Location and longing: the nicotine craving experience in virtual reality

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.

Virtual reality: a powerful technology to provide novel insight into treatment mechanisms of addiction

Due to its high ecological validity, virtual reality (VR) technology has emerged as a powerful tool for mental health research. Despite the wide use of VR simulations in research on mental illnesses, the study of addictive processes through the use of VR environments is still at its dawn. In a systematic literature search, we identified 38 reports of research projects using highly immersive head-mounted displays, goggles, or CAVE technologies to provide insight into treatment mechanisms of addictive behaviors. So far, VR research has mainly addressed the roles of craving, psychophysiology, affective states, cognition, and brain activity in addiction. The computer-generated VR environments offer very realistic, dynamic, interactive, and complex real-life simulations requesting active participation. They create a high sense of immersion in users by combining stereoscopic three-dimensional visual, auditory, olfactory, and tactile perceptions, tracking systems responding to user movements, and social interactions. VR is an emerging tool to study how proximal multi-sensorial cues, contextual environmental cues, as well as their interaction (complex cues) modulate addictive behaviors. VR allows for experimental designs under highly standardized, strictly controlled, predictable, and repeatable conditions. Moreover, VR simulations can be personalized. They are currently refined for psychotherapeutic interventions. Embodiment, eye-tracking, and neurobiological factors represent novel future directions. The progress of VR applications has bred auspicious ways to advance the understanding of treatment mechanisms underlying addictions, which researchers have only recently begun to exploit. VR methods promise to yield significant achievements to the addiction field. These are necessary to develop more efficacious and efficient preventive and therapeutic strategies.

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.

A Meta-Analysis of Cue Reactivity in Tobacco Cigarette Smokers

INTRODUCTION

The cue reactivity paradigm allows for systematic evaluation of motivational responses to drug-related cues that may elicit drug use. The literature on this topic has grown substantially in recent decades, and the methodology used to study cue reactivity has varied widely across studies. The present research provided a meta-analytic investigation of variables that have an impact on cue reactivity effects to enhance our understanding of this key feature of tobacco use disorders.

METHODS

A total of 128 publications yielded 249 effect sizes, which were analyzed to investigate the magnitude of the cue reactivity effect and potential moderators.

RESULTS

Craving generated a moderate-to-large effect size (Hedges' g = 0.71, p < .001), indicating that drug cues produced significantly greater craving than neutral cues. However, physiological variables yielded significantly lower or nonsignificant effect sizes. Analyses of a variety of empirically and theoretically relevant moderator variables showed that cue modality, cue personalization, cue reactivity environment, and the use of multiple assessments of cue reactivity were significantly associated with the magnitude of cue-specific craving effects (ps < .001). Effect sizes were not significantly related to abstinence status, gender, cigarettes per day, and treatment-seeking status.

CONCLUSIONS

The results underscored the strength of self-reported craving as an index of cue reactivity across studies, which support theories that posit cue reactivity is core to the addictive process for daily tobacco cigarette smokers. The present research further elucidates the variables that alter the cue reactivity effects across studies and provides recommendations for future cue reactivity research.

IMPLICATIONS

A core feature of addiction is that drug-related cues can have a major impact on motivational responses across multiple substance use disorders, including tobacco cigarettes. This paper describes a meta-analysis updating and synthesizing cue reactivity research with tobacco cigarette smokers over the last 20 years, a time of rapid growth for this literature. The study leads to a better understanding of the cue reactivity paradigm across different self-report and physiological variables and identifies factors that may modulate addictive motivation for tobacco cigarettes.

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.

Virtual Reality (VR) in Assessment and Treatment of Addictive Disorders: A Systematic Review

Background: Substance Use Disorder (SUD) and behavioral addictions are common and require a multidisciplinary approach. New technologies like Virtual Reality could have the potential to improve assessment and treatment of these disorders.

Objective: In the present paper, we therefore present an overview of Virtual Reality (Head Mounted Devices) in the field of addiction medicine for craving assessment and treatment.

Method: We conducted a systematic review by querying PubMed database for the titles of articles published up to March 2019 with the terms [virtual] AND [addictive] OR [addiction] OR [substance] OR [alcohol] OR [cocaine] OR [cannabis] OR [opioid] OR [tobacco] OR [nicotine] OR [methamphetamine] OR [gaming] OR [gambling].

Results: We screened 319 abstracts and analyzed 37 articles, dividing them into two categories, the first for assessment of cue reactivity (craving, psychophysiological response and attention to cue) and the second for intervention, each drug (nicotine, cocaine, alcohol, cannabis, gambling) being detailed within each category.

Conclusions: This overview suggest that VR provide benefits in the assessment and treatment of substance use disorders and behavior addictions and achieve high levels of ecological validity. While, craving provocation in VR is effective across addiction disorders, treatments based exclusively on virtual exposure to drug related cues as shown heterogenous results.

Effect of nicotine lozenge use prior to smoking cue presentation on craving and withdrawal symptom severity

BACKGROUND

Smokers are often advised to use nicotine lozenge after cravings or withdrawal symptoms are present, which may be too late to prevent lapses. This study assesses if lozenge use prior to smoking cue exposure attenuates cue-induced increases in symptom severity.

METHODS

In this randomized, cross-over study, participants completed three laboratory sessions at which they proceeded through 4 "rooms" in a virtual reality environment. The first and last "rooms" contained neutral cues and the others contained smoking cues. At one session, a 4 mg nicotine lozenge was not given until after cue exposure (to approximate current use: i.e., after craving and withdrawal symptoms occur). At the other two sessions either a nicotine or placebo lozenge was used 15 min before cue exposure procedures. Craving and withdrawal symptoms were measured throughout each laboratory session.

RESULTS

Of 58 participants randomized; 40 completed all 3 labs. Absolute levels of craving and withdrawal symptom severity during cue exposure were lower when placebo or active lozenge was used prior to cue presentation procedures vs. no treatment until after cue presentation procedures (all p-values <0.05). There were no differences among conditions in the magnitude of symptom severity increase occurring between the first neutral room and the cue rooms.

CONCLUSIONS

Lozenge use prior to cue exposure may minimize cue induced symptom severity but when taken 15 min prior to cues the decrease is not different than placebo. Research is needed to determine if another time-frame relative to cue exposure would be more effective.

The role of virtual reality intervention on young adult smokers' motivation to quit smoking: a feasibility and pilot study

The objective of our research was to compare the initial efficacy and acceptability, in this special population, of different motivational stimuli to improve motivation to quit smoking. We enrolled 40 young adult smokers, between their twenties and their thirties, not motivated to quit. Our study adopted a visual analog scale to assess the motivation to quit at first visit (baseline) and after three different types of stimuli: a packet of cigarettes containing shocking images; a brief film showing pulmonary effects of smoking; a virtual reality period based on the progression of smoking-related illnesses. We compared the motivation to quit smoking between the series of stimuli and between the stimuli and the baseline assessment. Compared with the first assessment, all stimuli were significant in improving the motivation for smoking cessation. There was a statistically significant modification between the packet of cigarettes and the movie. The difference between the packet of cigarettes containing shocking images and the virtual reality was significant. The difference between the film and the virtual reality was also highly significant. The application of virtual reality would appear to greatly increase the motivation to smoking cessation in young adult smokers not motivated to quit.

Gamification to Motivate the Unmotivated Smoker: The "Take a Break" Digital Health Intervention

Objective: Digital health technologies most often reach only those more motivated to engage, particularly when preventive health is targeted. To test whether gamification could be used to engage low-motivation smokers, we conceptualized "Take a Break"-a 3-week technology-assisted challenge for smokers to compete in setting and achieving brief abstinence goals. Materials and Methods: In the feasibility study of the multi-technology Take a Break challenge, low-motivation smokers were given (1) daily motivational messages, (2) brief "challenge quizzes" related to smoking behaviors, (3) a telehealth call to personalize their abstinence goal for the challenge, (4) "coping minigames" to help manage cravings while attempting to achieve their brief abstinence goals, and (5) a leaderboard "webApp," providing comparative feedback on smokers' participation, and allowing for competition. Heterogeneity of engagement was tracked. Results: All 41 smokers initially reported that they were not actively quitting. Over half were employed less than full time (51%), completed less than a 4-year college education (76%), and experienced financial stress (54%). No smokers opted out of the motivational messages, and mean proportion of response to the challenge quizzes was 0.88 (SD = 0.19). Half of the smokers reported using the "coping minigames." Almost all set abstinence goals (78%), with over half lasting 1-2 days (51%); median = 1 day (IQR 1-7). Leaderboard points ranged widely. Conclusions: Rates of smoking in the developed world have declined, and those who remain smokers are complex and have lower motivation to quit. Using a game-inspired challenge, we achieved high levels of engagement from low-motivation smokers.

Attention allocation to 2D and 3D emotion-inducing scenes: A neurophysiological study

Past research on emotions was mostly supported on emotion inducing slides, but studies in the field are moving towards more ecological stimuli, including 3D stimuli and virtual reality scenes. The present study aims to compare the effects of two-dimensional (2D) and three-dimensional (3D) emotion-inducing scenes in the modulation of attention, as indexed by the amplitude of the P3 event-related component in a dual-task paradigm. We recorded the EEG signal of 31 healthy male participants performing an active auditory oddball task, while simultaneously observing pleasant, unpleasant and neutral scenes in 2D or 3D. We analyzed the effects of emotional valence and visualization mode in the mean amplitude of the P3 component at Pz. The results revealed than revealed that 2D scenarios were as effective as 3D stimuli in capturing attention resources and this effect was consistently observed in all emotional scenes.

Recommendations for Methodology of Virtual Reality Clinical Trials in Health Care by an International Working Group: Iterative Study

BACKGROUND

Therapeutic virtual reality (VR) has emerged as an efficacious treatment modality for a wide range of health conditions. However, despite encouraging outcomes from early stage research, a consensus for the best way to develop and evaluate VR treatments within a scientific framework is needed.

OBJECTIVE

We aimed to develop a methodological framework with input from an international working group in order to guide the design, implementation, analysis, interpretation, and communication of trials that develop and test VR treatments.

METHODS

A group of 21 international experts was recruited based on their contributions to the VR literature. The resulting Virtual Reality Clinical Outcomes Research Experts held iterative meetings to seek consensus on best practices for the development and testing of VR treatments.

RESULTS

The interactions were transcribed, and key themes were identified to develop a scientific framework in order to support best practices in methodology of clinical VR trials. Using the Food and Drug Administration Phase I-III pharmacotherapy model as guidance, a framework emerged to support three phases of VR clinical study designs-VR1, VR2, and VR3. VR1 studies focus on content development by working with patients and providers through the principles of human-centered design. VR2 trials conduct early testing with a focus on feasibility, acceptability, tolerability, and initial clinical efficacy. VR3 trials are randomized, controlled studies that evaluate efficacy against a control condition. Best practice recommendations for each trial were provided.

CONCLUSIONS

Patients, providers, payers, and regulators should consider this best practice framework when assessing the validity of VR treatments.

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.

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.

Crave-Out: A Distraction/Motivation Mobile Game to Assist in Smoking Cessation

Background

Smoking is still the number one preventable cause of death. Cravings—an intense desire or longing for a cigarette—are a major contributor to quit attempt failure. New tools to help smokers’ manage their cravings are needed.

Objective

To present a case study of the development process and testing of a distraction/motivation game (Crave-Out) to help manage cravings.

Methods

We used a phased approach: in Phase 1 (alpha testing), we tested and refined the game concept, using a Web-based prototype. In Phase 2 (beta testing), we evaluated the distraction/motivation potential of the mobile game prototype, using a prepost design. After varying duration of abstinence, smokers completed the Questionnaire of Smoking Urge-Brief (QSU-Brief) measurement before and after playing Crave-Out. Paired t tests were used to compare pregame and postgame QSU-Brief levels. To test dissemination potential, we released the game on the Apple iTunes App Store and tracked downloads between December 22, 2011, and May 5, 2014.

Results

Our concept refinement resulted in a multilevel, pattern memory challenge game, with each level increasing in difficulty. Smokers could play the game as long as they wanted. At the end of each level, smokers were provided clear goals for the next level and rewards (positive reinforcement using motivational tokens that represented a benefit of quitting smoking). Negative reinforcement was removed in alpha testing as smokers felt it reminded them of smoking. Measurement of QSU-Brief (N=30) resulted in a pregame mean of 3.24 (SD 1.65) and postgame mean of 2.99 (SD 1.40) with an overall decrease of 0.25 in cravings (not statistically significant). In a subset analysis, the QSU-Brief decrease was significant for smokers abstinent for more than 48 hours (N=5) with a pregame mean of 2.84 (SD 1.16) and a postgame mean of 2.0 (SD 0.94; change=0.84; P =.03). Between December 22, 2011, and May 29, 2014, the game was downloaded 3372 times from the App-Store, with 1526 smokers visiting the online resource www.decide2quit.org linked to the game.

Conclusions

Overall, playing the game resulted in small, but nonsignificant decreases in cravings, with changes greater for those had already quit for more than 48 hours. Lessons learned can inform further development. Future research could incorporate mHealth games in multicomponent cessation interventions.

Trial Registration

Clinicaltrials.gov NCT00797628; https://clinicaltrials.gov/ct2/show/NCT00797628 (Archived by WebCite at http://www.webcitation.org/6hbJr6LWG)

The Role of Cross-Cue Reactivity in Coexisting Smoking and Gambling Habits

Cigarette smoking is the most common addictive behaviour co-occurring with problem gambling. Based on classical conditioning, smoking and gambling cues may acquire conditioned stimulus properties that elicit cravings for both behaviours. This study examined cross-cue reactivity in 75 men who were regular smokers, poker players or cigarette-smoking poker players. Participants were exposed to discrete cigarette, poker and neutral cues while skin conductance and psychological urges to smoke and gamble were measured. Results showed evidence of cross-cue reactivity based on skin conductance, and subjective response to smoking cues; subjective response to gambling cues was less clear. Smoking gamblers showed greater skin conductance reactivity to cues, and stronger subjective urges to smoke to smoking and gambling cues, compared to individuals who only smoked or only gambled. This study demonstrates evidence for cross-cue reactivity between a substance and a behavioural addiction, and the results encourage further research.

The Use of Virtual Reality in the Production of Cue-Specific Craving for Cigarettes: A Meta-Analysis

INTRODUCTION

The cue-reactivity procedure has demonstrated that smokers respond with increases in subjective craving in the presence of smoking-related cues. Virtual reality is an emerging mode of cue presentation for cue-reactivity research. Despite the successful implementation of virtual reality during the last decade, no systematic review has investigated the magnitude of effects across studies.

METHODS

This research systematically reviewed findings from studies using virtual reality in cigarette craving assessment. Eligible studies assessed subjective craving for cigarettes in smokers exposed to smoking-related and neutral environments. Cohen's d was used to assess differences in craving between smoking-related and nonsmoking-related virtual environments. A random effects approach was used to combine effect sizes.

RESULTS

A total of 18 studies involving 541 smokers was included in the final analyses. Environments with smoking-related cues produced significant increases in craving relative to environments without smoking-related cues. The mean overall effect size (Cohen's d) was 1.041 (SE = 0.12, 95% CI = 0.81 to 1.28, Z = 8.68, P < .001).

CONCLUSIONS

The meta-analysis suggested that presentations of smoking cues through virtual reality can produce strong increases in craving among cigarette smokers. This strong cue-reactivity effect, which was comparable in magnitude to the craving effect sizes found with more conventional modes of cue presentation, supports the use of virtual reality for the generation of robust cue-specific craving in cue-reactivity research.

Withdrawal Symptoms and Nicotine Dependence Severity Predict Virtual Reality Craving in Cigarette-Deprived Smokers

INTRODUCTION

Virtual reality (VR) has been shown to be effective in eliciting responses to nicotine cues in cigarette smokers. The primary aim of this study was to investigate whether cigarette-deprived smokers would exhibit increased craving and changes in heart rate when viewing cigarette related cues as compared to non-smoking cues in a VR environment, and the secondary aim was to assess the extent to which self-assessed measures of withdrawal and dependence correlated with VR craving.

METHODS

Nicotine-dependent cigarette smokers were recruited for a 2 day study. On Day 1, participants smoked as usual and on Day 2 were deprived from smoking overnight. On both days, participants completed self-assessment questionnaires on withdrawal, craving, and nicotine-dependence. Participants completed a VR session during the cigarette deprivation condition only (Day 2). During this session, they were exposed to active smoking and placebo (non-smoking) cues.

RESULTS

The data show that self-reported levels of "craving" (p < .01) and "thinking about cigarettes" (p < .0001) were significantly greater after exposure to the active cues versus non-smoking cues. Significant increases in heart rate were found for 3 of 4 active cues when compared to non-smoking cues (p < .05). Finally, significant positive correlations were found between self-reported craving prior to the VR session and craving induced by active VR cues (p < .01).

CONCLUSIONS

In this report, active VR cues elicited craving during cigarette deprivation. This is the first study to demonstrate that self-reported craving, withdrawal symptoms, and nicotine dependence severity predict cue-induced craving in the VR setting.

The use of virtual reality in craving assessment and cue-exposure therapy in substance use disorders

Craving is recognized as an important diagnosis criterion for substance use disorders (SUDs) and a predictive factor of relapse. Various methods to study craving exist; however, suppressing craving to successfully promote abstinence remains an unmet clinical need in SUDs. One reason is that social and environmental contexts recalling drug and alcohol consumption in the everyday life of patients suffering from SUDs often initiate craving and provoke relapse. Current behavioral therapies for SUDs use the cue-exposure approach to suppress salience of social and environmental contexts that may induce craving. They facilitate learning and cognitive reinforcement of new behavior and entrain craving suppression in the presence of cues related to drug and alcohol consumption. Unfortunately, craving often overweighs behavioral training especially in real social and environmental contexts with peer pressure encouraging the use of substance, such as parties and bars. In this perspective, virtual reality (VR) is gaining interest in the development of cue-reactivity paradigms and practices new skills in treatment. VR enhances ecological validity of traditional craving-induction measurement. In this review, we discuss results from (1) studies using VR and alternative virtual agents in the induction of craving and (2) studies combining cue-exposure therapy with VR in the promotion of abstinence from drugs and alcohol use. They used virtual environments, displaying alcohol and drugs to SUD patients. Moreover, some environments included avatars. Hence, some studies have focused on the social interactions that are associated with drug-seeking behaviors and peer pressure. Findings indicate that VR can successfully increase craving. Studies combining cue–exposure therapy with virtual environment, however, reported mitigated success so far.

Eliciting nicotine craving with virtual smoking cues

Craving is a strong desire to consume that emerges in every case of substance addiction. Previous studies have shown that eliciting craving with an exposure cues protocol can be a useful option for the treatment of nicotine dependence. Thus, the main goal of this study was to develop a virtual platform in order to induce craving in smokers. Fifty-five undergraduate students were randomly assigned to two different virtual environments: high arousal contextual cues and low arousal contextual cues scenarios (17 smokers with low nicotine dependency were excluded). An eye-tracker system was used to evaluate attention toward these cues. Eye fixation on smoking-related cues differed between smokers and nonsmokers, indicating that smokers focused more often on smoking-related cues than nonsmokers. Self-reports of craving are in agreement with these results and suggest a significant increase in craving after exposure to smoking cues. In sum, these data support the use of virtual environments for eliciting craving.

Smoking a virtual cigarette increases craving among smokers

Previous studies have shown the efficacy of virtual reality (VR) environments that reproduce smoking-related stimuli for increasing self-reported craving and psychophysiological reactivity in smokers. However, no study to date has attempted to simulate smoking behavior itself by means of VR technology. The aim of this study was to assess the effect of smoking a virtual cigarette on self-reported craving levels and heart rate (HR) in a sample of smokers. Participants were 45 smokers randomly assigned to three VR conditions built into a virtual pub: smoking a virtual cigarette, throwing virtual darts at a virtual dartboard or just being in the virtual pub. Results showed that smoking a virtual cigarette significantly increased self-reported craving and HR when compared to the other two conditions. These results reveal that simulation of smoking behavior in a VR environment functions as an efficacious proximal cue that can be used for triggering craving under the cue-exposure paradigm.

Comparison of craving between smoked and smokeless tobacco across a variety of cue exposures

Smokeless tobacco use is a major health issue but has received less attention in craving research. The present non-funded study aimed to assess craving associated with smokeless tobacco compared to smoked forms. Forty-eight nicotine dependent male subjects attending a deaddiction center in India were recruited. The subjects were exposed to six nicotine related and two control cues in random order for variable time durations. The urge to consume the tobacco product was rated. Tobacco-related cues produced different patterns and degrees of craving among users of smoked and smokeless tobacco. This has implications for management and drug development.

Effects of D-cycloserine on cue-induced craving and cigarette smoking among concurrent cocaine- and nicotine-dependent volunteers

Rates of cigarette smoking are 3- to 4-fold greater among those with cocaine-dependence, and compared to non-users, cocaine users are at greater risk of incurring smoking-related negative health effects and death. The current study examined D-cycloserine's (0 or 50mg once weekly) effects on 1) extinction of cue-induced craving for cigarettes, 2) cigarette smoking in conjunction with cognitive-behavioral therapy, and 3) safety and tolerability in cocaine-dependent smokers. This was a double-blind, placebo-controlled, between groups, outpatient study. Participants (N=29) were concurrent cocaine- and nicotine-dependent volunteers seeking treatment for their cigarette smoking. Study visits were 3 times per week for 4 consecutive weeks. At each visit, participants received cognitive-behavioral therapy for smoking, were exposed to smoking cues. A subset of participants (N=22) returned for 6-month follow-up visits. While craving decreased, no significant effects of D-cycloserine treatment were observed. Likewise, significant decreases in smoking were observed at study days 6 (p<0.002) and 12 (p<0.0001) relative to baseline, although no participants achieved complete abstinence. However, there was no effect of D-cycloserine on cigarette smoking during treatment or at 6-mos follow-up. The treatment was safe and tolerable, with nearly 90% of treatment sessions attended based on an intent-to-treat analysis. While no effects of D-cycloserine on craving or smoking were observed in the current study, the results do suggest that smoking treatment is well accepted and may be effective for cocaine-dependent individuals.

Validation of smoking-related virtual environments for cue exposure therapy

Craving is considered one of the main factors responsible for relapse after smoking cessation. Cue exposure therapy (CET) consists of controlled and repeated exposure to drug-related stimuli in order to extinguish associated responses. The main objective of this study was to assess the validity of 7 virtual reality environments for producing craving in smokers that can be used within the CET paradigm. Forty-six smokers and 44 never-smokers were exposed to 7 complex virtual environments with smoking-related cues that reproduce typical situations in which people smoke, and to a neutral virtual environment without smoking cues. Self-reported subjective craving and psychophysiological measures were recorded during the exposure. All virtual environments with smoking-related cues were able to generate subjective craving in smokers, while no increase was observed for the neutral environment. The most sensitive psychophysiological variable to craving increases was heart rate. The findings provide evidence of the utility of virtual reality for simulating real situations capable of eliciting craving. We also discuss how CET for smoking cessation can be improved through these virtual tools.

Using virtual reality to investigate complex and contextual cue reactivity in nicotine dependent problem drinkers

Alcohol and cigarette smoking frequently co-occur among adults in the U.S., resulting in a myriad of deleterious health outcomes. Cue reactivity has been posited as one factor that precludes individuals from overcoming alcohol and nicotine dependency. While cue reactivity studies have focused on the impact of proximal cues on cue reactivity, much less is known about the unique impact of complex and contextual cues. This pilot study compares nicotine and alcohol cue reactivity among a sample of nicotine dependent, daily drinkers (N=21) across neutral, party, and office courtyard virtual reality (VR) contexts embedded with proximal smoking cues to: 1) explore and compare the effects of complex nicotine cues on alcohol cross-cue reactivity between nicotine/alcohol dependent drinkers and nicotine dependent/non-alcohol dependent daily drinkers, and 2) assess the effectiveness of VR for eliciting cue-induced nicotine craving responses using complex nicotine cues. Nicotine dependent/non-alcohol dependent drinkers had significantly lower craving for alcohol in the non-alcohol congruent office courtyard VR scene and there was no difference in the alcohol-congruent party scene when compared to the alcohol dependent group, suggesting that the non-alcohol dependent daily drinking group was more likely to react to contextual cues. Consistent with prior cue reactivity studies, dependent smokers experienced significantly higher craving for nicotine in the VR smoking congruent contexts compared to the neutral contexts; however, nicotine/alcohol dependent participants did not return to baseline craving after exposure to smoking cues. These results suggest substantive differences in the ways that nicotine-dependent, daily alcohol drinkers and nicotine/alcohol dependent drinkers experience craving, whether cross-cue or traditional.

Methamphetamine craving induced in an online virtual reality environment

The main aim of this study was to assess self-reported craving and physiological reactivity in a methamphetamine virtual reality (METH-VR) cue model created using Second Life, a freely available online gaming platform. Seventeen, non-treatment seeking, individuals that abuse methamphetamine (METH) completed this 1-day, outpatient, within-subjects study. Participants completed four test sessions: 1) METH-VR, 2) neutral-VR, 3) METH-video, and 4) neutral-video in a counterbalanced (Latin square) fashion. The participants provided subjective ratings of urges to use METH, mood, and physical state throughout each cue presentation. Measures of physiological reactivity (heart rate variability) were also collected during each cue presentation and at rest. The METH-VR condition elicited the greatest change in subjective reports of "crave METH", "desire METH", and "want METH" at all time points. The "high craving" participants displayed more high frequency cardiovascular activity while the "low craving" participants displayed more low frequency cardiovascular activity during the cue conditions, with the greatest difference seen during the METH-VR and METH-video cues. These findings reveal a physiological divergence between high and low craving METH abusers using heart rate variability, and demonstrate the usefulness of VR cues for eliciting subjective craving in METH abusers, as well as the effectiveness of a novel VR drug cue model created within an online virtual world.

Crushing virtual cigarettes reduces tobacco addiction and treatment discontinuation

Pilot studies revealed promising results regarding crushing virtual cigarettes to reduce tobacco addiction. In this study, 91 regular smokers were randomly assigned to two treatment conditions that differ only by the action performed in the virtual environment: crushing virtual cigarettes or grasping virtual balls. All participants also received minimal psychosocial support from nurses during each of 12 visits to the clinic. An affordable virtual reality system was used (eMagin HMD) with a virtual environment created by modifying a 3D game. Results revealed that crushing virtual cigarettes during 4 weekly sessions led to a statistically significant reduction in nicotine addiction (assessed with the Fagerström test), abstinence rate (confirmed with exhaled carbon monoxide), and drop-out rate from the 12-week psychosocial minimal-support treatment program. Increased retention in the program is discussed as a potential explanation for treatment success, and hypotheses are raised about self-efficacy, motivation, and learning.

Influence of smoking cues in movies on craving among smokers

AIMS

Research has shown that smoking-related cues are important triggers for craving. The objective of the present study was to test whether smoking cues in movies also function as triggers to evoke craving. To accomplish this, we conducted a pilot study in which we examined smokers' reactivity to smoking cues from a particular movie in a common cue-reactivity paradigm using pictures. In the main study, we tested whether smokers who are confronted with smoking characters in a movie segment have a greater desire to smoke than smokers confronted with non-smoking characters.

DESIGN

Using an experimental design, participants were assigned randomly to one of two movie conditions (smoking versus non-smoking characters).

SETTING

In a laboratory, that reflected a naturalistic setting, participants watched a 41-minute movie segment.

PARTICIPANTS

A total of 65 young adults who smoked on a daily basis participated in the experiment.

MEASUREMENTS

Craving was assessed before and after watching the movie.

FINDINGS

The pilot study revealed that pictures of smoking characters had strong effects on craving. However, when smokers actually watched a movie segment, no differences in craving were found between those who watched smoking characters and those who watched non-smoking characters. This finding was not affected by baseline craving, the time of the last cigarette smoked and daily smoking habits.

CONCLUSIONS

No effect of smoking cues in movies on craving was found, in contrast with research supporting the cue-craving link. Thus, if replicated, this might indicate that smoking cues in such contexts do not affect smokers' desire to smoke as expected.

Development of a Virtual Reality Coping Skills Game to Prevent Post-Hospitalization Smoking Relapse in Tobacco Dependent Cancer Patients

Many hospitalized smokers return to smoking after hospital discharge even though continued smoking can compromise treatment effectiveness, reduce survival, increase risk of disease recurrence, and impair quality of life. After leaving a smoke-free hospital, patients encounter smoking cues at home, such as family members who smoke or emotional triggers such as stress, which can elicit powerful urges to smoke and lead to smoking relapse. Enabling smokers to experience such urges in a controlled setting while providing the ability to practice coping skills may be a useful strategy for building quitting self-efficacy. We are developing a virtual reality coping skills (VRCS) game to help hospitalized smokers practice coping strategies to manage these triggers in preparation for returning home after hospitalization. Our multidisciplinary team developed a prototype VRCS game using Second Life, a platform that allowed rapid construction of a virtual reality environment. The prototype contains virtual home spaces (e.g., living room, kitchen) populated with common triggers to smoke and a "toolkit" with scripted actions that enable the avatar to rehearse various coping strategies. Since eliciting and managing urges to smoke is essential to the game's utility as an intervention, we assessed the ability of the prototype virtual environment to engage former smokers in these scenarios. We recruited eight former smokers with a recent history of hospitalization and guided each through a VRCS scenario during which we asked the patient to evaluate the strength of smoking urges and usefulness of coping strategies. Initial data indicate that patients report high urges to smoke (mean = 8.8 on a 10 point scale) when their avatar confronted virtual triggers such as drinking coffee. Patients rated virtual practice of coping strategies, such as drinking water or watching TV, as very helpful (mean = 8.4 on a 10 point scale) in reducing these urges. With further development, this VRCS game may have potential to provide low-cost, effective behavioral rehearsal to prevent relapse to smoking in hospitalized patients.