Causal Interactive Links Between Presence and Fear in Virtual Reality Height Exposure

Elemental and configural representation of a conditioned context

A context can be conceptualized as a stable arrangement of elements or as the sum of single elements. Both configural and elemental representations play a role in associative processes. This study aimed to explore the respective contributions of these two representations of a context in the acquisition of conditioned anxiety in humans. Virtual reality (VR) can be an ecologically valid tool to investigate context-related mechanisms, yet the influence of the sense of presence within the virtual environment remains unclear. Forty-eight healthy individuals participated in a VR-based context conditioning wherein electric shocks (unconditioned stimulus, US) were unpredictably delivered in one virtual office (CTX+), but not in the other (CTX-). During the test phase, nine elements from each context were presented singularly. We found a cluster of participants, who exhibited heightened anticipation of the US for anxiety-related elements as compared to the other group. In contrast to their clear elemental representation, these individuals showed diminished discriminative responses between the two context's configurations. Discriminative responses to the contexts were boosted in those individuals, who had a weaker elemental representation. Importantly, the individual sense of presence significantly influenced the conditioned responses. These findings align with the dual-representation view of context and provide insights into the role of presence in eliciting (conditioned) anxiety responses.

IAVRS-International Affective Virtual Reality System: Psychometric Assessment of 360° Images by Using Psychophysiological Data

Virtual Reality is an effective technique for eliciting emotions. It provides immersive and ecologically valid emotional experiences while maintaining experimental control. Recently, novel VR forms like 360° videos have been used successfully for emotion elicitation. Some preliminary databases of 360° videos for emotion elicitation have been proposed, but they tapped mainly into an emotional dimensional approach and did not include a concurrent physiological assessment of an emotional profile. This study expands on these databases by combining dimensional and discrete approaches to validate a new set of 360° emotion-inducing images. Twenty-six participants viewed 46 immersive images, and their emotional reactions were measured using self-reporting, psychophysiological signals, and eye tracking. The IAVRS database can successfully elicit a wide range of emotional responses, including both positive and negative valence, as well as different levels of arousal. Results reveal an important correspondence between the discrete and dimensional models of emotions. Furthermore, the images that exhibit convergence between the dimensional and discrete emotional models are particularly impactful regarding arousal and valence values. The IAVRS database provides insights into potential relationships between physiological parameters and emotional responses. This preliminary investigation highlights the complexity of emotional elicitation processes and their physiological correlates, suggesting the need for further research to deepen our understanding.

The presence of fear: How subjective fear, not physiological changes, shapes the experience of presence

When we become engrossed in novels, films, games, or even our own wandering thoughts, we can feel present in a reality distinct from the real world. Although this subjective sense of presence is, presumably, a ubiquitous aspect of conscious experience, the mechanisms that produce it are unknown. Correlational studies conducted in virtual reality have shown that we feel more present when we are afraid, motivating claims that physiological changes contribute to presence; however, such causal claims remain to be evaluated. Here, we report two experiments that test the causal role of subjective and physiological components of fear (i.e., activation of the sympathetic nervous system) in generating presence. In Study 1, we validated a virtual reality simulation capable of inducing fear. Participants rated their emotions while they crossed a wooden plank that appeared to be suspended above a city street; at the same time, we recorded heart rate and skin conductance levels. Height exposure increased ratings of fear, presence, and both measures of sympathetic activation. Although presence and fear ratings were correlated during height exposure, presence and sympathetic activation were unrelated. In Study 2, we manipulated whether the plank appeared at height or at ground level. We also captured participants' movements, which revealed that alongside increases in subjective fear, presence, and sympathetic activation, participants also moved more slowly at height relative to controls. Using a mediational approach, we found that the relationship between height exposure and presence on the plank was fully mediated by self-reported fear, and not by sympathetic activation. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Emotion in motion: perceiving fear in the behaviour of individuals from minimal motion capture displays

The ability to quickly and accurately recognise emotional states is adaptive for numerous social functions. Although body movements are a potentially crucial cue for inferring emotions, few studies have studied the perception of body movements made in naturalistic emotional states. The current research focuses on the use of body movement information in the perception of fear expressed by targets in a virtual heights paradigm. Across three studies, participants made judgments about the emotional states of others based on motion-capture body movement recordings of those individuals actively engaged in walking a virtual plank at ground-level or 80 stories above a city street. Results indicated that participants were reliably able to differentiate between height and non-height conditions (Studies 1 & 2), were more likely to spontaneously describe target behaviour in the height condition as fearful (Study 2) and their fear estimates were highly calibrated with the fear ratings from the targets (Studies 1-3). Findings show that VR height scenarios can induce fearful behaviour and that people can perceive fear in minimal representations of body movement.

Effects of cannabidiol on psychosocial stress, situational anxiety and nausea in a virtual reality environment: a protocol for a single-centre randomised clinical trial

INTRODUCTION

The non-intoxicating plant-derived cannabinoid, cannabidiol (CBD), has demonstrated therapeutic potential in a number of clinical conditions. Most successful clinical trials have used relatively high (≥300 mg) oral doses of CBD. Relatively few studies have investigated the efficacy of lower (<300 mg) oral doses, typical of those available in over-the-counter CBD products.

METHODS

We present a protocol for a randomised, double-blind, placebo-controlled, parallel-group clinical trial investigating the effects of a low oral dose (150 mg) of CBD on acute psychosocial stress, situational anxiety, motion sickness and cybersickness in healthy individuals. Participants (n=74) will receive 150 mg of CBD or a matched placebo 90 min before completing three virtual reality (VR) challenges (tasks) designed to induce transient stress and motion sickness: (a) a 15 min 'Public Speaking' task; (b) a 5 min 'Walk the Plank' task (above a sheer drop); and (c) a 5 min 'Rollercoaster Ride' task. The primary outcomes will be self-reported stress and nausea measured on 100 mm Visual Analogue Scales. Secondary outcomes will include salivary cortisol concentrations, skin conductance, heart rate and vomiting episodes (if any). Statistical analyses will test the hypothesis that CBD reduces nausea and attenuates subjective, endocrine and physiological responses to stress compared with placebo. This study will indicate whether low-dose oral CBD has positive effects in reducing acute psychosocial stress, situational anxiety, motion sickness and cybersickness.

ETHICS AND DISSEMINATION

The University of Sydney Human Research Ethics Committee has granted approval (2023/307, version 1.6, 16 February 2024). Study findings will be disseminated in a peer-reviewed journal and at academic conferences.

TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry (ACTRN12623000872639).

Virtual reality exposure with vibrotactile stimulation for the treatment of fear of flying: A pilot study

BACKGROUND AND OBJECTIVES

Virtual reality (VR) interventions are becoming more prevalent in treating fear of flying (FoF). Since multisensory stimulation can enhance the sense of presence in a virtual environment, the present study compared virtual reality exposure with and without vibrotactile cues to determine its contribution to the realism of the virtual experience.

METHODS

A repeated measures design was used. Thirty-one participants were exposed to two experimental conditions with a minimum of a one-week interval between them: one in which participants were exposed to the virtual environment with vibrotactile cues (smart chair, SC), and another in which participants were exposed to the virtual environment without vibrotactile cues (ordinary chair, OC). The administration order of both conditions was counterbalanced to avoid possible order effects.

RESULTS

Participants felt higher levels of sense of presence when using the SC than the OC. However, the addition of vibrotactile stimulation partially influenced experienced anxiety. Some personality traits were also associated with participants' sense of presence and anxiety responses during the exposure.

LIMITATIONS

The sample size was smaller than required. Moreover, only self-reported measures were used. Finally, a roller coaster instead of an airplane scenario was used for the exposure, which might not have been suitable enough for provoking anxiety in participants with FoF.

CONCLUSIONS

Vibrotactile cues enhanced the sense of presence. However, the addition of vibrotactile stimulation did not have a consistent effect on anxiety experienced during exposure. Therefore, the benefits of incorporating vibrotactile cues in virtual reality environments for exposure therapy are not clear.

Reliability of repeated exposure to the human elevated plus-maze in virtual reality: Behavioral, emotional, and autonomic responses

Approach-avoidance conflicts are a hallmark of anxiety-related behaviors. A gold standard for assessing anxiety-related behaviors in rodents is the elevated plus-maze (EPM), which was recently translated to humans using immersive virtual reality. Repeated behavioral testing is particularly interesting for clinical and pharmacological research in humans but could be limited by habituation effects. Here, we tested whether comparable strategies that are used in rodents (different environments and inter-trial interval of 28 days) are sufficient to avoid habituation or sensitization effects on the EPM, making it possible to perform repeated measurement of anxiety-related behavior in humans. Moreover, we developed two novel virtual environments for repeated testing to explore whether a scenario resembling the real world is superior to a video game-like EPM in terms of lifelike physiological, emotional, and behavioral responses. On a behavioral level, no significant differences but a high correlation between first and repeated exposure to the human EPM independent of EPM version were found. On a psychophysiological level, salivary alpha-amylase, skin-conductance, and respiratory frequency increased at first and second exposure independent of EPM version. However, at repeated exposure, skin-conductance and heart rate showed indicators for anticipatory anxiety and a small sensitization effect, while no effect of real-world resemblance on these physiological measures was found. This was also reflected in slightly higher subjective anxiety levels at second exposure, although subjective anxiety still correlated strongly between first and second exposure. In conclusion, the human EPM can be used for longitudinal assessments of human anxiety-related behavior when strategies to avoid habituation and sensitization are considered.

The Effects of Virtual and Physical Elevation on Physiological Stress During Virtual Reality Height Exposure

Advances in virtual reality technology have greatly benefited the acrophobia research field. Virtual reality height exposure is a reliable method of inducing stress with low variance across ages and demographics. When creating a virtual height exposure environment, researchers have often used haptic feedback elements to improve the sense of realism of a virtual environment. While the quality of the rendered for the virtual environment increases over time, the physical environment is often simplified to a conservative passive haptic feedback platform. The impact of the increasing disparity between the virtual and physical environment on the induced stress levels is unclear. This article presents an experiment that explored the effect of combining an elevated physical platform with different levels of virtual heights to induce stress. Eighteen participants experienced four different conditions of varying physical and virtual heights. The measurements included gait parameters, heart rate, heart rate variability, and electrodermal activity. The results show that the added physical elevation at a low virtual height shifts the participant's walking behaviour and increases the perception of danger. However, the virtual environment still plays an essential role in manipulating height exposure and inducing physiological stress. Another finding is that a person's behaviour always corresponds to the more significant perceived threat, whether from the physical or virtual environment.

Presence and simulator sickness predict the usability of a virtual reality attention task

Attention is the ability to actively process specific information within one's environment over longer periods of time while disregarding other details. Attention is an important process that contributes to overall cognitive performance from performing every day basic tasks to complex work activities. The use of virtual reality (VR) allows study of the attention processes in realistic environments using ecological tasks. To date, research has focused on the efficacy of VR attention tasks in detecting attention impairment, while the impact of the combination of variables such as mental workload, presence and simulator sickness on both self-reported usability and objective attention task performance in immersive VR has not been examined. The current study tested 87 participants on an attention task in a virtual aquarium using a cross-sectional design. The VR task followed the continuous performance test paradigm where participants had to respond to correct targets and ignore non-targets over 18 min. Performance was measured using three outcomes: omission (failing to respond to correct targets), commission errors (incorrect responses to targets) and reaction time to correct targets. Measures of self-reported usability, mental workload, presence and simulator sickness were collected. The results showed that only presence and simulator sickness had a significant impact on usability. For performance outcomes, simulator sickness was significantly and weakly associated with omission errors, but not with reaction time and commission errors. Mental workload and presence did not significantly predict performance. Our results suggest that usability is more likely to be negatively impacted by simulator sickness and lack of presence than performance and that usability and attention performance are linked. They highlight the importance of considering factors such as presence and simulator sickness in attention tasks as these variables can impact usability.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10055-023-00782-3.

The reality of virtual reality

Virtual reality (VR) has become a popular tool for investigating human behavior and brain functions. Nevertheless, it is unclear whether VR constitutes an actual form of reality or is more like an advanced simulation. Determining the nature of VR has been mostly achieved by self-reported presence measurements, defined as the feeling of being submerged in the experience. However, subjective measurements might be prone to bias and, most importantly, do not allow for a comparison with real-life experiences. Here, we show that real-life and VR height exposures using 3D-360° videos are mostly indistinguishable on a psychophysiological level (EEG and HRV), while both differ from a conventional 2D laboratory setting. Using a fire truck, three groups of participants experienced a real-life (N = 25), a virtual (N = 24), or a 2D laboratory (N = 25) height exposure. Behavioral and psychophysiological results suggest that identical exogenous and endogenous cognitive as well as emotional mechanisms are deployed to process the real-life and virtual experience. Specifically, alpha- and theta-band oscillations in line with heart rate variability, indexing vigilance, and anxiety were barely indistinguishable between those two conditions, while they differed significantly from the laboratory setup. Sensory processing, as reflected by beta-band oscillations, exhibits a different pattern for all conditions, indicating further room for improving VR on a haptic level. In conclusion, the study shows that contemporary photorealistic VR setups are technologically capable of mimicking reality, thus paving the way for the investigation of real-world cognitive and emotional processes under controlled laboratory conditions. For a video summary, see https://youtu.be/fPIrIajpfiA.

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.

A Survey on Affective and Cognitive VR

In Virtual Reality (VR), users can be immersed in emotionally intense and cognitively engaging experiences. Yet, despite strong interest from scholars and a large amount of work associating VR and Affective and Cognitive States (ACS), there is a clear lack of structured and systematic form in which this research can be classified. We define "Affective and Cognitive VR" to relate to works which (1) induce ACS, (2) recognize ACS, or (3) exploit ACS by adapting virtual environments based on ACS measures. This survey clarifies the different models of ACS, presents the methods for measuring them with their respective advantages and drawbacks in VR, and showcases Affective and Cognitive VR studies done in an Immersive Virtual Environment (IVE) in a non-clinical context. Our article covers the main research lines in Affective and Cognitive VR. We provide a comprehensive list of references with the analysis of 63 research articles and summarize future works directions.

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.

Biomarkers of Anxiety Acquisition and Generalization in Virtual Reality Experiments

Abstract. Anxiety disorders are characterized by exaggerated responses to a threatening situation and overgeneralization. Context conditioning has been used for the identification of risk factors. This systematic literature search identifies 16 articles published between 1990 and 2021 on differential anxiety conditioning and generalization in humans. Additionally, we provide example data for individuals suffering from panic attacks with and without depressive symptoms. Successful anxiety acquisition (discrimination between anxiety and safety context) was found on the subjective level of anxiety and US-expectancy, on the physiological level of electrodermal activity, and in the defensive behavior of startle response. Anxiety generalization (discrimination between generalization and safety context) was found on the verbal but not on the physiobehavioral level. In sum, we emphasize the impact of virtual reality on anxiety research. Verbal and physiobehavioral responses serve as reliable biomarkers for anxiety. Few studies found ratings to be the best predictor for anxiety generalization. Genetic predisposition or personality traits might foster overgeneralization.

Characterizing Physiological Responses to Fear, Frustration, and Insight in Virtual Reality

Physiological sensing often complements studies of human behavior in virtual reality (VR) to detect users' affective and cognitive states. Some psychological states, such as fear and frustration, can be particularly hard to differentiate from a physiological perspective as they are close in the arousal and valence emotional space. Moreover, it is largely unclear how users' physiological reactions are expressed in response to transient psychological states such as fear, frustration, and insight-especially since these are rich indicators for characterizing users' responses to dynamic systems but are hard to capture in highly interactive settings. We conducted a study ($N=24$) to analyze participants' pulmonary, electrodermal, cardiac, and pupillary responses to moments of fear, frustration, and insight in immersive settings. Participants interacted in five VR environments, throughout which we measured their physiological reactions and analyzed the patterns we observed. We also measured subjective fear and frustration using questionnaires. We found differences between fear and frustration pupillary, respiratory, and electrodermal responses, as well as between the pupillary changes that followed fear in a horror game and those that followed fear in a vertigo experiment. We present the relationships between fear levels, frustration levels, and their physiological responses. To detect these affective events and states, we introduce user-independent binary classification models that achieved an average micro $F_{1}$ score of 71% for detecting fear in a horror game, 75% for fear of vertigo, 76% for frustration, and 75% for insight, showing the promise for detecting these states from passive and objective signals.

Evoking stress reactivity in virtual reality: A systematic review and meta-analysis

BACKGROUND

Virtual reality (VR) research probes stress environments that are infeasible to create in the real world. However, because research simulations are applied to narrow populations, it remains unclear if VR simulations can stimulate a broadly applicable stress-response. This systematic review and meta-analysis was conducted on studies using VR stress tasks and biomarkers.

METHODS

Included papers (N = 52) measured cortisol, heart rate (HR), galvanic skin response (GSR), systolic blood pressure (SBP), diastolic blood pressure (DBP), respiratory sinus arrhythmia (RSA), parasympathetic activity (RMSSD), sympathovagal balance (LF/HF), and/or salivary alpha-amylase (sAA). Effect sizes (ES) and confidence intervals (CI) were calculated based on standardized mean change of baseline-to-peak biomarker levels.

RESULTS

From baseline-to-peak (ES, CI), analyses showed a statistically significant change in cortisol (0.56, 0.28-0.83), HR (0.68, 0.53-0.82), GSR (0.59, 0.36-0.82), SBP (.55, 0.19-0.90), DBP (.64, 0.23-1.05), RSA (-0.59, -0.88 to -0.30), and sAA (0.27, 0.092-0.45). There was no effect for RMSSD and LF/HF.

CONCLUSION

VR stress tasks elicited a varied magnitude of physiological stress reactivity. VR may be an effective tool in stress research.

Immersive media experience: a survey of existing methods and tools for human influential factors assessment

Virtual reality (VR) applications, especially those where the user is untethered to a computer, are becoming more prevalent as new hardware is developed, computational power and artificial intelligence algorithms are available, and wireless communication networks are becoming more reliable, fast, and providing higher reliability. In fact, recent projections show that by 2022 the number of VR users will double, suggesting the sector was not negatively affected by the worldwide COVID-19 pandemic. The success of any immersive communication system is heavily dependent on the user experience it delivers, thus now more than ever has it become crucial to develop reliable models of immersive media experience (IMEx). In this paper, we survey the literature for existing methods and tools to assess human influential factors (HIFs) related to IMEx. In particular, subjective, behavioural, and psycho-physiological methods are covered. We describe tools available to monitor these HIFs, including the user's sense of presence and immersion, cybersickness, and mental/affective states, as well as their role in overall experience. Special focus is placed on psycho-physiological methods, as it was found that such in-depth evaluation was lacking from the existing literature. We conclude by touching on emerging applications involving multiple-sensorial immersive media and provide suggestions for future research directions to fill existing gaps. It is hoped that this survey will be useful for researchers interested in building new immersive (adaptive) applications that maximize user experience.

Mobile internet-based mixed-reality interactive telecollaboration system for neurosurgical procedures: technical feasibility and clinical implementation

OBJECTIVE

To increase access to health interventions and healthcare services for patients in resource-constrained settings, strategies such as telemedicine must be implemented for the allocation of medical resources across geographic boundaries. Telecollaboration is the dominant form of surgical telemedicine. In this study, the authors report and evaluate a novel mobile internet-based mixed-reality interactive telecollaboration (MIMIT) system as a new paradigm for telemedicine and validate its clinical feasibility.

METHODS

The application of this system was demonstrated for long-distance, real-time collaboration of neuroendoscopic procedures. The system consists of a local video processing workstation, a head-mounted mixed-reality display device, and a mobile remote device, connected over mobile internet (4G or 5G), allowing global point-to-point communication. Using this system, 20 cases of neuroendoscopic surgery were performed and evaluated. The system setup, composite video latency, technical feasibility, clinical implementation, and future potential business model were analyzed and evaluated.

RESULTS

The MIMIT system allows two surgeons to perform complex visual and verbal communication during the operation. The average video delay time is 184.25 msec (range 160–230 msec) with 4G mobile internet, and 23.25 msec (range 20–26 msec) with 5G mobile internet. Excellent image resolution enabled remote neurosurgeons to visualize all critical anatomical structures intraoperatively. Remote instructors could easily make marks on the surgical view; then the composite image, as well as the audio conversation, was transferred to the local surgeon. In this way, a real-time, long-distance collaboration can occur. This system was used for 20 neuroendoscopic surgeries in various cities in China and even across countries (Boston, Massachusetts, to Jingzhou, China). Its simplicity and practicality have been recognized by both parties, and there were no technically related complications recorded.

CONCLUSIONS

The MIMIT system allows for real-time, long-distance telecollaborative neuroendoscopic procedures and surgical training through a commercially available and inexpensive system. It enables remote experts to implement real-time, long-distance intraoperative interaction to guide inexperienced local surgeons, thus integrating the best medical resources and possibly promoting both diagnosis and treatment. Moreover, it can popularize and improve neurosurgical endoscopy technology in more hospitals to benefit more patients, as well as more neurosurgeons.

An internet-based treatment for flying phobia using 360° images: A feasibility pilot study

BACKGROUND

More research is needed in the field of Internet-delivered Cognitive Behavioral Treatments (ICBTs) for specific phobia in order to understand which characteristics are important in online exposure scenarios. The aim of the present work was to conduct a feasibility pilot study to explore participants' opinions, preferences, and acceptability ratings of two types of images (still images vs 360° navigable images) in an ICBT for Flying Phobia (FP). A secondary aim was to test the potential effectiveness of the two active treatment arms compared to a waiting list control group. An exploratory aim was to compare the role of navigable images vs. still images in the level of sense of presence and reality judgment and explore their possible mediation in treatment effectiveness.

METHODS

Participants were randomly allocated to three conditions: NO-FEAR Airlines with still images (n = 26), NO-FEAR Airlines with still and navigable images (n = 26), and a waiting list group (n = 26). Primary outcome measures were participants' opinions, preferences, satisfaction, and acceptance regarding the images used in the exposure scenarios. Secondary outcome measures included FP symptomatology outcomes and measures of sense of presence and reality judgment.

RESULTS

Participants in the study preferred navigable images over still images before and after treatment (over 84%), and they considered them more effective and logical for the treatment of their problem. However, adherence in the experimental conditions was low (42.3% dropout rate), and more participants withdrew from the group that included navigable images compared to the group that only included still images (14 vs. 8), with no statistical differences in attrition between the two conditions. NO-FEAR Airlines proved to be effective in reducing FP symptomatology compared to the control group, with large between-group effect sizes on all FP measures (ranging from 0.76 to 2.79). No significant mediation effect was found for sense of presence or reality judgment in treatment effectiveness.

DISCUSSION

The results of the current study suggest that participants prefer more immersive images in exposure scenarios, providing data that can help to design useful exposure scenarios to treat specific phobias in the future. They also provide evidence supporting the effectiveness of an ICBT for FP.

TRIAL REGISTRATION

Registered at Clinicaltrials.gov (NCT03900559) on April 9, 2019. Retrospectively registered.

Virtual Reality for the Treatment of Anxiety Disorders: A Scoping Review

IMPORTANCE

Virtual reality in head-mounted displays (HMD-VR) may be a valuable tool in occupational therapy to address anxiety. Findings from the virtual reality exposure therapy (VRET) literature may facilitate translation of HMD-VR to occupational therapy psychosocial practice.

OBJECTIVE

To explore how HMD-VR has been used to treat anxiety through VRET and could be translated to occupational therapy.

DATA SOURCES

We searched seven electronic databases for articles published between 2000 and 2020: CINAHL, Cochrane Library, Embase, ERIC, Ovid MEDLINE, PsycINFO, and Web of Science. Search terms included HMD-VR constructs, products, and therapy concepts. Study Selection and Data Collection: We used Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to report studies implementing VRET to treat anxiety. At least two reviewers assessed each citation, and a third resolved disagreements. Articles were included if they were in English, reported experimental data, and used HMD-VR. Letters, commentaries, book chapters, technical descriptions, theoretical papers, conference proceedings (≤4 pages), and reviews were excluded.

FINDINGS

Twenty-eight studies used HMD-VR to treat posttraumatic stress disorder (n = 3), specific phobias (n = 19), and performance-based social anxiety (n = 6); protocols and levels of evidence varied (randomized controlled trials, n = 11; controlled trials without randomization, n = 6; case-control or cohort studies, n = 11). Qualitative examination indicates HMD-VR is an effective treatment tool.

CONCLUSIONS AND RELEVANCE

HMD-VR can be a valuable tool for occupational therapy to simulate environments where clients with anxiety disorders participate. Eliciting presence through multisensory features and body representation may enhance outcomes. What This Article Adds: Drawing from the VRET literature, this scoping review suggests that HMD-VR can be used by occupational therapy practitioners to simulate ecologically valid environments, evaluate client responses to fearful stimuli, and remediate anxiety though immersion in virtual tasks when participation in natural contexts is unfeasible. Having ecologically valid environments is particularly important for people with anxiety disorders because they need support to cope when they encounter triggers in everyday life environments.

Virtual reality experiences promote autobiographical retrieval mechanisms: Electrophysiological correlates of laboratory and virtual experiences

Recent advancements in memory research indicate that virtual reality (VR) experiences are more vividly memorized as compared to conventional laboratory events. In contrast to the latter, VR experiences are highly immersive, simulating the multimodality, vividness and inclusiveness of real-life experiences. Therefore, VR might enable researchers to identify memory processes underlying events which participants have actually experienced, in contrast to conventional on-screen experiences. To differentiate the electrophysiological correlates of memory processes underlying VR experiences as compared to conventional laboratory experiences, participants watched videos either in a PC condition or in a VR condition, followed by an unannounced recognition memory test. As hypothesized, we replicated the well-established theta old/new effect for the PC condition, but remarkably, this effect was absent in the VR condition. Additionally, the latter was accompanied by significantly lower alpha activity as compared to the PC condition. As increases in theta-band responses are related to top-down control on, and memory load during retrieval, the observed theta responses might rather relate to retrieval effort than to retrieval success per se. Congruently, higher alpha activity measured over occipital sensor areas in the PC condition reflect visually guided search processes within episodic memory. The VR condition comes in with lower alpha activity, reflecting immediate and effortless memory access. Hence, our findings indicate that the retrieval of VR experiences promotes autobiographical  retrieval mechanisms, whereas recalling conventional laboratory events comes in with higher effort, which might not reflect the mechanisms of everyday memory.

360° Video virtual reality exposure therapy for public speaking anxiety: A randomized controlled trial

Public speaking anxiety (PSA) is a prevalent condition which is highly interrelated with social anxiety. PSA can be effectively treated with exposure therapy. Virtual reality exposure therapy (VRET) is increasingly being explored as a novel and cost-effective mode of treatment. No previous randomized controlled trial has examined whether stand-alone 360° video VRET is an effective intervention for treating PSA and interrelated disorder relevant fears. Further, studies have not explored whether 360° video content influences VRET outcomes. Participants with high PSA (n = 51) were randomly allocated to: 360° video VRET incorporating stimuli of audiences (360°Audience) (n = 17), 360° video VRET incorporating stimuli of empty rooms (360°Empty) (n = 16) and no treatment control (n = 18). Outcomes were measured over five time-points. Mixed ANOVA revealed a significant interaction between time and intervention group for PSA, social anxiety and fear of negative evaluation (FNE). Within-group analysis demonstrated there was a significant pre-intervention to post-intervention reduction across measures for both 360° video VRET groups: PSA 360°Audience (η_p² = .90, p<.001), 360°Empty (η_p² = .71, p < .001); social anxiety 360°Audience (η_p² = .49, p=.002), 360°Empty (η_p² = .39, p = .009); FNE 360°Audience (η_p² = .59, p<.001), 360°Empty (η_p² = .43, p = .006). Active intervention participants showed significant improvement from pre-intervention to 10-week follow-up on all measures. Findings illustrate that 360° video VRET is an efficacious way to significantly reduce PSA, social anxiety and FNE.

Embodiment in Virtual Reality Intensifies Emotional Responses to Virtual Stimuli

Modulating emotional responses to virtual stimuli is a fundamental goal of many immersive interactive applications. In this study, we leverage the illusion of illusory embodiment and show that owning a virtual body provides means to modulate emotional responses. In a single-factor repeated-measures experiment, we manipulated the degree of illusory embodiment and assessed the emotional responses to virtual stimuli. We presented emotional stimuli in the same environment as the virtual body. Participants experienced higher arousal, dominance, and more intense valence in the high embodiment condition compared to the low embodiment condition. The illusion of embodiment thus intensifies the emotional processing of the virtual environment. This result suggests that artificial bodies can increase the effectiveness of immersive applications psychotherapy, entertainment, computer-mediated social interactions, or health applications.

Promises and challenges of human computational ethology

The movements an organism makes provide insights into its internal states and motives. This principle is the foundation of the new field of computational ethology, which links rich automatic measurements of natural behaviors to motivational states and neural activity. Computational ethology has proven transformative for animal behavioral neuroscience. This success raises the question of whether rich automatic measurements of behavior can similarly drive progress in human neuroscience and psychology. New technologies for capturing and analyzing complex behaviors in real and virtual environments enable us to probe the human brain during naturalistic dynamic interactions with the environment that so far were beyond experimental investigation. Inspired by nonhuman computational ethology, we explore how these new tools can be used to test important questions in human neuroscience. We argue that application of this methodology will help human neuroscience and psychology extend limited behavioral measurements such as reaction time and accuracy, permit novel insights into how the human brain produces behavior, and ultimately reduce the growing measurement gap between human and animal neuroscience.

Addressing virtual reality misclassification: A hardware-based qualification matrix for virtual reality technology

Through its unique sensory synchronized design, virtual reality (VR) provides a convincing, user-centred experience of highly controllable scenarios. Importantly, VR is a promising modality for healthcare, where treatment efficacy has been recognized for a range of conditions. It is equally valuable across wider research disciplines. However, there is a lack of suitable criteria and consistent terminology with which to define VR technology. A considerable number of studies have misclassified VR hardware (e.g. defining laptops as VR), hindering validity and research comparisons. This review addresses these limitations and establishes a standardized VR qualification framework. As a result of a comprehensive theoretical and literature review, the hardware-based VR qualification matrix is proposed. The matrix criteria consist of (1) three-dimensional (3D) synchronized sensory stimulation; (2) degrees of freedom tracking; and (3) visual suppression of physical stimuli. To validate the model and quantify the current scale/diversity of VR misclassification, a 2019 sectional review of health-related studies was conducted. Of the 115 studies examined against standardized criteria, 35.7% utilized VR, 31.3% misclassified VR, 18.3% were considered quasi-VR, and 14.8% omitted critical specifications. The proposed model demonstrates good validity and reliability for qualifying and classifying VR. Key Practitioner Messages Virtual reality (VR) therapy has gained rapid empirical support, although many practitioners do not understand the difference between genuine and less-realistic VR variations. That has resulted from an evident lack of suitable criteria to define VR across a range of studies and protocols. Our proposed hardware-based virtual reality qualification matrix addresses issues to do with misclassification, via the introduction of standardised criteria. Applying the matrix to existing literature has revealed that more than 30% of VR studies use hardware that does not fit the high standards of rigour required for immersion in a simulated space. The model is a practical tool researchers and practitioners can use to quality and verify VR standards across research studies.

Memory for a virtual reality experience in children and adults according to image quality, emotion, and sense of presence

Numerous studies have explored the effects of virtual reality (VR) on adults' cognition. Little is known, however, of these effects in children. The aim of this study was to explore, in both children and adults, the respective roles of the specific factors of VR, such as immersion, sense of presence and emotion, on memory performance. To do so, we used a head-mounted display to present a VR experience in which we manipulated immersion by varying 3D asset quality (High and Low) and emotion by presenting negative, neutral and positive stimuli. 48 adults (M _age = 20.65) and 40 children (M _age = 11.63) were both divided into two experimental groups (High vs. Low 3D model quality). Valence, arousal, and sense of presence were self-assessed by means of questionnaires, while memory of the presented stimuli was assessed using a free recall task. We also performed physiological measurements to provide objective support for our data. Results showed that memory performance was better for emotional than for neutral stimuli regardless of age group, even though children seemed to avoid looking at negative stimuli compared to neutral ones. Memory was predicted by arousal and presence in adults and only by arousal in children. Memory was not impaired by using poor image quality when highly arousing content was displayed. This study revealed that, contrary to adults, the use of poor image quality did not protect children from strong emotional experiences in VR. The roles of familiarity and arousal are discussed to help explain these results.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10055-021-00537-y.

Virtual Reality Self-help Treatment for Aviophobia: Protocol for a Randomized Controlled Trial

BACKGROUND

Aviophobia (the fear of flying) can greatly impact the daily life functioning of people with the condition. Traditional exposure-based treatment is hampered by the limited availability of airplane practice situations, which is a result of economical and practical concerns. Easily accessible and low-cost virtual reality exposure therapy may address these challenges.

OBJECTIVE

The purpose of our study is to investigate the effectiveness of ZeroPhobia: Aviophobia (a self-help mobile app-based treatment) in reducing flight anxiety symptoms and depressive and anxiety symptoms. We will also investigate the effects of usage intensity, the sense of immersion, inherent absorption ability, and perceived user-friendliness on the treatment effect.

METHODS

Participants (N=114) who are aged 18-64 years and experience at least mild symptoms of aviophobia will be recruited from the general Dutch population and randomized into a treatment group or waitlist control group. By using their own phones and rudimentary mobile virtual reality headsets, participants will receive six modules of psychoeducation and cognitive behavioral therapy, which will include six levels of virtual reality exposure therapy over a period of 6 weeks. Assessments will be conducted at baseline, posttest (ie, after 6 weeks), and 3- and 12-month follow-ups. The primary outcome measure of our study is the Flight Anxiety Situations Questionnaire. The secondary outcome measures include anxiety and depression measures and additional covariates (including usage intensity, the degree of immersion, etc). We will test treatment effectiveness by conducting an intention-to-treat analysis and estimating average treatment effects on the treated. The mechanisms of treatment effect will also be explored.

RESULTS

The study was funded on September 25, 2018. Ethical approval was received on October 11, 2019. Recruitment closed on May 7, 2020.

CONCLUSIONS

Our study will further the scientific understanding and clinical implications of technology's current ability to aid in providing effective, accessible treatment for the fear of flying.

TRIAL REGISTRATION

Netherlands Trial Registry NL70238.029.19; https://www.trialregister.nl/trial/8257.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/22008.

An Internet-based treatment for Flying Phobia using 360° images: Study protocol for a feasibility pilot study

BACKGROUND

Flying Phobia (FP) is a prevalent disorder that can cause serious interference in a person's life. ICBT interventions have already shown their efficacy in several studies, but studies in the field of specific phobias are still scarce. Moreover, few studies have investigated the feasibility of using different types of images in exposure scenarios in ICBTs and no studies have been carried out on the role of sense of presence and reality judgement. The aim of the present study is to explore the feasibility of an ICBT for FP (NO-FEAR Airlines) using two types of images with different levels of immersion (still and navigable images). A secondary aim is to explore the potential effectiveness of the two experimental conditions using two types of images compared to a waiting list control group. Finally, the role of navigable images compared to the still images in the level of anxiety, sense of presence, and reality judgement will also be explored. This paper presents the study protocol.

METHODS

This study is a three-armed feasibility pilot study with the following conditions: NO-FEAR Airlines with navigable images, NO-FEAR Airlines with still images, and a waiting list group. A minimum of 60 participants will be recruited. The intervention will have a maximum duration of 6 weeks. Measurements will be taken at four different moments: baseline, post-intervention, and two follow-ups (3- and 12-month). Participants' opinions, preference, satisfaction and acceptance regarding the images used in the exposure scenarios will be assessed. FP symptomatology outcomes will also be considered for secondary analyses. The anxiety, sense of presence, and reality judgement in the exposure scenarios will also be analysed.

DISCUSSION

This study will conduct a pilot study on the feasibility of an ICBT for FP and it is the first one to explore the evaluation of patients of the two type of images (still and navigable) and the role of presence and reality judgement in exposure scenarios delivered through the Internet. Research in this field can have an impact on the way these scenarios are designed and developed, as well as helping to explore whether they have any effect on adherence.

TRIAL REGISTRATION

NCT03900559. Trial Registration date 3 April 2019, retrospectively registered.

The Cognitive-Emotional Design and Study of Architectural Space: A Scoping Review of Neuroarchitecture and Its Precursor Approaches

Humans respond cognitively and emotionally to the built environment. The modern possibility of recording the neural activity of subjects during exposure to environmental situations, using neuroscientific techniques and virtual reality, provides a promising framework for future design and studies of the built environment. The discipline derived is termed "neuroarchitecture". Given neuroarchitecture's transdisciplinary nature, it progresses needs to be reviewed in a contextualised way, together with its precursor approaches. The present article presents a scoping review, which maps out the broad areas on which the new discipline is based. The limitations, controversies, benefits, impact on the professional sectors involved, and potential of neuroarchitecture and its precursors' approaches are critically addressed.

Better, Virtually: the Past, Present, and Future of Virtual Reality Cognitive Behavior Therapy

Virtual reality (VR) is an immersive technology capable of creating a powerful, perceptual illusion of being present in a virtual environment. VR technology has been used in cognitive behavior therapy since the 1990s and accumulated an impressive evidence base, yet with the recent release of consumer VR platforms came a true paradigm shift in the capabilities and scalability of VR for mental health. This narrative review summarizes the past, present, and future of the field, including milestone studies and discussions on the clinical potential of alternative embodiment, gamification, avatar therapists, virtual gatherings, immersive storytelling, and more. Although the future is hard to predict, clinical VR has and will continue to be inherently intertwined with what are now rapid developments in technology, presenting both challenges and exciting opportunities to do what is not possible in the real world.

Emotion Recognition in Immersive Virtual Reality: From Statistics to Affective Computing

Emotions play a critical role in our daily lives, so the understanding and recognition of emotional responses is crucial for human research. Affective computing research has mostly used non-immersive two-dimensional (2D) images or videos to elicit emotional states. However, immersive virtual reality, which allows researchers to simulate environments in controlled laboratory conditions with high levels of sense of presence and interactivity, is becoming more popular in emotion research. Moreover, its synergy with implicit measurements and machine-learning techniques has the potential to impact transversely in many research areas, opening new opportunities for the scientific community. This paper presents a systematic review of the emotion recognition research undertaken with physiological and behavioural measures using head-mounted displays as elicitation devices. The results highlight the evolution of the field, give a clear perspective using aggregated analysis, reveal the current open issues and provide guidelines for future research.

Analysis of Usage Data from a Self-Guided App-Based Virtual Reality Cognitive Behavior Therapy for Acrophobia: A Randomized Controlled Trial

This study examined user engagement with ZeroPhobia, a self-guided app-based virtual reality (VR) Cognitive Behavior Therapy for acrophobia symptoms using cardboard VR viewers. Dutch acrophobic adults (n = 96) completed assessments at baseline and immediately following treatment. Primary outcome measures were the Acrophobia Questionnaire (AQ) and the Igroup Presence Questionnaire (IPQ). Usage data consisted of number of VR sessions practiced, practice time, and fear ratings directly after practicing. Results show that of the 66 participants who played at least one level, the majority continued to finish all levels, spending on average 24.4 min in VR. Self-reported fear consistently decreased between the start and finish of levels. Post-test AQ scores depended quadratically on time spent in VR. Higher pre-test AQ scores were significantly associated with subjective anxiety after the first level and a reduction of post-test AQ scores, but not with number of sessions, suggesting it might be more beneficial to play one level for a longer time period instead of practicing many VR levels. Results also show an optimum exposure level at which increasing practice time does not result in increased benefit. Self-guided VR acrophobia treatment is effective and leads to consistent reductions in self-reported anxiety both between levels and after treatment. Most participants progressed effectively to the highest self-exposure level, despite the absence of a therapist.

Experiences of Gamified and Automated Virtual Reality Exposure Therapy for Spider Phobia: Qualitative Study

Background

Virtual reality exposure therapy is an efficacious treatment of anxiety disorders, and recent research suggests that such treatments can be automated, relying on gamification elements instead of a real-life therapist directing treatment. Such automated, gamified treatments could be disseminated without restrictions, helping to close the treatment gap for anxiety disorders. Despite initial findings suggesting high efficacy, very is little is known about how users experience this type of intervention.

Objective

The aim of this study was to examine user experiences of automated, gamified virtual reality exposure therapy using in-depth qualitative methods.

Methods

Seven participants were recruited from a parallel clinical trial comparing automated, gamified virtual reality exposure therapy for spider phobia against an in vivo exposure equivalent. Participants received the same virtual reality treatment as in the trial and completed a semistructured interview afterward. The transcribed material was analyzed using thematic analysis.

Results

Many of the uncovered themes pertained directly or indirectly to a sense of presence in the virtual environment, both positive and negative. The automated format was perceived as natural and the gamification elements appear to have been successful in framing the experience not as psychotherapy devoid of a therapist but rather as a serious game with a psychotherapeutic goal.

Conclusions

Automated, gamified virtual reality exposure therapy appears to be an appealing treatment modality and to work by the intended mechanisms. Findings from the current study may guide the next generation of interventions and inform dissemination efforts and future qualitative research into user experiences.

Questionnaire Measures and Physiological Correlates of Presence: A Systematic Review

The published literature has produced several definitions for the sense of presence in a simulated environment, as well as various methods for measuring it. The variety of conceptualizations makes it difficult for researchers to interpret, compare, and evaluate the presence ratings obtained from individual studies. Presence has been measured by employing questionnaires, physiological indices, behavioral feedbacks, and interviews. A systematic literature review was conducted to provide insight into the definitions and measurements of presence in studies from 2002 to 2019, with a focus on questionnaires and physiological measures. The review showed that scholars had introduced various definitions of presence that often originate from different theoretical standpoints and that this has produced a multitude of different questionnaires that aim to measure presence. At the same time, physiological studies that investigate the physiological correlates of the sense of presence have often shown ambiguous results or have not been replicated. Most of the scholars have preferred the use of questionnaires, with Witmer and Singer's Presence Questionnaire being the most prevalent. Among the physiological measures, electroencephalography was the most frequently used. The conclusions of the present review aim to stimulate future structured efforts to standardize the use of the construct of presence, as well as inspire the replication of the findings reported in the published literature.

Too Real to Be Virtual: Autonomic and EEG Responses to Extreme Stress Scenarios in Virtual Reality

The evolution of virtual reality (VR) technologies requires setting boundaries of its use. In this study, 3 female participants were experiencing VR scenarios with stressful content and their activity of the autonomic nervous system and EEG were recorded. It has been discovered that virtual reality can evoke acute stress reactions accompanied by activation of the sympathetic nervous system and a decrease in the activity of the parasympathetic nervous system. The high-stress response is accompanied by a decrease in the power of the EEG, and, on the contrary, the activation of the avoidance reaction is accompanied by an increase in the power of the EEG alpha waves. Therefore, the use of stressful VR content can cause high emotional stress to a user and restrictions should be considered.

Being present in a real or virtual world: A EEG study

BACKGROUND AND OBJECTIVE

This study proposes an approach to evaluation and measuring of presence for man-machine interaction in the virtual reality based on electroencephalographic data.

MATERIALS AND METHODS

It analyzes stable electroencephalographic patterns that allow us to trace a connection between a brain activity and purposeful actions of an individual in various environments. The subjects of the study were experienced downhill skiers equipped with electroencephalographs, who performed real-life skiing on a downhill course, after which they were offered a virtual simulation of downhill skiing using an HTCVive headset and a programmed 2D or desktop simulator.

RESULTS

The results of measurement showed neuropatterns similar in the cases of virtual reality simulation and physical downhill skiing (in part of changes in space and power parameters of electroencephalograms in the different frequency ranges) and different from a 2D simulator. This observation enables us to make an assumption of realism of a virtual reality simulator in the context of reproduction of the subjects' similar cognitive and semantic connections and motor programs.

DISCUSSION

Further research work will focus on evaluation of efficiency in performing psychophysiological tests (time response to a mobile object) in the virtual reality and 2D desktop application.

Virtual Reality for Anxiety Disorders: Rethinking a Field in Expansion

The principal aim to this chapter is to present the latest ideas in virtual reality (VR), some of which have already been applied to the field of anxiety disorders, and others are still pending to be materialized. More than 20 years ago, VR emerged as an exposure tool in order to provide patients and therapists with more appealing ways of delivering a technique that was undoubtedly effective but also rejected and thus underused. Throughout these years, many improvements were achieved. The first section of the chapter describes those improvements, both considering the research progresses and the applications in the real world. In a second part, our main interest is to expand the discussion of the new applications of VR beyond its already known role as an exposure tool. In particular, VR is enabling the materialization of numerous ideas that were previously confined to a merely philosophical discussion in the field of cognitive sciences. That is, VR has the enormous potential of providing feasible ways to explore nonclassical ways of cognition, such as embodied and situated information processing. Despite the fact that many of these developments are not fully developed, and not specifically designed for anxiety disorders, we want to introduce these new ideas in a context in which VR is experiencing an enormous transformation.

Virtual reality exposure therapy for adolescents with fear of public speaking: a non-randomized feasibility and pilot study

BACKGROUND

Public Speaking Anxiety (PSA) is a common anxiety with onset in adolescence and early adulthood. With the advent of consumer virtual reality (VR) technology, VR-delivered exposure therapy is now a scalable and practical treatment option and has previously been shown to be efficacious with adults. In this non-randomized feasibility and pilot trial, we explore the effect of one-session (90 min) VR-delivered exposure therapy for adolescents (aged 13-16) with PSA.

METHODS

A total of 27 adolescents were recruited from Norwegian high schools and completed self-report measures of PSA twice prior to treatment, 1 week after treatment, and at 1 and 3 month follow-up. Heart rate was recorded during the treatment session. A low-cost head-mounted VR display with a custom-built VR stimuli material depicting a cultural and age appropriate classroom and audience were used when a series of speech (exposure exercises) were performed.

RESULTS

Linear mixed effects model revealed a significant decrease in PSA symptoms (Cohen's d = 1.53) pre-post treatment, and improvements were maintained at follow-ups. Physiological data revealed a small increase in heart rate during exposure tasks. Based on feedback from the adolescents, the feasibility of the intervention was increased during the trial.

CONCLUSIONS

The results show that low-cost, consumer VR hardware can be used to deliver efficacious treatment for PSA in adolescents, in a feasible one-session format.

Heat pain modulation with virtual water during a virtual hand illusion

Immersive virtual reality is a powerful method to modify the environment and thereby influence experience. The present study used a virtual hand illusion and context manipulation in immersive virtual reality to examine top-down modulation of pain. Participants received painful heat stimuli on their forearm and placed an embodied virtual hand (co-located with their real one) under a virtual water tap, which dispensed virtual water under different experimental conditions. We aimed to induce a temperature illusion by a red, blue or white light suggesting warm, cold or no virtual water. In addition, the sense of agency was manipulated by allowing participants to have high or low control over the virtual hand's movements. Most participants experienced a thermal sensation in response to the virtual water and associated the blue and red light with cool/cold or warm/hot temperatures, respectively. Importantly, the blue light condition reduced and the red light condition increased pain intensity and unpleasantness, both compared to the control condition. The control manipulation influenced the sense of agency, but did not influence pain ratings. The large effects revealed in our study suggest that context effects within an embodied setting in an immersive virtual environment should be considered within VR based pain therapy.

Behavioral realism and lifelike psychophysiological responses in virtual reality by the example of a height exposure

Virtual reality (VR) is increasingly gaining importance as a valuable methodical tool for psychological research. The greatest benefit of using VR is generating rich, complex and vivid, but still highly controllable settings. As VR has been found to elicit lifelike psychophysiological and emotional responses, we examined by means of a height exposure whether VR resembles physical reality to the necessary degree to constitute a suitable framework for investigating real-life behavior in a controlled experimental context. As hypothesized, participants behaved in VR exactly as would be appropriate in a real environment: Being exposed to great height, participants walked significantly slower across a virtual steel girder construction protruding from a high-rise building as compared to participants who traversed the very same construction on the ground level. In the height condition, this realistic behavior could be predicted on basis of the participants' trait anxiety. Aligned with the behavioral responses, they showed realistic psychophysiological responses, i.e., an elevated heart rate when exposed to height. Interestingly, participants of the height condition reported a greater sense of presence, which indicates that emotions have an elevating effect on presence. As a conclusion, our findings provide further evidence that VR evokes lifelike responses at both behavioral and psychophysiological level and therefore increases ecological validity of psychological experiments.