Methamphetamine craving induced in an online virtual reality environment

Towards virtual reality exposure therapy for cocaine use disorder: A feasibility study of inducing cocaine craving through virtual reality

Background

Craving is a core symptom of cocaine use disorders (CUD). Inducing craving in exposure to substance cues is of relevant interest for numerous clinical applications. Virtual reality exposure (VRE) might be a promising candidate for improving cue-exposure paradigms but remains almost not studied for cocaine. This feasibility study's main aim is to assess whether VRE to cocaine cues is capable to induce cocaine craving compared with VRE to neutral cues.

Methods

We conducted a within-subjects controlled trial in which cocaine users performed 3 consecutive 10 mins-tasks: VRE to neutral and cocaine cues, and a relaxation-based resting procedure. The primary outcome was the change in Cocaine Craving Questionnaire-Brief (CCQ-Brief) scores between VRE to neutral and cocaine cues. Secondary outcomes included between-tasks changes in scores of cocaine craving, pleasant/unpleasant emotions as well as self-efficacy to cope with craving.

Results

We recruited 11 chronic cocaine users including mostly crack smokers (45 %), cocaine snorters (36 %) and injectors (18 %), with 73 % of participants meeting DSM-IV criteria for cocaine dependence and/or abuse. Non-parametrical sign tests indicated significant large increases of CCQ-Brief scores from neutral to cocaine cue-VRE (S(11) = 11, p < 0.01, Cliff's Δ = 0.65, 95 % CI: 0.17-0.88). Exploratory comparative analyses indicated significant changes after our post-cues VRE relaxation procedure, with cocaine craving and emotions restored to baseline.

Conclusions

VRE to cocaine cues was feasible and capable to induce cocaine craving in cocaine users. This second VRE-based cue-reactivity study in cocaine paves the way for unexplored research on VRE clinical applications for CUD.

Use of Virtual Reality and 3D Models in Contemporary Practice of Cardiology

PURPOSE OF REVIEW

To provide an overview of the impact of virtual and augmented reality in contemporary cardiovascular medical practice.

RECENT FINDINGS

The utilization of virtual and augmented reality has emerged as an innovative technique in various cardiovascular subspecialties, including interventional adult, pediatric, and adult congenital as well as structural heart disease and heart failure. In particular, electrophysiology has proven valuable for both diagnostic and therapeutic procedures. The incorporation of 3D reconstruction modeling has significantly enhanced our understanding of patient anatomy and morphology, thereby improving diagnostic accuracy and patient outcomes. The interactive modeling of cardiac structure and function within the virtual realm plays a pivotal role in comprehending complex congenital, structural, and coronary pathology. This, in turn, contributes to safer interventions and surgical procedures. Noteworthy applications include septal defect device closure, transcatheter valvular interventions, and left atrial occlusion device implantation. The implementation of virtual reality has been shown to yield cost savings in healthcare, reduce procedure time, minimize radiation exposure, lower intravenous contrast usage, and decrease the extent of anesthesia required. These benefits collectively result in a more efficient and effective approach to patient care.

Applications of TMS in individuals with methamphetamine use disorder: A review

Methamphetamine abuse results in a host of social and medical issues. Methamphetamine use disorder (MUD) can hinder the brain and impair cognitive functions and mental health. Transcranial magnetic stimulation (TMS) is a non-invasive approach in the treatment of MUD. Recent studies have demonstrated encouraging and positive effects of TMS on the craving, affective symptoms, sleep quality, and cognitive functions in individuals with MUD. The regulation of specific brain activities through TMS has also been found to be a contributing factor to these positive outcomes. It is essential to employ more techniques, participants, and stimulation parameters and targets in the future.

Effects of a virtual reality-based motivational reinforcement + desensitization intervention program on psychological craving and addiction memory in female MA-dependent young adults

OBJECTIVES

The aim of this study was to explore the effects of a virtual reality (VR)-based motivational reinforcement + desensitization intervention program on psychological craving and addiction memory in female methamphetamine (MA)-dependent young adults.

METHODS

We recruited 60 female MA-dependent young adults in a compulsory isolation drug rehabilitation facility in Sichuan Province, and randomly assigned them to intervention (mean age = 23.24 ± 2.06) and control groups (mean age = 23.33 ± 2.09). The intervention group received a VR-based motivational enhancement + desensitization intervention (total of eight sessions over a 4-week period), while the control group received regular detoxification management during the same period. Assessments were conducted before, immediately after, and 1 month after the intervention, with a visual analogue scale (VAS) being used to assess subjective craving, electronic sphygmomanometer employed to measure physiological parameters, and the Addiction Memory Intensity Scale (AMIS) applied to assess addiction memory intensity.

RESULTS

Generalized estimating equation analysis showed significant main effects of group on changes in heart rate difference, systolic blood pressure difference, VAS and AMIS scores (all p < 0.01), and a significant time main effect on changes in diastolic blood pressure difference, VAS and AMIS scores (all p < 0.01), and a significant group × time interaction effect on changes in the difference values of three physiological parameters, VAS and AMIS scores (p < 0.01 or p < 0.05). After the intervention, the differences in three physiological parameters, and the VAS and AMIS scores, were significantly lower in the intervention than in the control group (all p < 0.05), and the difference between the two groups remained significant 1 month after the end of the intervention (both p < 0.01). VAS scores, heart rate difference, and diastolic blood pressure difference in the intervention group were significantly lower than baseline scores, both at the end of the intervention and 1 month thereafter (all p < 0.01); the systolic blood pressure difference in the intervention group was significantly lower at the end of the intervention than at baseline (p < 0.05); AMIS scores in the intervention group were significantly lower than the baseline scores 1 month after the end of the intervention (p < 0.01).

CONCLUSION

Our VR-based motivational reinforcement + desensitization intervention program can effectively reduce psychological craving and physiological reactivity for drugs, and the intensity of addictive memories in female MA-dependent young adults, even after 1 month.

Adenosine receptor stimulation inhibits methamphetamine-associated cue seeking

BACKGROUND

Methamphetamine (METH) is a psychostimulant drug that remains a popular and threatening drug of abuse with high abuse liability. There is no established pharmacotherapy to treat METH dependence, but evidence suggests that stimulation of adenosine receptors reduces the reinforcing properties of METH and could be a potential pharmacological target. This study examines the effects of adenosine receptor subtype stimulation on METH seeking using both a cue-induced reinstatement and cue-craving model of relapse.

METHODS

Male and female rats were trained to self-administer METH during daily 2-h sessions. Cue-induced reinstatement of METH seeking was evaluated after extinction training. A systemic pretreatment of an adenosine A1 receptor (A1R) or A2A receptor (A2AR) agonist was administered prior to an extinction or cue session to evaluate the effects of adenosine receptor subtype stimulation on METH seeking. The effects of a systemic pretreatment of A1R or A2AR agonists were also evaluated in a cue-craving model where the cued-seeking test was conducted after 21 days of forced home-cage abstinence without extinction training.

RESULTS

Cue-induced reinstatement was reduced in both male and female rats that received A1R or A2AR agonist pretreatments. Similarly, an A1R or A2AR agonist pretreatment also inhibited cue craving in both male and female rats.

CONCLUSION

Stimulation of either adenosine A1R or A2AR subtypes inhibits METH-seeking behavior elicited by METH-associated cues. These effects may be attributed to the ability of A1R and A2AR stimulation to disrupt cue-induced dopamine and glutamate signaling throughout the brain.

VR for Studying the Neuroscience of Emotional Responses

Emotions are frequently considered as the driving force of behavior, and psychopathology is often characterized by aberrant emotional responding. Emotional states are reflected on a cognitive-verbal, physiological-humoral, and motor-behavioral level but to date, human research lacks an experimental protocol for a comprehensive and ecologically valid characterization of such emotional states. Virtual reality (VR) might help to overcome this situation by allowing researchers to study mental processes and behavior in highly controlled but reality-like laboratory settings. In this chapter, we first elucidate the role of presence and immersion as requirements for eliciting emotional states in a virtual environment and discuss different VR methods for emotion induction. We then consider the organization of emotional states on a valence continuum (i.e., from negative to positive) and on this basis discuss the use of VR to study threat processing and avoidance as well as reward processing and approach behavior. Although the potential of VR has not been fully realized in laboratory and clinical settings yet, this technological tool can open up new avenues to better understand the neurobiological mechanisms of emotional responding in healthy and pathological conditions.

Electroencephalogram pattern association with drug-related cues in a long-duration virtual reality environment in patients with methamphetamine use disorder

The cognitive processing of drug-related cues and the subsequent dysregulation of behaviour play a central role in the pathophysiology of substance use disorders. Prior studies are limited by small sample sizes and a lack of immersion in stimulus presentation. In the present study, we recruited patients with methamphetamine use disorder (MUD; N = 1099) from four compulsory isolated detoxification centres and healthy control participants (N = 305). With a 12-min-long virtual reality (VR) protocol stimulus, we discovered that patients showed a decrease in electroencephalogram (EEG) power across alpha to gamma bands in anterior scalp regions under methamphetamine-related VR stimuli (e.g. a glass pipe and medical tubing) compared with the control stimuli (e.g. balls and cubes). Analysis of variance (ANOVA) showed that the interaction effects of stimuli type and group were significant in five EEG bands. Using generalised linear models, we classified the stimuli type (i.e. drug-related vs. drug-unrelated cues) in MUD patients with an f1 score of 90% on an out-of-sample testing set. The decreases of EEG between drug-related cues and drug-unrelated cues in delta, theta and alpha frequency bands are more frequently seen in patients than in healthy controls, perhaps reflecting general arousal and attenuated impulsive control. Our results suggest that EEG responses elicited by long-duration methamphetamine-related VR cues showed a specific signature, which may have future clinical implications.

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.

Challenges and future trends in wearable closed-loop neuromodulation to efficiently treat methamphetamine addiction

Achieving abstinence from drugs is a long journey and can be particularly challenging in the case of methamphetamine, which has a higher relapse rate than other drugs. Therefore, real-time monitoring of patients' physiological conditions before and when cravings arise to reduce the chance of relapse might help to improve clinical outcomes. Conventional treatments, such as behavior therapy and peer support, often cannot provide timely intervention, reducing the efficiency of these therapies. To more effectively treat methamphetamine addiction in real-time, we propose an intelligent closed-loop transcranial magnetic stimulation (TMS) neuromodulation system based on multimodal electroencephalogram-functional near-infrared spectroscopy (EEG-fNIRS) measurements. This review summarizes the essential modules required for a wearable system to treat addiction efficiently. First, the advantages of neuroimaging over conventional techniques such as analysis of sweat, saliva, or urine for addiction detection are discussed. The knowledge to implement wearable, compact, and user-friendly closed-loop systems with EEG and fNIRS are reviewed. The features of EEG and fNIRS signals in patients with methamphetamine use disorder are summarized. EEG biomarkers are categorized into frequency and time domain and topography-related parameters, whereas for fNIRS, hemoglobin concentration variation and functional connectivity of cortices are described. Following this, the applications of two commonly used neuromodulation technologies, transcranial direct current stimulation and TMS, in patients with methamphetamine use disorder are introduced. The challenges of implementing intelligent closed-loop TMS modulation based on multimodal EEG-fNIRS are summarized, followed by a discussion of potential research directions and the promising future of this approach, including potential applications to other substance use disorders.

Virtual reality in the diagnostic and therapy for mental disorders: A systematic review

BACKGROUND

Virtual reality (VR) technologies are playing an increasingly important role in the diagnostics and treatment of mental disorders.

OBJECTIVE

To systematically review the current evidence regarding the use of VR in the diagnostics and treatment of mental disorders.

DATA SOURCE

Systematic literature searches via PubMed (last literature update: 9^th of May 2022) were conducted for the following areas of psychopathology: Specific phobias, panic disorder and agoraphobia, social anxiety disorder, generalized anxiety disorder, posttraumatic stress disorder (PTSD), obsessive-compulsive disorder, eating disorders, dementia disorders, attention-deficit/hyperactivity disorder, depression, autism spectrum disorder, schizophrenia spectrum disorders, and addiction disorders.

ELIGIBILITY CRITERIA

To be eligible, studies had to be published in English, to be peer-reviewed, to report original research data, to be VR-related, and to deal with one of the above-mentioned areas of psychopathology.

STUDY EVALUATION

For each study included, various study characteristics (including interventions and conditions, comparators, major outcomes and study designs) were retrieved and a risk of bias score was calculated based on predefined study quality criteria.

RESULTS

Across all areas of psychopathology, k = 9315 studies were inspected, of which k = 721 studies met the eligibility criteria. From these studies, 43.97% were considered assessment-related, 55.48% therapy-related, and 0.55% were mixed. The highest research activity was found for VR exposure therapy in anxiety disorders, PTSD and addiction disorders, where the most convincing evidence was found, as well as for cognitive trainings in dementia and social skill trainings in autism spectrum disorder.

CONCLUSION

While VR exposure therapy will likely find its way successively into regular patient care, there are also many other promising approaches, but most are not yet mature enough for clinical application.

REVIEW REGISTRATION

PROSPERO register CRD42020188436.

FUNDING

The review was funded by budgets from the University of Bonn. No third party funding was involved.

Impaired Brain-Heart Relation in Patients With Methamphetamine Use Disorder During VR Induction of Drug Cue Reactivity

Methamphetamine use disorder (MUD) is an illness associated with severe health consequences. Virtual reality (VR) is used to induce the drug-cue reactivity and significant EEG and ECG abnormalities were found in MUD patients. However, whether a link exists between EEG and ECG abnormalities in patients with MUD during exposure to drug cues remains unknown. This is important from the therapeutic viewpoint because different treatment strategies may be applied when EEG abnormalities and ECG irregularities are complications of MUD. We designed a VR system with drug cues and EEG and ECG were recorded during VR exposure. Sixteen patients with MUD and sixteen healthy subjects were recruited. Statistical tests and Pearson correlation were employed to analyze the EEG and ECG. The results showed that, during VR induction, the patients with MUD but not healthy controls showed significant [Formula: see text] and [Formula: see text] power increases when the stimulus materials were most intense. This finding indicated that the stimuli are indiscriminate to healthy controls but meaningful to patients with MUD. Five heart rate variability (HRV) indexes significantly differed between patients and controls, suggesting abnormalities in the reaction of patient's autonomic nervous system. Importantly, significant relations between EEG and HRV indexes changes were only identified in the controls, but not in MUD patients, signifying a disruption of brain-heart relations in patients. Our findings of stimulus-specific EEG changes and the impaired brain-heart relations in patients with MUD shed light on the understanding of drug-cue reactivity and may be used to design diagnostic and/or therapeutic strategies for MUD.

How drug cravings affect metacognitive monitoring in methamphetamine abusers

BACKGROUND AND OBJECTIVE

Metacognitive monitoring refers to the process in which an individual analyzes their own mental state, then monitors and adjusts cognitive activities to achieve a predetermined goal. Recent research has suggested a strong link between metacognition and drug cravings. Conversely, few studies on the impact of metacognitive monitoring on methamphetamine (MA) cravings exist. Thus, this study investigated whether drug cravings would impair MA abusers' metacognitive monitoring and explored the prediction effects of drug cravings.

METHOD

Seventy MA abusers from the Zhejiang Compulsory Isolation Drug Rehabilitation Center and 65 non-users from the Wenzhou Medical University were recruited for this experimental study. The judgment of learning (JOL) paradigm was used to examine metacognitive monitoring, and cue-induced pictures were used to induce MA abusers' drug cravings. Analysis of covariance (ANCOVA), partial correlation, and regression analysis were performed.

RESULTS

Compared with non-users, MA abusers had significantly poorer metacognitive monitoring and tended to overestimate their performance. Furthermore, there was a significant correlation between the accuracy of JOLs and drug cravings, which indicated that metacognitive monitoring was weakened by drug cravings with higher cravings imposing more severe impacts. In addition, the regression analysis suggested that drug cravings can predict metacognitive monitoring.

Theta-Burst Stimulation Combined With Virtual-Reality Reconsolidation Intervention for Methamphetamine Use Disorder: Study Protocol for a Randomized-Controlled Trial

Background

Craving associated with drug-related memory is one of the key factors that induce the relapse of methamphetamine (MA). Disruption or modulation of the reconsolidation of drug-related memory may serve as an option for clinical treatment of MA addiction. This protocol proposes to use virtual reality (VR) to retrieve drug-associated memory and then use transcranial magnetic stimulation (TMS) at the neural circuit that encodes the reward value of drug cues to provide a non-invasive intervention during reconsolidation. We aim to evaluate the effectiveness of TMS treatment after VR retrieval on the reduction of cue reactivity and craving of MA.

Methods

This is a randomized, double-blind, sham-controlled, parallel group trial, targeting participants with MA use disorder aged from 18 to 45 years old. Forty-five eligible volunteers in Shanxi Drug Rehabilitation Center will be recruited and be randomly allocated into three parallel groups, receiving either 1) MA-related cues retrieval in VR combined with active TMS (MA VR scene + TBS) or 2) sham TMS (MA VR scene + sham TBS), or 3) neutral cues retrieval in VR combined with active TMS (neutral VR scene + TBS). Two sessions of post-VR-retrieval TBS will be scheduled on two separate days within 1 week. The primary outcome will detect the memory-related activity by the electroencephalography (EEG) reactivity to drug cues in VR scenes. Secondary outcomes are the self-reported MA craving in VR scene, the physiological parameter (cue-induced heart rate) and the scores of psychological questionnaires including anxiety, depression, and mood. All primary and secondary outcomes will be assessed at baseline, 1-week, and 1-month post-intervention. Assessments will be compared between the groups of 1) MA VR scene + TBS, 2) MA VR scene + sham TBS and 3) neutral VR scene + TBS.

Discussion

This will be the first study to examine whether the TMS modulation after VR retrieval can reduce self-reported craving and drug-related cue reactivity. It will promote the understanding of the neural circuit mechanism of the reconsolidation-based intervention and provide an effective treatment for MA use disorder patients.

Clinical Trial Registration

[Chinese Clinical Trial Registry], identifier [ChiCTR1900026902]. Registered on 26 October 2019.

A Pilot Randomized Control Study on Effect Brief Heart Rate Variability Biofeedback as a Complementary Treatment in Men with Methamphetamine Use Disorder

The aims of this study were to investigate the efficacy of heart rate variability biofeedback (HRVBFB) intervention in terms of reducing craving, severity of dependence, and rate of positive methamphetamine urine testing in men taking part in a methamphetamine use disorder outpatient treatment program. Sixty-one adult men received either HRVBFB treatment plus treatment as usual (TAU) over four weeks or TAU only. Men receiving HRVBFB showed significantly greater reductions in craving, dependence severity, and the rate of positive methamphetamine urine testing at the end of the intervention and four weeks of follow-up. The analyses further showed that the levels of craving and dependence severity at treatment entry were predictive of changes in craving and dependence severity at the end of treatment and follow-up, respectively. The baseline status of a positive methamphetamine urine test only predicted a positive methamphetamine urine test at the end of treatment, not at the end of the follow-up period. Our results showed HRVBFB intervention has merits as an adjunct treatment to ameliorate cravings and reduce the severity of dependence experienced by persons with methamphetamine use disorder. An added value of HRVBFB intervention is the fact that it can be easily and affordably implemented in everyday life.

Effects of Transcranial Direct Current Stimulation on Attentional Bias to Methamphetamine Cues and Its Association With EEG-Derived Functional Brain Network Topology

BACKGROUND

Although transcranial direct current stimulation (tDCS) has shown to potentially mitigate drug craving and attentional bias to drug-related stimuli, individual differences in such modulatory effects of tDCS are less understood. In this study, we aimed to investigate a source of the inter-subject variability in the tDCS effects that can be useful for tDCS-based treatments of individuals with methamphetamine (MA) use disorder (IMUD).

METHODS

Forty-two IMUD (all male) were randomly assigned to receive a single-session of either sham or real bilateral tDCS (anodal right/cathodal left) over the dorsolateral prefrontal cortex. The tDCS effect on MA craving and biased attention to drug stimuli were investigated by quantifying EEG-derived P3 (a measure of initial attentional bias) and late positive potential (LPP; a measure of sustained motivated attention) elicited by these stimuli. To assess the association of changes in P3 and LPP with brain connectivity network (BCN) topology, the correlation between topology metrics, specifically those related to the efficiency of information processing, and the tDCS effect was investigated.

RESULTS

The P3 amplitude significantly decreased following the tDCS session, whereas the amplitudes increased in the sham group. The changes in P3 amplitudes were significantly correlated with communication efficiency measured by BCN topology metrics (r = -0.47, P = .03; r = -0.49, P = .02). There was no significant change in LPP amplitude due to the tDCS application.

CONCLUSIONS

These findings validate that tDCS mitigates initial attentional bias, but not the sustained motivated attention, to MA stimuli. Importantly, however, results also show that the individual differences in the effects of tDCS may be underpinned by communication efficiency of the BCN topology, and therefore, these BCN topology metrics may have the potential to robustly predict the effectiveness of tDCS-based interventions on MA craving and attentional bias to MA stimuli among IMUD.

Emotional distress and pain catastrophizing predict cue-elicited opioid craving among chronic pain patients on long-term opioid therapy

BACKGROUND

Individuals who use illicit substances exhibit cue-elicited craving and autonomic cue-reactivity when exposed to cues associated with past drug use. However, little is known about this phenomenon among chronic pain patients on long-term opioid therapy (LTOT). Negative cognitive-emotional reactivity in general (e.g., distress) and cognitive-emotional reactivity specific to pain (e.g., pain catastrophizing) might drive cue-reactivity independent of pain severity. Here we examined emotional distress and pain catastrophizing as predictors of cue-reactivity among a sample of chronic pain patients receiving LTOT. We also tested whether associations between distress, catastrophizing, and cue-reactivity differed as a function of opioid misuse status.

MATERIALS AND METHODS

Patients receiving LTOT (N = 243) were classified as exhibiting aberrant behavior consistent with opioid misuse (MISUSE+, n = 145) or as using opioids as prescribed (MISUSE-, n = 97). Participants completed assessments of pain catastrophizing and emotional distress and then participated in an opioid cue-reactivity task one week later. Cue-elicited opioid craving and autonomic cue-reactivity were measured with craving ratings and high-frequency heart rate variability (HRV), respectively.

RESULTS

Distress and catastrophizing predicted cue-elicited craving and HRV, whereas pain severity did not. Misuser status moderated the relationship between emotional distress and self-reported craving, such that higher levels of distress predicted craving among the MISUSE+ group, but not among the MISUSE- group. No moderating effects were found for catastrophizing.

CONCLUSIONS

Findings suggest that although opioids are prescribed for analgesia, the exacerbating influence of negative cognitive-emotional reactivity, both in general and specific to pain, on cue-elicited opioid craving extends beyond the effects of pain severity alone.

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.

Using Virtual Reality to Induce and Assess Objective Correlates of Nicotine Craving: Paradigm Development Study

Background

Craving is a clinically important phenotype for the development and maintenance of nicotine addiction. Virtual reality (VR) paradigms are successful in eliciting cue-induced subjective craving and may even elicit stronger craving than traditional picture-cue methods. However, few studies have leveraged the advances of this technology to improve the assessment of craving.

Objective

This report details the development of a novel, translatable VR paradigm designed to both elicit nicotine craving and assess multiple eye-related characteristics as potential objective correlates of craving.

Methods

A VR paradigm was developed, which includes three Active scenes with nicotine and tobacco product (NTP) cues present, and three Neutral scenes devoid of NTP cues. A pilot sample (N=31) of NTP users underwent the paradigm and completed subjective measures of nicotine craving, sense of presence in the VR paradigm, and VR-related sickness. Eye-gaze fixation time (“attentional bias”) and pupil diameter toward Active versus Neutral cues, as well as spontaneous blink rate during the Active and Neutral scenes, were recorded.

Results

The NTP Cue VR paradigm was found to elicit a moderate sense of presence (mean Igroup Presence Questionnaire score 60.05, SD 9.66) and low VR-related sickness (mean Virtual Reality Sickness Questionnaire score 16.25, SD 13.94). Scene-specific effects on attentional bias and pupil diameter were observed, with two of the three Active scenes eliciting greater NTP versus control cue attentional bias and pupil diameter (Cohen d=0.30-0.92). The spontaneous blink rate metrics did not differ across Active and Neutral scenes.

Conclusions

This report outlines the development of the NTP Cue VR paradigm. Our results support the potential of this paradigm as an effective laboratory-based cue-exposure task and provide early evidence of the utility of attentional bias and pupillometry, as measured during VR, as useful markers for nicotine addiction.

Study protocol-Evoked craving in high-dose benzodiazepine users

Benzodiazepine (BDZ) abuse, especially concerning high doses of BDZs, is an impairing substance use disorder (SUD) that is often difficult to treat. Craving and cue reactivity (CR) are two important phenomena that have a prominent role in maintaining addiction and triggering relapses in BDZ abuse; nevertheless, they have rarely been addressed in scientific literature. The present study aims to fill these gaps by implementing a highly innovative virtual reality (VR) design to assess the impact of substance-related environmental cues on BDZ craving, as well as their influence on patients' affective states. Therefore, on one hand, this research will contribute to the assessment of VR feasibility in the study of these phenomena, and, on the other, it will help disentangle the role that CR and craving have on mood and attention, which are equally important factors to consider when treating SUDs. We will recruit a healthy control group and a patient group comprising people seeking treatment for BDZ detoxification. The experimental design will consist of the presentation of three VR scenarios, one neutral, one BDZ-related but without BDZ cues, and another with BDZ cues. The craving will be measured through a virtual analog scale (VAS); the Profile of Mood States (POMS) and Alcohol Attention Scale (AAS) questionnaires in a modified version will also be administered. We will additionally control for VR-induced feelings of sickness by administering the Simulator Sickness Questionnaire (SSQ), and the Presence Questionnaire (PQ) will be used to investigate participants' sense of presence in virtual environments. We expect patients to exhibit higher levels of craving, and that the craving will be higher after exposure to a cue-related virtual environment as compared to a neutral scenario.

Assessing methamphetamine-related cue reactivity in people with methamphetamine use disorder relative to controls

Methamphetamine use disorder involves methamphetamine-related cues invoking intense craving leading to relapse. Such cue reactivity is thought to arise from Pavlovian conditioning that occurs during the drug-taking experience. Cue reactivity then should be selective to methamphetamine cues (and not other cues), and not observed in people who have never experienced methamphetamine. However, these premises have never been tested and reported using objective measures such as skin conductance response (SCR). The primary aim of this study was to test these premises using a cue reactivity paradigm we developed using control cues. The secondary aim was to explore the relationship between cue reactivity, drug use characteristics, and cognition. Thirty people with a current diagnosis of methamphetamine use disorder and 30 matched controls with no history of substance use disorder were recruited. We observed higher overall subjective reactivity (F = 62.810; p < 0.001) and cue-selective physiological reactivity (F = 5.160; p = 0.026) in people with methamphetamine use disorder but not in controls. Co-morbid sedative use was associated with higher subjective craving (r = 0.521; p = 0.003). People who use methamphetamine intravenously had higher cue-selective SCR than smokers (t = 3.750; p < 0.001). Low inhibitory control measured by the Stroop task was associated with increased craving across the cue paradigm (r = -0.494; p = 0.006). Overall, these results support that cue reactivity in people with methamphetamine use disorder is due to Pavlovian conditioning. Its association with drug use and cognition highlights cue reactivity paradigm's utility in understanding methamphetamine use disorder to develop new treatments targeting cue-induced craving.

Virtual Reality-Based Treatment Approaches in the Field of Substance Use Disorders

Purpose

Substance use disorders (SUD) are burdening chronic conditions characterized by high relapse rates despite severe negative consequences. Substance-related cues that elicit craving by means of automatic physiological and behavioural responses have long been suggested to predict relapse. One major mechanism contributing to relapse behaviour are cue-induced behavioural approach tendencies towards the addictive agent. Recently, there has been an emerging interest in virtual reality (VR)-based approaches to assess and modify craving and its related responses. This review aims at elucidating (1) VR techniques applied in the field of SUD, (2) VR as an induction/assessment tool for biopsychological correlates of craving and (3) VR-based therapeutic approaches.

Findings

There is an emerging number of studies focusing on different substances of abuse incorporating VR in craving induction/assessment as well as therapy. Despite some limitations as missing of randomized controlled clinical trials with large samples and missing data on the long-term effects of VR treatment, the VR approach showed consistent results in eliciting and reducing craving across different substances.

Summary

This review suggests virtual reality as a promising tool for the assessment and treatment of craving among individuals with substance use disorders. Because of its ecological validity, VR unifies the benefits of a laboratory setting with the advantages of a realistic environment. Further studies with large samples and randomized controlled clinical trials using more homogenous VR techniques as well as assessment of objective biophysiological craving markers are required.

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.

Craving for Ketamine and Its Relationship With Clinical Outcome Indicators in Males With Ketamine Use Disorder

Background: Craving is considered a hallmark of substance use disorder and is one of the criteria of substance use disorder. The Desires for Drug Questionnaire (DDQ) is a widely used questionnaire to assess craving for heroin. This study aimed to examine the psychometric properties of the ketamine version of the DDQ (DDQ-K) and the associations between craving for ketamine as measured using the DDQ-K and clinical outcome indicators in individuals with ketamine use disorder. Methods: In total, 651 individuals with ketamine use disorder completed the DDQ-K and the Visual Analog Craving Scale (VACS). Demographic data, severity of ketamine use, money spent on ketamine, positive/negative aspects of ketamine use, and readiness to change ketamine use were also recorded. We examined the reliability (internal consistency), construct validity (factor structure), and concurrent validity of the DDQ-K. Multiple regression analysis was used to examine the relationships of craving measured using the DDQ-K with clinical outcome indicators, including money spent on ketamine, severity of ketamine use, positive/negative aspects of ketamine use, and readiness to change ketamine use. Results: The original three-factor model of the DDQ-K was acceptable for use in individuals with ketamine use disorder according to confirmatory factor analysis. The subscales of Desire and Intention and Negative Reinforcement of the DDQ-K, but not the subscale of Control, were of acceptable concurrent validity. The score on the Desire and Intention subscale was positively associated with the level of ketamine dependence, money spent on ketamine use, and positive/negative aspects of ketamine use and negatively associated with readiness to change ketamine use. Conclusion: This study supported the use of the Desire and Intention and Negative Reinforcement subscales of the DDQ-K to assess craving in patients with ketamine use.

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.

Add-on repetitive transcranial magnetic stimulation in patients with opioid use disorder undergoing methadone maintenance therapy

Background: Repetitive transcranial magnetic stimulation (rTMS) shows potential therapeutic effects for individuals with addiction, but few studies have examined individuals with opioid use disorder (OUD).Objectives: We conducted an add-on double-blinded, sham-controlled rTMS feasibility pilot trial to examine OUD participants undergoing methadone maintenance therapy (MMT). The current report focused on the effects of rTMS on (1) craving and heroin use behavior and (2) depression, impulsivity, and attention.Methods: Active or sham rTMS treatment was applied to the left dorsolateral prefrontal cortex (DLPFC) over a total of 11 sessions in 4 weeks (15-Hz frequency, 4 seconds per train, intertrain interval of 26 seconds, 40 trains per session) in OUD participants (ClinicalTrials.gov registration number: NCT03229642). Craving, heroin use severity, urine morphine tests, the Hamilton Depression Rating Scale (HDRS), the Barratt Impulsiveness Scale-11 (BIS-11), and the Continuous Performance Tests (CPTs) were measured.Results: Twenty-two OUD participants were enrolled, of which eleven (8 males) were undergoing active rTMS and nine (8 males) were in the sham rTMS group. After 12 weeks of follow-up, the active rTMS group did not show significantly greater improvements than the sham group with respect to craving, heroin use, or urine morphine test results. However, HDRS scores, BIS-11 attentional subscales, and CPTs commission T-scores (C-TS) were significantly lower in the active rTMS group (P = .003, 0.04, and 0.02, respectively) than in the sham group.Conclusion: Add-on rTMS did not appear to improve heroin use behavior but may have benefitted depressive symptoms, impulse control and attention in OUD participants undergoing MMT.

Virtual Reality (VR) Applications in Cardiology: A Review

Virtual reality (VR) has applications in cardiology to create enhancement, thereby improving the quality of associated planning, treatment and surgery. The need is to study different applications of this technology in the field of cardiology. We have studied research papers on VR and its applications in cardiology through a detailed bibliometric analysis. The study identified five significant steps for proper implementation of this technology in cardiology. Some challenges are to be undertaken by using this technology, and they can provide some benefits; thus, authors contemplate extensive research and development. This study also identifies 10 major VR technology applications in cardiology and provided a brief description. This innovative technology helps a heart surgeon to perform complex heart surgery effectively. Thus, VR applications have the potential for improving decision-making, which helps save human life. VR plays a significant role in the development of a surgical procedure. This technology undertakes 3D heart model information in full colour, which helps to analyze the overall heart vane, blockage and blood flow. With the help of this digital technology, a surgeon can improve the accuracy of heart surgery, and he can simulate the surgery. A surgeon can undertake surgery in a virtual environment on a virtual patient. The unique purpose of this technology is to practice pre-operatively on the specific circumstance. A cardiologist can also check the proper status of inner and outer heart wall layer. Thus, by using this 3D information, the surgeon can now interact with heart data/information without any physical touch. This technology opens a new opportunity to improve the heart surgery and development in cardiovascular treatment to improve patient outcome.

Craving and implicit attitude toward heroin use and their relationships with the levels of heroin dependence and methadone adherence in heroin users

Craving is a core feature of heroin use disorder. Craving for heroin is a conscious cognitive process. Recently, implicit (i.e., an implicit attitude toward heroin use) cognitive processes have been thought to be precursors of cravings. This study aimed to explore the associations of craving and implicit attitude toward heroin use with the level of heroin use disorder and adherence to methadone maintenance treatment (MMT). This study recruited 213 intravenous heroin users (196 males and 17 females) from MMT clinics of two hospitals. The mean age of participants was 42.3 years. They provided details of their severity of heroin use disorder and craving for heroin via questionnaires and also completed a computerized test to assess implicit attitude toward heroin use. The relationships between implicit attitude, craving, age, heroin use disorder, and MMT adherence were examined using path analysis. Craving was positively related to heroin use disorder (beta = 0.4). Implicit attitude directly and indirectly positively contributed to heroin use disorder (betas: 0.1 and 0.3). Craving was positively related to MMT adherence (beta: 0.2), whereas implicit attitude had an indirect effect on MMT adherence (beta: 0.03). Age was negatively associated with craving but was not associated with implicit attitude toward heroin. Methadone dosage was negatively associated with craving. Craving is significantly associated with the levels of heroin use disorder and MMT adherence. Meanwhile, craving mediates the relationship between implicit attitude and heroin use disorder, as well as MMT adherence. Implicit attitude also contributes to the level of heroin use disorder directly. For reducing craving, adequate dosage may be necessary.

An Intelligent Virtual-Reality System With Multi-Model Sensing for Cue-Elicited Craving in Patients With Methamphetamine Use Disorder

Methamphetamine abuse is getting worse amongst the younger population. While there is methadone or buprenorphine harm-reduction treatment for heroin addicts, there is no drug treatment for addicts with methamphetamine use disorder (MUD). Recently, non-medication treatment, such as the cue-elicited craving method integrated with biofeedback, has been widely used. Further, virtual reality (VR) is proposed to simulate an immersive virtual environment for cue-elicited craving in therapy. In this study, we developed a VR system equipped with flavor simulation for the purpose of inducing cravings for MUD patients in therapy. The VR system was integrated with multi-model sensors, such as an electrocardiogram (ECG), galvanic skin response (GSR) and eye tracking to measure various physiological responses from MUD patients in the virtual environment. The goal of the study was to validate the effectiveness of the proposed VR system in inducing the craving of MUD patients via the physiological data. Clinical trials were performed with 20 MUD patients and 11 healthy subjects. VR stimulation was applied to each subject and the physiological data was measured at the time of pre-VR stimulation and post-VR stimulation. A variety of features were extracted from the raw data of heart rate variability (HRV), GSR and eye tracking. The results of statistical analysis found that quite a few features of HRV, GSR and eye tracking had significant differences between pre-VR stimulation and post-VR stimulation in MUD patients but not in healthy subjects. Also, the data of post-VR stimulation showed a significant difference between MUD patients and healthy subjects. Correlation analysis was made and several features between HRV and GSR were found to be correlated. Further, several machine learning methods were applied and showed that the classification accuracy between MUD and healthy subjects at post-VR stimulation attained to 89.8%. In conclusion, the proposed VR system was validated to effectively induce the drug craving in MUD patients.

Peripheral Inflammatory Biomarkers of Methamphetamine Withdrawal Patients Based on the Neuro-Inflammation Hypothesis: The Possible Improvement Effect of Exercise

Methamphetamine (MA) induced addiction and neuroinflammation has been implicated. Based on the neuroinflammation hypothesis, this study aims to investigate how exercise influences the craving of patients in MA withdrawal, and explore the mechanism of peripheral inflammation. A total of 90 patients in MA withdrawal were recruited. No difference was noted in the number of years of drug use and the frequency of drug use among patients, and the withdrawal time was within 2 months. The subjects were grouped based on the degree of craving induced by the cues: non-craving control group (NCC group), craving control group (CC group), and craving exercise group (CE group). The CE group was subjected to aerobic combined resistance training. Then, the ELISA method was used to detect plasma IL-6, TNF-α, and IL-1β concentrations; Visual Analog Scale (VAS) measurement of cue-induced cravings under Virtual Reality (VR) exposure (VR-VAS) and the Desires for Drug Questionnaire (DDQ) were used to assess cravings. Consequently, plasma IL-6, TNF-α, IL-1β, levels, and the VR-VAS and DDQ scores of MA withdrawal patients were significantly reduced after exercise. This study confirmed that 8 weeks of incremental load aerobic combined with resistance training reduces peripheral inflammation and significantly reduces the level of craving for MA.

Sleep quality among individuals with ketamine use and the mediating role of craving

Sleep problems are common in Taiwan. Poor sleep may be associated with many illnesses, including substance use disorders. Ketamine use disorder has significantly increased in Taiwan in recent years and may lead to physical and cognitive problems. Craving for ketamine is a risk factor for ketamine use and relapse, and poor sleep quality may increase craving. This study aimed to explore the mediating effects of craving on the relationship between poor sleep quality and ketamine use. Demographic data, sleep quality, severity of dependence and craving were recorded for current ketamine users and abstinent ketamine users. Mediation analysis was used to examine the mediating effect of craving on the relationship between poor sleep and ketamine use. This study enrolled 414 current ketamine users with ketamine use disorder, 238 current ketamine users without ketamine use disorder, and 102 abstinent ketamine users with ketamine use disorder. Compared with healthy controls, all ketamine users had poor sleep quality. Poor sleep quality was associated with the initiation of and dependence on ketamine use. Craving can mediate the relationship between poor sleep quality and ketamine use. Poor sleep quality remains a problem for those abstaining from ketamine use. Poor sleep quality in ketamine users is an important issue because it is directly and indirectly through craving associated with ketamine use.

Using machine-learning approach to distinguish patients with methamphetamine dependence from healthy subjects in a virtual reality environment

BACKGROUND

The aim of this study was to evaluate whether machine learning (ML) can be used to distinguish patients with methamphetamine dependence from healthy controls by using their surface electroencephalography (EEG) and galvanic skin response (GSR) in a drug-simulated virtual reality (VR) environment.

METHODS

A total of 333 participants with methamphetamine (METH) dependence and 332 healthy control subjects were recruited between January 2018 and January 2019. EEG (five electrodes) and GSR signals were collected under four VR environments: one neutral scenario and three METH-simulated scenarios. Three ML classification techniques were evaluated: random forest (RF), support vector machine (SVM), and logistic regression (LR).

RESULTS

The MANOVA showed no interaction effects among the two subject groups and the 4 VR scenarios. Taking patient groups as the main effect, the METH user group had significantly lower GSR, lower EEG power in delta (p < .001), and alpha bands (p < .001) than healthy subjects. The EEG power of beta band (p < .001) and gamma band (p < .001) was significantly higher in METH group than the control group. Taking the VR scenarios (Neutral versus METH-VR) as the main effects, the GSR, EEG power in delta, theta, and alpha bands in neutral scenario were significantly higher than in the METH-VR scenario (p < .001). The LR algorithm showed the highest specificity and sensitivity in distinguishing methamphetamine-dependent patients from healthy controls.

CONCLUSION

The study shows the potential of using machine learning to distinguish methamphetamine-dependent patients from healthy subjects by using EEG and GSR data. The LR algorithm shows the best performance comparing with SVM and RF algorithm.

A Scoping Review on Cue Reactivity in Methamphetamine Use Disorder

The experience of craving via exposure to drug-related cues often leads to relapse in drug users. This study consolidated existing empirical evidences of cue reactivity to methamphetamine to provide an overview of current literature and to inform the directions for future research. The best practice methodological framework for conducting scoping review by Arkey and O'Malley was adopted. Studies that have used a cue paradigm or reported on cue reactivity in persons with a history of methamphetamine use were included. Databases such as Medline, EMBASE, PsycINFO and CINAHL were searched using key terms, in addition to citation check and hand search. The search resulted in a total of 32 original research articles published between 2006 to 2020. Three main themes with regard to cue reactivity were identified and synthesized: (1) effects of cue exposure, (2) individual factors associated with cue reactivity, and (3) strategies that modulate craving or reactivity to cues. Exposure to methamphetamine-associated cues elicits significant craving and other autonomic reactivity. Evidence suggests that drug cue reactivity is strongly associated with indices of drug use and other individual-specific factors. Future studies should focus on high quality studies to support evidence-based interventions for reducing cue reactivity and to examine cue reactivity as an outcome measure.

Memory Retrieval-Extinction Combined With Virtual Reality Reducing Drug Craving for Methamphetamine: Study Protocol for a Randomized Controlled Trial

BACKGROUND

Relapse, often precipitated by drug-associated cues that evoke craving, is a key problem in the treatment of methamphetamine use disorder (MUD). Drug-associated memories play a major role in the maintenance of relapse. Extinction training is a common method for decreasing drug craving by suppressing drug-associated memories. However, the effects are often not permanent, which is evident in form of spontaneous recovery or renewal of cue-elicited responses. Based on memory reconsolidation theory, the retrieval-extinction (R-E) paradigm may be more effective in decreasing spontaneous recovery or renewal responses than extinction. After the original memory reactivated to a labile state, extinction will be introduced within the reconsolidation window, thereby updating drug-associated memories. However, there are still some controversial results, which suggest that the reactivation of drug-associated memories and the 10 min-6 h of limited time window are two main elements in the R-E protocol. Virtual reality (VR) is supposed to promote memory reactivation by providing vivid drug-related stimuli when compared with movies.

OBJECTIVE

The aim of this study is to examine the effectiveness of R-E training combined with VR on reducing spontaneous recovery or renewal of cue-elicited responses, in comparison to extinction, R-E training provided outside the time window of 6 h and R-E training retrieved using videos, in methamphetamine abusers.

METHODS

The study is a parallel matched controlled study including 95 participants with MUD. Participants will be randomly assigned to either a R-10 min-E group (methamphetamine-related cues retrieval in VR followed by extinction after 10 min) or a NR-10 min-E group (neutral cues retrieval in VR followed by extinction after 10 min) or a R-6 h-E group (methamphetamine-related cues retrieval in VR followed by extinction after 6 h) or a RV-10 min-E group (methamphetamine-related cues retrieval in videos followed by extinction after 10 min). Cue-evoked craving and reactivity will be assessed at pre-test and at 1 day, 1 week, 1 month, and 6-month post-tests.

DISCUSSION

To our knowledge, this study will probably be the first study to examine the efficacy of R-E training combined with VR to reduce cue-evoked responses in people with MUD. This innovative non-pharmacological intervention targeting drug-associated memories may provide significant clinical implications for reducing relapse, providing the study confirms its efficacy.

CLINICAL TRIAL REGISTRATION

The trial is registered with Chinese Clinical Trial Registry at 17 October 2018, number: ChiCTR1800018899, URL: http://www.chictr.org.cn/showproj.aspx?proj=30854.

Augmented and Virtual Reality Evolution and Future Tendency

Augmented reality and virtual reality technologies are increasing in popularity. Augmented reality has thrived to date mainly on mobile applications, with games like Pokémon Go or the new Google Maps utility as some of its ambassadors. On the other hand, virtual reality has been popularized mainly thanks to the videogame industry and cheaper devices. However, what was initially a failure in the industrial field is resurfacing in recent years thanks to the technological improvements in devices and processing hardware. In this work, an in-depth study of the different fields in which augmented and virtual reality have been used has been carried out. This study focuses on conducting a thorough scoping review focused on these new technologies, where the evolution of each of them during the last years in the most important categories and in the countries most involved in these technologies will be analyzed. Finally, we will analyze the future trend of these technologies and the areas in which it is necessary to investigate to further integrate these technologies into society.

A virtual reality counterconditioning procedure to reduce methamphetamine cue-induced craving

The present work developed a virtual reality (VR) counterconditioning procedure (VRCP), and investigated its efficacy in treatment of cue-induced craving in individuals with methamphetamine (METH) dependence. In study 1, thirty-one patients diagnosed with METH dependence received VRCP, while twenty-nine METH-dependent patients in waiting-list group did not. In study 2, the VRCP was computerized as a VR treatment system. Six-hundred and twelve abstinent individuals with a history of METH dependence received the computerized VRCP, while two-hundred seventy-six abstinent individuals with a history of METH dependence in waiting-list group did not. Patients with METH dependence who received VRCP showed a significantly larger decrease on the score of METH-craving and METH-liking from baseline to follow-up assessments, compared to those who did not received VRCP. Participants received VRCP showed a significantly larger decrease in HRV indexes on time domain and non-linear domain from baseline to follow-up assessments during exposure to VR cues, compared to those in waiting-list group. These findings indicate that the counterconditioning procedure under VR environment may be a useful strategy in suppressing cue-induced reactivity for patients with METH dependence.

Methamphetamine-associated psychosis: Clinical presentation, biological basis, and treatment options

INTRODUCTION

Methamphetamine associated psychosis (MAP) represents a mental disorder induced by chronic methamphetamine use in a subset of users. The prevalence of the disorder has increased in several countries in Europe and Asia where methamphetamine use has increased. MAP remains difficult to distinguish from primary psychiatric disorders, especially schizophrenia, creating complications in prescribing treatment plans to patients.

DESIGN

This narrative review sought to summarize difficulties related to MAP diagnosis and highlight the need for a better treatment model. Current best practices are described and potential novel therapies and future research suggested.

RESULTS

Results suggest that clear biological and clinical differences appear between patients presenting with MAP and schizophrenia and that there may exist distinct subgroups within MAP itself. MAP-specific treatment studies have been few and have focused on the use of antipsychotic medication. Antipsychotic treatment has been shown to alleviate the psychotic symptoms of MAP but produce debilitating adverse effects and fail to adequately address methamphetamine use in patients.

CONCLUSIONS

Continued identification of subgroups within the heterogenous MAP population may lead to better diagnosis, treatment, and outcomes for patients. Psychosocial therapies should be explored in addressing the cooccurring substance use and psychosis in the treatment of MAP.

Cue-Elicited Anxiety and Alcohol Craving as Indicators of the Validity of ALCO-VR Software: A Virtual Reality Study

BACKGROUND

This study is part of a larger project aiming to develop a virtual reality (VR) software to be implemented as a clinical tool for patients diagnosed with alcohol use disorder (AUD). The study is based on previous research in which we identified factors that elicit craving for alcohol in a sample of AUD patients, and which led to the development of a virtual reality software to be used in cue exposure treatments of alcohol use disorder (ALCO-VR). The main objective of this study was to test the effectiveness of ALCO-VR to elicit cue-induced craving and anxiety responses among social drinkers (SD) and AUD patients. Our secondary objective was to explore which responses (cue-induced craving or anxiety) can best differentiate between AUD patients and the SD group.

METHOD

Twenty-seven individuals (13 AUD patients and 14 SD) participated in this study after giving written informed consent. Their anxiety and alcohol craving levels were measured by different instruments at different stages of the procedure. The VR equipment consisted of Oculus Rift technology, and the software consisted of the ALCO-VR platform.

RESULTS

Our data indicate that the ALCO-VR software can elicit responses of anxiety and alcohol craving, especially in the group of AUD patients. The cue-induced anxiety response differentiated AUD patients and the SD group better than the cue-induced craving response.

CONCLUSIONS

The general interest in applying new technologies to the assessment and treatment of mental health disorders has led to the development of immersive real-life simulations based on the advantages of VR technology. Our study concluded that the ALCO-VR software can elicit anxiety and craving responses and that cue-induced anxiety responses can distinguish between AUD and SD groups better than cue-induced craving. The data on craving and anxiety were assessed consistently by different instruments. In addition, we consider that ALCO-VR is able to ecologically assess cue-induced anxiety and alcohol craving levels during exposure to VR alcohol-related environments.

The training game SALIENCE for the therapy of alcohol use disorder

The feasibility study was aimed to develop a web-based gaming tool for the therapy of alcohol use disorder to offer patients a cue-exposure-based extinction and decision training, enhanced with virtual reality. To increase the training effect, patients playfully experience situations that resemble critical real-life situations. For implementing the game, a combination of HTML5 and JavaScript was used. The application comes with an administrator interface, to allow editing the game content. Initially, we included 21 patients (Group 1), 18 suffering from alcohol use disorder and 3 using cannabis (18/3 male/female, mean age 39 ± 13 years). Considering the iterative process of a feasibility study, we developed the game design as suggested by participants of Group 1 and additionally included 11 novel participants (Group 2) (11 suffering from an alcohol use disorder, 7/4 male/female, mean age 46 ± 14 years). Basically, the game was very well received. Usability ratings were generally high, even in patients with little computer experience. Both groups rated the application as realistic, and would generally be willing to play it on a daily basis. Given that SALIENCE is inexpensive, easily available, and engaging, it might be a reasonable add-on intervention to the standard treatment of alcohol use disorder.

Identifying Triggers of Alcohol Craving to Develop Effective Virtual Environments for Cue Exposure Therapy

Background: Many studies have indicated that alcohol craving is a core mechanism in the acquisition, maintenance, and precipitation of relapse in alcohol use disorder (AUD). A common treatment approach in AUD is cue exposure therapy (CET). New technologies like virtual reality (VR) have the potential to enhance the effectiveness of CET by creating realistic scenarios in naturalistic environments. In this study, we aimed to determine relevant triggers of alcohol craving in patients with AUD.

Methods: We enrolled 75 outpatients diagnosed with AUD according to the DSM-5 criteria Participants completed the Alcohol Use Disorder Identification Test and a self-administered questionnaire to assess alcohol craving. The variables included in the craving questionnaire were as follows: presence of others, situations, time of the day, day of the week, mood, and type of alcoholic beverage.

Results: Greater levels of alcohol craving were seen in many situations, including being at a party, in a restaurant, in a bar or pub, and at home. Drinking alone and drinking with two or more friends were equally associated with higher levels of craving. Drinking at night and drinking at weekends also emerged as triggers for alcohol craving. Emotional states like anxiety or tension, sadness, stress, frustration, or irritability were highly associated with urges to drink alcohol. The alcoholic drinks most highly associated with increased levels of craving were beer, wine, and whisky. Gender and age implications were discussed.

Conclusion: This study is part of a larger project aiming to develop and validate CET based on VR technology for patients with AUD who are resistant to classical treatment. The identified triggers have been used to develop relevant VR environments for CET, and further research is ongoing to implement our findings.

Detection of patients with methamphetamine dependence with cue-elicited heart rate variability in a virtual social environment

In the present study, we developed a methamphetamine (METH)-related virtual social environment to elicit subjective craving and physiological reactivity. Sixty-one male patients who were abstinent from METH use and 45 age-matched healthy males (i.e., normal controls) were recruited. The physiological electrocardiogram (ECG) signals were recorded before (resting-state condition) and during viewing of a METH-cue video in the virtual environment (cue-induced condition). The cue-induced subjective craving was measured with a visual analogue scale (VAS) for patients with METH dependence. The results indicated that the cue-induced condition elicited significant differences in heart rate variability (HRV) between patients with METH dependence and normal controls. The changes of HRV indexes on time domain and non-linear domain from the resting-state condition to the cue-induced condition were positively correlated with the score on VAS of METH craving. Using a supervised machine learning algorithm with the features extracted from HRV changes, our results showed that the discriminant model provided a high predictive power for distinguishing patients with METH dependence from normal controls. Our findings support that immersing subjects with METH dependence in a METH-related virtual social environment can successfully induce physiological reactivity, and cue-induced physiological signal changes may have a potential implication in clinical practice.

Cardiac vagal dysfunction moderates patterns of craving across the day in moderate to heavy consumers of alcohol

Background

Alcohol craving, a known correlate of vulnerability to Alcohol Use Disorder (AUD), has been found to be inversely related to cardiac vagal tone (CVT). Here we examine how resting CVT, CVT reactivity to a postural challenge, and their interaction influence craving during imposed alcohol abstinence and their usual drinking among moderate to heavy drinkers.

Methods

Participants were recruited from the local community (final n = 29) and assessed for CVT functioning via respiratory sinus arrhythmia (RSA) at rest (RSA-rest) and during a postural challenge (RSA-react). Craving intensity was assessed throughout the day during 3-day periods of imposed alcohol abstinence (abstained days) and drinking as usual (normal days) via Ecological Momentary Assessment (EMA). Multilevel statistical modeling assessed relationships between patterns of CVT and diurnal craving. The primary hypothesis of interest was that the interaction of RSA-rest with RSA-react would be significantly associated with increased craving across the day.

Results

Overall, craving increased throughout the day and significantly decreased after drinking (p < 0.001). There was a significant interaction between RSA-rest and RSA-react with plots revealing that this effect was driven by an aberrant craving pattern among participants with higher RSA-rest and a sluggish vagal brake in response to a postural shift—atypical RSA-react.

Conclusion

Although additional research is needed to corroborate these findings, our results suggest that moderate-heavy drinkers characterized by higher RSA-rest and atypical RSA-react exhibit aberrant patterns of craving across the day that may represent a risk factor for AUD.

Prescription opioid misusing chronic pain patients exhibit dysregulated context-dependent associations: Investigating associative learning in addiction with the cue-primed reactivity task

BACKGROUND

Associative learning undergirds the development of addiction, such that drug-related cues serve as conditioned stimuli to elicit drug-seeking responses. Plausibly, among opioid misusing chronic pain patients, pain-related information may serve as a conditioned stimulus to magnify opioid cue-elicited autonomic and craving responses through a process of second-order conditioning.

METHODS

We utilized a novel psychophysiological probe of pain-opioid conditioned associations, the Cue-Primed Reactivity (CPR) task. In this task, participants were presented with images as primes (200 ms) and cues (6000 ms) in pairs organized in four task blocks: "control-opioid," "pain-opioid," "control-pain," and "opioid-pain." Opioid-treated chronic pain patients (N = 30) recruited from an Army base in the Western United States were classified as opioid misusers (n = 17) or non-misusers (n = 13) via a validated cutpoint on the Prescription Drug Use Questionnaire (PDUQ; Compton et al., 2008). Opioid misuse status was examined as a predictor of HRV, craving, and mood responses on the CPR task.

RESULTS

HRV increased to a greater extent during the pain-opioid block compared to the control-opioid block for non-misusers compared to misusers (p = .003, η²_partial = 0.27). In contrast, craving increased to a greater extent from baseline to the pain-opioid block for misusers than for non-misusers (p = .03, η²_partial = .16).

CONCLUSIONS

Findings suggest that opioid-treated chronic pain patients exhibit Pavlovian conditioned responses to opioid cues strengthened by an associative learning process of second-order conditioning when primed by pain-related images. This pain-opioid contingency appears to become disrupted among individuals who engage in opioid misuse, such that opioid-related stimuli elicit motivational responses irrespective of pain-related contextual stimuli.

A novel approach of substitution therapy with inhalation of essential oil for the reduction of inhalant craving: A double-blinded randomized controlled trial

Inhalants, which are neurotoxic central nervous system (CNS) suppressants, are frequently abused by young adults. Unlike other CNS depressants, including alcohol and opiates, no treatment is currently approved for inhalant dependence. In this report, a novel approach of substitution treatment for inhalant addiction was explored in a double-blinded, randomized, controlled crossover design to examine the effects of inhalation of essential oil and perfume on the reduction of cue-induced craving for inhalant in thirty-four Thai males with inhalant dependence. The craving response was measured by the modified version of Penn Alcohol Craving Score for Inhalants (PACS-inhalants). The participants (mean age ± SE = 27.9 ± 1.4) in this trial had used inhalant for 5.8 ± 1.1 years. Cravings could be induced in all participants by visual cues as assessed by ^50% increases in inhalant craving levels. Generalized estimating equations showed a significant suppressant effect of essential oil, but not perfume, on the craving response as compared with baseline cue-induced craving. Moreover, essential oil, but not perfume, had significant effects on physiological responses including decreasing pulse rate. It is concluded that inhaling essential oil as a substitution treatment for inhalant may be used as part of treatment programs for reducing inhalant craving.

Computer tool to evaluate the cue reactivity of chemically dependent individuals

BACKGROUND AND OBJECTIVE

Anxiety is one of the major influences on the dropout of relapse and treatment of substance abuse treatment. Chemically dependent individuals need (CDI) to be aware of their emotional state in situations of risk during their treatment. Many patients do not agree with the diagnosis of the therapist when considering them vulnerable to environmental stimuli related to drugs. This research presents a cue reactivity detection tool based on a device acquiring physiological signals connected to personal computer. Depending on the variations of the emotional state of the drug addict, alteration of the physiological signals will be detected by the computer tool (CT) which will modify the displayed virtual sets without intervention of the therapist.

METHODS

Developed in 3ds Max® software, the CT is composed of scenarios and objects that are in the habit of marijuana and cocaine dependent individual's daily life. The interaction with the environment is accomplished using a Human-Computer Interface (HCI) that converts incoming physiological signals indicating anxiety state into commands that change the scenes. Anxiety was characterized by the average variability from cardiac and respiratory rate of 30 volunteers submitted stress environment situations. To evaluate the effectiveness of cue reactivity a total of 50 volunteers who were marijuana, cocaine or both dependent were accompanied.

RESULTS

Prior to CT, the results demonstrated a poor correlation between the therapists' predictions and those of the chemically dependent individuals. After exposure to the CT, there was a significant increase of 73% in awareness of the risks of relapse.

CONCLUSION

We confirmed the hypothesis that the CT, controlled only by physiological signals, increases the perception of vulnerability to risk situations of individuals with dependence on marijuana, cocaine or both.