapy (CET) and acamprosate target alcohol cravings and are often combined (CET + acamprosate). The main aim of this study was to investigate whether aftercare treatment consisting of CET combined with acamprosate is equivalent to (A) CET as monotherapy, (B) aftercare as usual (AAU) as monotherapy or (C) AAU combined with acamprosate.

METHODS

Patients were randomized to receive either CET with urge-specific coping skills (USCS) as aftercare or AAU. Acamprosate prescription data were extracted from patient case records. Alcohol consumption, cravings, and USCS were assessed at pre-aftercare, post-aftercare, and 6-month follow-up.

RESULTS

Overall, patients increased their alcohol consumption during and following aftercare treatment, thereby relapsing despite any treatment. However, CET + acamprosate achieved greater abstinence compared to AAU + acamprosate at follow-up (p=.047). CET + acamprosate also reduced number of drinking days (p=.020) and number of days with excessive drinking (p=.020) at post-aftercare, when compared to AAU monotherapy. CET monotherapy increased sensible drinking at post-aftercare compared to AAU monotherapy (p=.045) and AAU + acamprosate (p=.047). Only CET monotherapy showed improvement in cravings, when compared to AAU at follow-up (mean urge level: p=.032; peak urge level: p=.014).

CONCLUSION

The study showed that CET both as monotherapy and combined with acamprosate was superior to AAU monotherapy and AAU + acamprosate in reducing alcohol consumption. Only CET + acamprosate was capable of reducing alcohol consumption in the longer term, indicating that anti-craving medication may not impede CET from exerting an effect on alcohol consumption. Trial registration: ClinicalTrials.gov ID: NCT02298751 (24/11-2014).

Repetitive Transcranial Magnetic Stimulation in Alcohol Dependence: A Randomized, Double-Blind, Sham-Controlled Proof-of-Concept Trial Targeting the Medial Prefrontal and Anterior Cingulate Cortices

BACKGROUND

Alcohol addiction is associated with a high disease burden, and treatment options are limited. In a proof-of-concept study, we used deep repetitive transcranial magnetic stimulation (dTMS) to target circuitry associated with the pathophysiology of alcohol addiction. We evaluated clinical outcomes and explored associated neural signatures using functional magnetic resonance imaging.

METHODS

This was a double-blind, randomized, sham-controlled trial. A total of 51 recently abstinent treatment-seeking patients with alcohol use disorder (moderate to severe) were randomized to sham or active dTMS, using an H7 coil targeting midline frontocortical areas, including the medial prefrontal and anterior cingulate cortices. Treatment included 15 sessions over 3 weeks, followed by five sessions over 3 months of follow-up. Each session delivered 100 trains of 30 pulses at 10 Hz. The primary predefined outcome was reduction in percentage of heavy drinking days, obtained using timeline follow-back interviews. Secondary analyses included self-reports of craving, ethyl glucuronide in urine, and brain imaging measures.

RESULTS

Both craving after treatment and percentage of heavy drinking days during follow-up were significantly lower in the active versus sham control group (percentage of heavy drinking days = 2.9 ± 0.8% vs. 10.6 ± 1.9%, p = .037). Active dTMS was associated with decreased resting-state functional connectivity of the dorsal anterior cingulate cortex with the caudate nucleus and decreased connectivity of the medial prefrontal cortex to the subgenual anterior cingulate cortex.

CONCLUSIONS

We provide initial proof-of-concept for dTMS targeting midline frontocortical structures as a treatment for alcohol addiction. These data strongly support a rationale for a full-scale confirmatory multicenter trial. Therapeutic benefits of dTMS appear to be associated with persistent changes in brain network activity.

Targeting Unmet Clinical Needs in the Treatment of Alcohol Use Disorder

Alcohol Use Disorder (AUD) is a chronic psychiatric disorder marked by impaired control over drinking behavior that poses a significant challenge to the individual, their community, the healthcare system and economy. While the negative consequences of chronic excessive alcohol consumption are well-documented, effective treatment for AUD and alcohol-associated diseases remains challenging. Cognitive and behavioral treatment, with or without pharmaceutical interventions, remain the most commonly used methods; however, their efficacy is limited. The development of new treatment protocols for AUD is challenged by difficulty in accurately measuring patterns of alcohol consumption in AUD patients, a lack of a clear understanding of the neuropsychological basis of the disorder, the high likelihood of AUD patients relapsing after receiving treatment, and the numerous end-organ comorbidities associated with excessive alcohol use. Identification and prediction of patients who may respond well to a certain treatment mechanism as well as clinical measurement of a patient's alcohol exposure are bottlenecks in AUD research which should be further addressed. In addition, greater focus must be placed on the development of novel strategies of drug design aimed at targeting the integrated neural pathways implicated in AUD pathogenesis, so that next-generation AUD treatment protocols can address the broad and systemic effects of AUD and its comorbid conditions.

Effectiveness of Cue-Exposure Therapy on Alcohol Craving in Virtual Environment: Based on habit loop

Background

In the treatment and abstinence of alcoholism, especially in abstinence after treatment, "Craving" has an essential role. Thus, our aim was to examine the effect of cue-exposure therapy on alcohol craving in virtual environment based on the habit loop.

Methods

The present investigation was a case-control experimental study with a pretest-posttest-5 weeks follow-up design. Research population were alcohol-addicted people hospitalized in a psychiatric hospital. We had 62 subjects who had abstained from alcohol consumption. The sampling method was convenience sampling and the sample allocation was randomized and matched. The intervention was VR-CET that was implemented in eight sessions. Penn Alcohol Craving Scale, Alcohol Urge Questionnaire, and Obsessive-Compulsive Drinking Scale were used to collect the data. In order to analyze the data, analysis of covariance (ANCOVA) in SPSS V.23 was performed.

Findings

Our results showed that after implementation of VR-CET program the rate of PACS reduced significantly in posttest stage (p = 0.01) and follow up stage (p= 0.05). Also, the rate of AUQ and OCDS after exposure to VR-CET program declined significantly. The significant level of AUQ and OCDS in posttest and follow up stages were set at p- value < 0.01 and p-value <0.05 respectively.

Conclusion

VR-CET program can reduce alcohol craving by paying attention to various cues and contexts. In fact, it would be more beneficial if the treatment environment resembles a conditioned context and contains as many related cues as possible.

How laboratory studies of cigarette craving can inform the experimental alcohol craving literature

Interest in alcohol and other drug craving has flourished over the past two decades, and evidence has accumulated showing that craving can be meaningfully linked to both drug use and relapse. Considerable human experimental alcohol craving research since 2000 has focused on craving as a clinical phenomenon. Self-reported craving to drink typically has served as a catch-all for the craving construct in these studies, whereas few studies have considered craving as a process (or hypothetical construct) that interacts with other phenomena to affect use. In contrast to alcohol, we believe that recently there has been more mechanistic work targeting cigarette craving-related processes. Here, we briefly present a narrative review of studies of acute alcohol craving in humans that have been conducted during the past two decades. We then specify important ways in which alcohol and tobacco differ (e.g., the role of withdrawal), and we note the unique challenges in inducing robust alcohol craving states in the laboratory. Finally, we offer recommendations for how the alcohol field might advance its conceptual understanding of craving by adopting ideas and methods drawn from the smoking research literature. Specifically, we suggest that researchers extend their studies to not only examine the link between alcohol craving and relapse but also to focus on why and, in some instances, how alcohol cravings matter clinically, and the circumstances under which craving especially matters. We propose research to investigate the shifts in alcohol-related cognitive and affective processing that occur during alcohol craving states. Furthermore, we highlight the value of research examining the level of insight that individuals with varying levels of alcohol involvement possess about their own craving-related processing shifts. We believe that laboratory studies can provide rich opportunities to examine conceptual questions about alcohol craving that are central to addiction.

Virtual reality intervention effects on future self-continuity and delayed reward preference in substance use disorder recovery: pilot study results

Sustained remission from substance use disorder (SUD) is challenged by high relapse rates, which provides opportunities for novel clinical interventions. Immersive virtual reality (VR) permits delivering synthetic experiences that feel real and actualizes otherwise impossible scenarios for therapeutic benefit. We report on the feasibility of an immersive VR intervention designed to increase valuation of the future by enhancing future self-continuity and leveraging future self-discrepancy with personalized future selves as SUD recovery support. Twenty-one adults in early SUD recovery (< 1 year) interacted with versions of themselves age-progressed fifteen years from two different behavioral trajectories: an SUD Future Self and a Recovery Future Self. The future selves' interactive monologs include personalized details and voice for a lifelike interaction within a time travel vignette. Before and following the intervention, participants rated future self-continuity and performed delay discounting. Following the intervention, daily images of the Recovery Future Self were sent to participants' smartphones for thirty days. The VR intervention generated no adverse events, was well tolerated (presence, liking, and comfort), and significantly increased future self-continuity and delayed reward preference (doubling delay tolerance). The intervention also reduced craving, ps < 0.05. Thirty days later, n = 18 remained abstinent; importantly, increased future self-similarity persisted. Abstainers' future self-similarity increased following VR. All individual participants showing increased future self-similarity post-VR remained abstinent, and all participants who relapsed showed either reduced or zero effect on future self-similarity. Post-intervention semi-structured interviews revealed emotional engagement with the experience. VR simulation of imagined realities reifies novel clinical interventions that are practicable and personalized. The current study demonstrates an implementation readily applied in the clinic and shows promise for facilitating SUD recovery. Creative collaboration between researchers, clinicians, and VR developers has great potential to revolutionize mental health interventions and expand the range of tools for clinicians targeting SUD and other disorders.

Supplementary Information

The online version contains supplementary material available at 10.1007/s44192-022-00022-1.

Exposure to Olfactory Alcohol Cues During Non-rapid Eye Movement Sleep Did Not Decrease Craving in Patients With Alcohol Dependence

BACKGROUND AND OBJECTIVES

Cue exposure therapy (CET) has been used to reduce alcohol use, but the effect of CET during sleep on alcohol dependence (AD) is unclear. The present study examined the effect of repeated exposure to an olfactory stimulus during non-rapid eye movement (NREM) sleep on cue reactivity and craving in patients with AD.

METHODS

Thirty-five patients with AD were enrolled according to the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV). All the subjects were randomly assigned to the experimental or control group. The experimental group was exposed to alcohol odor for 10 min during NREM sleep. The other group (controls) was exposed to water [control stimulus (CtrS)] for 10 min during NREM sleep. Demographic, alcohol-related, and clinical characteristics were collected at baseline. A cue-reactivity test was conducted before and after exposure to evaluate the effect of memory manipulation on acute response to an alcohol stimulus.

RESULTS

There were no significant time × group interactions according to the visual analog scale (VAS) score of craving intensity, skin conductance response (SCR), systolic blood pressure (SBP), and diastolic blood pressure (DBP; all p > 0.05). Two-way ANOVA showed significant main effects of time on SCR [F _(1,33) = 4.453, p = 0.043], SBP [F _(1,33) = 14.532, p = 0.001], DBP [F _(1,33) = 8.327, p = 0.007], Craving-VAS [F _(1,33) = 1.997, p = 0.167] in two groups.

CONCLUSION

Exposure to olfactory alcohol cues during NREM sleep had no significant effect on alcohol craving in subjects with AD during hospitalization.

The Good, the Bad, and the Ugly-Chances, Challenges, and Clinical Implications of Avoidance Research in Psychosomatic Medicine

Avoidance behaviors are shaped by associative learning processes in response to fear of impending threats, particularly physical harm. As part of a defensive repertoire, avoidance is highly adaptive in case of acute danger, serving a potent protective function. However, persistent or excessive fear and maladaptive avoidance are considered key factors in the etiology and pathophysiology of anxiety- and stress-related psychosomatic disorders. In these overlapping conditions, avoidance can increase the risk of mental comorbidities and interfere with the efficacy of cognitive behavioral treatment approaches built on fear extinction. Despite resurging interest in avoidance research also in the context of psychosomatic medicine, especially in conditions associated with pain, disturbed interoception, and disorders of the gut-brain axis, current study designs and their translation into the clinical context face significant challenges limiting both, the investigation of mechanisms involved in avoidance and the development of novel targeted treatment options. We herein selectively review the conceptual framework of learning and memory processes, emphasizing how classical and operant conditioning, fear extinction, and return of fear shape avoidance behaviors. We further discuss pathological avoidance and safety behaviors as hallmark features in psychosomatic diseases, with a focus on anxiety- and stress-related disorders. Aiming to emphasize chances of improved translational knowledge across clinical conditions, we further point out limitations in current experimental avoidance research. Based on these considerations, we propose means to improve existing avoidance paradigms to broaden our understanding of underlying mechanisms, moderators and mediators of avoidance, and to inspire tailored treatments for patients suffering from psychosomatic disorders.

Psychological Interventions on Abstinence in Patients with Alcohol Use Disorder: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

PURPOSE

Accumulating research suggests that psychotherapy helps improve abstinence but the difference in the efficacy of multiple psychotherapies in alcohol use disorder (AUD) remains to be explored.

PATIENTS AND METHODS

A systematic search of databases (Pubmed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and EBSCO) for studies (published from inception to April 10th.) of adults diagnosed with AUD accepting psychotherapies was conducted. Studies covering 9 countries and regions. The qualitative analysis pooled 2646 individuals from 34 randomized controlled trials (RCTs) and the networks included 1928 participants (23 RCTs). The outcomes included percentage of days abstinent (PDA), change in drinks per drinking day (change in DDD), and change in craving compared among individuals accepting various psychotherapies. The protocol followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), and was registered on the International Prospective Register of Systematic Reviews (PROSPERO).

RESULTS

For the network of PDA, motivational enhancement treatment (MET) (35.44, 11.78 to 59.09, high-certainty) and couple therapy (CT) (28.89, 13.42 to 44.36, moderate-certainty) were significantly different from treatment as usual (TAU) with the surface under the cumulative ranking curve (SUCRA) mean rank 1.9 and 1.9 respectively. TAU+supportive psychotherapy (SP) was better than TAU for the change in DDD in the high-quality direct comparison.

CONCLUSION

The motivational enhancement and the couple therapy show potential amelioration for alcohol abstinence. Additionally, the preferred interventions are different for improving PDA and change in DDD. The evidence network remains to be strengthened.

Deconstructing and reconstructing behaviour relevant to mental health disorders: The benefits of a psychological approach, with a focus on addiction

RUTHERFORD, L.G. and Milton, A.L. Deconstructing and reconstructing behaviour relevant to mental health disorders: what can psychology offer? NEUROSCI BIOBEHAV REV XX(X)XXX-XXX, 2021. - Current treatments for mental health disorders are successful only for some patients, and there is an unmet clinical need for new treatment development. One challenge for treatment development has been how best to model complex human conditions in animals, where mechanism can be more readily studied with a range of neuroscientific techniques. We suggest that an approach to modelling based on associative animal learning theory provides a good framework for deconstructing complex mental health disorders such that they can be studied in animals. These individual simple models can subsequently be used in combination to 'reconstruct' a more complex model of the mental health disorder of interest. Using examples primarily from the field of drug addiction, we explore the 'psychological approach' and suggest that in addition to facilitating translation and backtranslation of tasks between animal models and patients, it is also highly concordant with the concept of triangulation.

Elements of Neuroanthropology

Neuroanthropology is the integration of neuroscience into anthropology and aims to understand “brains in the wild.” This interdisciplinary field examines patterns of human variation in field settings and provides empirical research that complements work done in clinical and laboratory settings. Neuroanthropology often uses ethnography in combination with theories and methods from cognitive science as a way to capture how culture, mind, and brain interact. This article describes nine elements that outline how to do neuroanthropology research: (1) integrating biology and culture through neuroscience and biocultural anthropology; (2) extending focus of anthropology on what people say and do to include what people process; (3) sizing culture appropriately, from broad patterns of culture to culture in small-scale settings; (4) understanding patterns of cultural variation, in particular how culture produces patterns of shared variation; (5) considering individuals in interaction with culture, with levels of analysis that can go from biology to social structures; (6) focusing on interactive elements that bring together biological and cultural processes; (7) conceptual triangulation, which draws on anthropology, psychology, and neuroscience in conjunction with field, clinic, and laboratory; (8) critical complementarity as a way to integrate the strengths of critical scholarship with interdisciplinary work; and (9) using methodological triangulation as a way to advance interdisciplinary research. These elements are illustrated through three case studies: research on US combat veterans and how they use Brazilian Jiu Jitsu as a way to manage the transition to becoming civilians, work on human-raptor interactions to understand how and why these interactions can prove beneficial for human handlers, and adapting cue reactivity research on addiction to a field-based approach to understand how people interact with cues in naturalistic settings.

Virtual Reality Technology Use in Cigarette Craving and Smoking Interventions (I "Virtually" Quit): Systematic Review

BACKGROUND

Over the last 2 decades, virtual reality technologies (VRTs) have been proposed as a way to enhance and improve smoking cessation therapy.

OBJECTIVE

This systematic review aims to evaluate and summarize the current knowledge on the application of VRT in various smoking cessation therapies, as well as to explore potential directions for future research and intervention development.

METHODS

A literature review of smoking interventions using VRT was conducted.

RESULTS

Not all intervention studies included an alternative therapy or a placebo condition against which the effectiveness of the intervention could be benchmarked, or a follow-up measure to ensure that the effects were lasting. Virtual reality (VR) cue exposure therapy was the most extensively studied intervention, but its effect on long-term smoking behavior was inconsistent. Behavioral therapies such as a VR approach-avoidance task or gamified interventions were less common but reported positive results. Notably, only 1 study combined Electronic Nicotine Delivery Devices with VRT.

CONCLUSIONS

The inclusion of a behavioral component, as is done in the VR approach-avoidance task and gamified interventions, may be an interesting avenue for future research on smoking interventions. As Electronic Nicotine Delivery Devices are still the subject of much controversy, their potential to support smoking cessation remains unclear. For future research, behavioral or multicomponent interventions are promising avenues of exploration. Future studies should improve their validity by comparing their intervention group with at least 1 alternative or placebo control group, as well as incorporating follow-up measures.

Simvastatin Blocks Reinstatement of Cocaine-induced Conditioned Place Preference in Male Mice with Brain Lipidome Remodeling

Drug-associated reward memories are conducive to intense craving and often trigger relapse. Simvastatin has been shown to regulate lipids that are involved in memory formation but its influence on other cognitive processes is elusive. Here, we used a mass spectrometry-based lipidomic method to evaluate the impact of simvastatin on the mouse brain in a cocaine-induced reinstatement paradigm. We found that simvastatin blocked the reinstatement of cocaine-induced conditioned place preference (CPP) without affecting CPP acquisition. Specifically, only simvastatin administered during extinction prevented cocaine-primed reinstatement. Global lipidome analysis showed that the nucleus accumbens was the region with the greatest degree of change caused by simvastatin. The metabolism of fatty-acids, phospholipids, and triacylglycerol was profoundly affected. Simvastatin reversed most of the effects on phospholipids induced by cocaine. The correlation matrix showed that cocaine and simvastatin significantly reshaped the lipid metabolic pathways in specific brain regions. Furthermore, simvastatin almost reversed all changes in the fatty acyl profile and unsaturation caused by cocaine. In summary, pre-extinction treatment with simvastatin facilitates cocaine extinction and prevents cocaine relapse with brain lipidome remodeling.

Clinical Relevance of Immersive Virtual Reality in the Assessment and Treatment of Addictive Disorders: A Systematic Review and Future Perspective

(1) Background: Virtual reality (VR) has been investigated in a variety of psychiatric disorders, including addictive disorders (ADs); (2) Objective: This systematic review evaluates the current evidence of immersive VR (using head-mounted displays) in the clinical assessment and treatment of ADs; (3) Method: PubMed and PsycINFO were queried for publications up to November 2020; (4) Results: We screened 4519 titles, 114 abstracts and 85 full-texts, and analyzed 36 articles regarding the clinical assessment (i.e., diagnostic and prognostic value; n = 19) and treatment (i.e., interventions; n = 17) of ADs. Though most VR assessment studies (n = 15/19) showed associations between VR-induced cue-reactivity and clinical parameters, only two studies specified diagnostic value. VR treatment studies based on exposure therapy showed no or negative effects. However, other VR interventions like embodied and aversive learning paradigms demonstrated positive findings. The overall study quality was rather poor; (5) Conclusion: Though VR in ADs provides ecologically valid environments to induce cue-reactivity and provide new treatment paradigms, the added clinical value in assessment and therapy remains to be elucidated before VR can be applied in clinical care. Therefore, future work should investigate VR efficacy in randomized clinical trials using well-defined clinical endpoints.

Nalmefene attenuates neural alcohol cue-reactivity in the ventral striatum and subjective alcohol craving in patients with alcohol use disorder

RATIONALE

Alcohol use disorder is a common and devastating mental illness for which satisfactory treatments are still lacking. Nalmefene, as an opioid receptor modulator, could pharmacologically support the reduction of drinking by reducing the (anticipated) rewarding effects of alcohol and expanding the range of treatment options. It has been hypothesized that nalmefene acts via an indirect modulation of the mesolimbic reward system. So far, only a few imaging findings on the neuronal response to nalmefene are available.

OBJECTIVES

We tested the effect of a single dose of 18 mg nalmefene on neuronal cue-reactivity in the ventral and dorsal striatum and subjective craving.

METHODS

Eighteen non-treatment-seeking participants with alcohol use disorder (67% male, M = 50.3 ± 13.9 years) with a current high-risk drinking level (M = 76.9 ± 52 g of pure alcohol per day) were investigated using a cue-reactivity task during functional magnetic resonance imaging (fMRI) in a double-blind, placebo-controlled, cross-over study/design. In addition, self-reported craving was assessed before and after exposure to alcohol cues.

RESULTS

An a priori defined region of interest (ROI) analysis of fMRI data from 15 participants revealed that nalmefene reduced alcohol cue-reactivity in the ventral, but not the dorsal striatum. Additionally, the subjective craving was significantly reduced after the cue-reactivity task under nalmefene compared to placebo.

CONCLUSION

In the present study, reduced craving and cue-reactivity to alcohol stimuli in the ventral striatum by nalmefene indicates a potential anti-craving effect of this drug via attenuation of neural alcohol cue-reactivity.

Is Virtual Reality Cue Exposure a Promising Adjunctive Treatment for Alcohol Use Disorder?

This narrative review presents recent developments in virtual reality (VR)-based interventions for alcohol use disorders (AUDs). The latest advances in mental healthcare hail an imminent cyber revolution, ushering in novel treatment options, with immersive virtual technology at the very forefront of expected change. With an aim to (a) provide a background on VR use in mental healthcare of AUD patients, (b) summarize existing evidence on conventional approaches to the treatment of AUDs and a trending paradigm shift towards VR applications in their management, and (c) describe key issues and future directions in research on craving assessment and VR cue-induced therapy in AUDs, a search for experimental and meta-analytic evidence was performed in six databases: PubMed and EBSCO (Medline, ERIC, PsychINFO, Academic Search Ultimate, and Health Source: Nursing/Academic Edition). Pooled results were screened for eligibility, and relevant papers were selected for inclusion. The analysis revealed VR’s promising effects in the treatment of AUDs. Its remarkable potential to simulate cues underlying subsequent addictive behaviors makes its application in the assessment and treatment of AUDs an attractive alternative to researchers and clinicians alike. Nevertheless, more evidence is needed before virtual reality cue exposure therapy (VR-CET) can become a clinical standard of care.

Views of Practitioners and Researchers on the Use of Virtual Reality in Treatments for Substance Use Disorders

Virtual Reality Therapy (VRT) has been shown to be effective in treating anxiety disorders and phobias, but has not yet been widely tested for Substance Use Disorders (SUDs) and it is not known whether health care practitioners working with SUDs would use VRT if it were available. We report the results of an interview study exploring practitioners’ and researchers’ views on the utility of VRT for SUD treatment. Practitioners and researchers with at least two years’ experience delivering or researching and designing SUD treatments were recruited (n = 14). Interviews were thematically analyzed, resulting in themes relating to the safety and realism of VRT, and the opportunity for the additional insight it could offer to during SUD treatment. Participants were positive about employing VRT as an additional treatment for SUD. VRT was thought suitable for treating adults and people with mental health issues or trauma, provided that risks were appropriately managed. Subsequent relapse, trauma and over-confidence in the success of treatment were identified as risks. The opportunity VRT offered to include other actors in therapy (via avatar use), and observe reactions, were benefits that could not currently be achieved with other forms of therapy. Overall, VRT was thought to offer the potential for safe, realistic, personalized and insightful exposure to diverse triggering scenarios, and to be acceptable for integration into a wide range of SUD treatments.

Determinants of Cue-Elicited Alcohol Craving and Perceived Realism in Virtual Reality Environments among Patients with Alcohol Use Disorder

The identification of variables that can modulate the efficacy of cue exposure using virtual reality (VR) is crucial. This study aimed to explore determinant variables of cue-elicited alcohol craving and perceived realism (PR) of environments and alcoholic beverages during a VR cue-exposure session among alcohol use disorder (AUD) outpatients. A prospective cohort study was conducted amongst 72 outpatients with AUD from a clinical setting. Alcohol craving experienced during VR exposure and PR of virtual environments and alcoholic drinks were evaluated after a VR session of exposure to alcohol-related contexts and cues. Sociodemographic, psychological and consumption characteristics were examined as possible predicting variables. Multiple linear regression analyses showed that the AUD severity and PR of beverages were predictors of cue-elicited alcohol craving. Educational level, PR of beverages and age were predictors of the PR of VR environments. In relation to the PR of VR beverages, cue-elicited alcohol craving and the PR of environments were predictors. A simple mediational model was also performed to analyze the influence of the PR of beverages on the relationship between the AUD severity and alcohol craving experienced during VR exposure: an indirect or mediational effect was found. PR of alcoholic beverages was (1) a key predictor of the PR of VR environments (and vice versa) and the alcohol craving (and vice versa) experienced during VR cue-exposure sessions using ALCO-VR software among AUD patients and (2) a mediator between AUD severity and cue-elicited alcohol craving.