Virtual reality and applied psychophysiology

Simultaneous Application of Transcranial Direct Current Stimulation during Virtual Reality Exposure

Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that changes the likelihood of neuronal firing through modulation of neural resting membranes. Compared to other techniques, tDCS is relatively safe, cost-effective, and can be administered while individuals are engaged in controlled, specific cognitive processes. This latter point is important as tDCS may predominantly affect intrinsically active neural regions. In an effort to test tDCS as a potential treatment for psychiatric illness, the protocol described here outlines a novel procedure that allows the simultaneous application of tDCS during exposure to trauma-related cues using virtual reality (tDCS+VR) for veterans with posttraumatic stress disorder (NCT03372460). In this double-blind protocol, participants are assigned to either receive 2 mA tDCS, or sham stimulation, for 25 minutes while passively watching three 8-minute standardized virtual reality drives through Iraq or Afghanistan, with virtual reality events increasing in intensity during each drive. Participants undergo six sessions of tDCS+VR over the course of 2-3 weeks, and psychophysiology (skin conductance reactivity) is measured throughout each session. This allows testing for within and between session changes in hyperarousal to virtual reality events and adjunctive effects of tDCS. Stimulation is delivered through a built-in rechargeable battery-driven tDCS device using a 1 (anode) x 1 (cathode) unilateral electrode set-up. Each electrode is placed in a 3 x 3 cm (current density 2.22 A/m²) reusable sponge pocket saturated with 0.9% normal saline. Sponges with electrodes are attached to the participant's skull using a rubber headband with the electrodes placed such that they target regions within the ventromedial prefrontal cortex. The virtual reality headset is placed over the tDCS montage in such a way as to avoid electrode interference.

Tracing Physical Behavior in Virtual Reality: A Narrative Review of Applications to Social Psychology

Virtual reality (VR) offers unique benefits to social psychological research, including a high degree of experimental control alongside strong ecological validity, a capacity to manipulate any variable of interest, and an ability to trace the physical, nonverbal behavior of the user in a very fine-grained and automated manner. VR improves upon traditional behavioral measurement techniques (e.g., observation and coding) on several fronts as data collection is covert, continuous, passive, and occurs within a controlled context. The current review synthesizes extant methods for tracing physical behavior in VR, such as gaze tracking and interpersonal distance measurement, and describes how researchers have applied these methods to understand important phenomena within the context of social psychology. To date, primary areas of application have included the assessment of social approach and avoidance, social evaluation and bias, and engagement. The limitations of behavioral tracing methods in VR, as well as future directions for their continued application and extension, are discussed. This narrative review equips readers with a thorough understanding of behavioral tracing methods that can be implemented in VR, their benefits and drawbacks, the insight they may offer into social processes, and future avenues of work for applying emergent technologies to research questions in social psychology.

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

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

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

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

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

Combined transcranial direct current stimulation with virtual reality exposure for posttraumatic stress disorder: Feasibility and pilot results

BACKGROUND

Facilitating neural activity using non-invasive brain stimulation may improve extinction-based treatments for posttraumatic stress disorder (PTSD).

OBJECTIVE/HYPOTHESIS

Here, we examined the feasibility of simultaneous transcranial direct current stimulation (tDCS) application during virtual reality (VR) to reduce psychophysiological arousal and symptoms in Veterans with PTSD.

METHODS

Twelve Veterans with PTSD received six combat-related VR exposure sessions during sham-controlled tDCS targeting ventromedial prefrontal cortex. Primary outcome measures were changes in skin conductance-based arousal and self-reported PTSD symptom severity.

RESULTS

tDCS + VR components were combined without technical difficulty. We observed a significant interaction between reduction in arousal across sessions and tDCS group (p = .03), indicating that the decrease in physiological arousal was greater in the tDCS + VR versus sham group. We additionally observed a clinically meaningful reduction in PTSD symptom severity.

CONCLUSIONS

This study demonstrates feasibility of applying tDCS during VR. Preliminary data suggest a reduction in psychophysiological arousal and PTSD symptomatology, supporting future studies.

Skin Conductance Reactivity to Standardized Virtual Reality Combat Scenes in Veterans with PTSD

Interest in virtual reality (VR) as a clinical tool to augment posttraumatic stress (PTSD) treatment has grown substantially in recent years due to advances in VR technology. Moreover, its potential assisted use in the PTSD diagnostic process has been recognized. In this study we examined physiological responding, skin conductance, to a standardized presentation of non-personalized combat-related VR events (e.g. encountering enemy fire; explosions) as compared to non-combat classroom VR events in 19 Veterans with and 24 Veterans without combat-related PTSD who had been deployed to Iraq and Afghanistan. Veterans watched a total of 12 VR scenarios-six combat-related and six non-combat-related-with each scenario gradually increasing in emotional intensity by adding more VR events in addition to repeating prior VR events. Results show that Veterans with PTSD displayed larger skin conductance reactivity across VR combat events, but not for non-combat VR events, as compared to combat Veterans without PTSD. Nevertheless, Veterans with and without PTSD showed a similar reduction of emotional arousal to repeated presentation of the same VR combat events. Within the PTSD sample, the elevated level of VR combat-related arousal correlated marginally with severity of hyperarousal symptoms. This study confirms that the use of a non-personalized and standardized VR presentation successfully distinguishes Veterans with PTSD from those without on a measure of psychophysiological arousal to combat-related VR stimuli. The assessment of physiological reactivity during the repeated presentation of standardized, trauma-related VR events highlights its use for PTSD assessment as well as treatment.

Virtual reality exposure therapy for fear of driving: analysis of clinical characteristics, physiological response, and sense of presence

OBJECTIVE

To investigate the reactions of women with driving phobia to a therapeutic program of scheduled virtual reality exposure treatment (VRET) sessions.

METHODS

The study intervention consisted of a computer game with car-driving scenarios that included several traffic situations. We investigated the participants' sense of presence, subjective distress, and physiological responses during eight virtual-reality exposures. We also evaluated clinical characteristics, driving cognitions, and quality of life in the participants.

RESULTS

Thirteen women were selected. Eight were able to complete the protocol. After VRET, there was a decrease in the frequency of distorted thoughts and state anxiety scores, as well as a slight improvement in quality of life. Subjective discomfort scores, heart rate variation, and sense of presence scores confirmed that there was sense of presence in the virtual reality environment.

CONCLUSION

All patients showed some degree of improvement and demonstrated different levels of anxiety in subsequent in vivo driving experiences. Our findings suggest that VRET could be used to facilitate in vivo exposure, because it can induce presence/immersion and reduce anxiety in patients with specific phobia. Furthermore, VRET is not associated with any type of risk.

The Potential of Virtual Reality for the Investigation of Awe

The emotion of awe is characterized by the perception of vastness and a need for accommodation, which can include a positive and/or negative valence. While a number of studies have successfully manipulated this emotion, the issue of how to elicit particularly intense awe experiences in laboratory settings remains. We suggest that virtual reality (VR) is a particularly effective mood induction tool for eliciting awe. VR provides three key assets for improving awe. First, VR provides users with immersive and ecological yet controlled environments that can elicit a sense of “presence,” the subjective experience of “being there” in a simulated reality. Further, VR can be used to generate complex, vast stimuli, which can target specific theoretical facets of awe. Finally, VR allows for convenient tracking of participants’ behavior and physiological responses, allowing for more integrated assessment of emotional experience. We discussed the potential and challenges of the proposed approach with an emphasis on VR’s capacity to raise the signal of reactions to emotions such as awe in laboratory settings.

Psychophysiology to Assess Impact of Varying Levels of Simulation Fidelity in a Threat Environment

There are many virtual environments found in the serious game community that simulate real world scenarios. There is a broad range of fidelity and experimental controls among these serious games. An important component to most evaluations is the extent to which level of fidelity impacts the persons immersed in the serious game. While a great deal of virtual environment and serious game research has assessed the subjective state or feeling of the participant (e.g., the participant’s sense of presence) through the use of questionnaires, the current study examines participant experience by examining psychophysiological responses of participants to their surroundings. The primary goal in this study was evaluative: will a virtual environment with arousing contents result in increased sensory arousal if it is presented in a highly immersive configuration? A secondary goal of this study was to investigate the utility of our environment to offer varying levels of stimulus threat to impact the user’s experience of the virtual environment. Increased simulation fidelity in an arousing environment resulted in faster heart rates and increased startle eyeblink amplitudes, suggesting that higher fidelity scenarios had great efficacy related to sensory arousal.

Neurocognitive and Psychophysiological Interfaces for Adaptive Virtual Environments

The use of neuropsychological and psychophysiological measures in studies of patients immersed in high-fidelity virtual environments offers the potential to develop current psychophysiological computing approaches into affective computing scenarios that can be used for assessment, diagnosis and treatment planning. Such scenarios offer the potential for simulated environments to proffer cogent and calculated response approaches to real-time changes in user emotion, neurocognition, and motivation. The value in using virtual environments to produce simulations targeting these areas has been acknowledged by an encouraging body of research. Herein the authors describe (1) literature on virtual environments for neurocognitive and psychophysiological profiles of users’ individual strengths and weaknesses; and (2) real-time adaptation of virtual environments that could be used for virtual reality exposure therapy and cognitive rehabilitation. Specifically, the authors discuss their approach to an adaptive environment that uses the principles of flow, presence, neuropsychology, psychophysiology to develop a novel application for rehabilitative applications.

Not just fun and games: applications of virtual reality in the identification and rehabilitation of cognitive disorders of the elderly

PURPOSE

To outline the evidence in the published medical literature suggesting the potential applications of virtual reality (VR) for the identification and rehabilitation of cognitive disorders of the elderly.

METHOD

Non-systematic literature review.

RESULTS

VR, despite its more common usage by younger persons, is a potentially promising source of techniques useful in the identification and rehabilitation of cognitive disorders of the elderly. Systems employing VR can include desktop and head-mounted visual displays among other devices. Thus far, published studies have described VR-based applications in the identification and treatment of deficits in navigational skills in ambulation and driving. In addition, VR has been utilised to enhance the ability to perform activities of daily living in patients with dementia, stroke, and Parkinson's Disease. Such investigations have thus far been small, and unblinded.

CONCLUSIONS

VR-based applications can potentially offer more versatile, comprehensive, and safer assessments of function. However, they also might be more expensive, complex and more difficult to use by elderly patients. Side effects of head-mounted visual displays include nausea and disorientation, but, have not been reported specifically in older subjects.

Virtual reality exposure therapy in the treatment of driving phobia

A growing number of researches has appeared on virtual reality exposure therapy (VRET) to treat anxiety disorders. The purpose of this article was to review some evidences that support the VRET efficacy to treat driving phobia. The studies were identified through computerized search (PubMed/Medline, Web of Science, and Scielo databases) from 1984 to 2007. Some findings are promising. Anxiety/avoidance ratings declined from pre to post-treatment. VRET may be used as a first step in the treatment of driving phobia, as long as it may facilitate the in vivo exposure, thus reducing risks and high costs of such exposure. Notwithstanding, more randomized/controlled clinical trials are required to prove its efficacy.

Virtual reality as a mechanism for exposure therapy

Virtual reality (VR) is as effective in inducing emotional responses as reality and its application is extremely valuable in exposure treatment. In virtual environments, the patients experience similar physiological symptoms and fear as they do in real life situations, thereby facilitating the habituation process. Our goal is to offer an overview of the current panorama of VR and psychotherapy, underlining the (virtual) exposure technique and the studies that focus on panic disorder treatment through the use of VR. The literature was revised through consultation to the ISI and PubMed databases. Virtual exposure treatment offers good results and great patient acceptability. However, despite the importance of this data for the evaluation of treatment efficacy, only a few studies measure physiological responses during exposure. Lack of controlled studies and standardized treatment protocols were observed. Despite the great advance of VR use in psychotherapy, a great deal of its potential is still unknown, therefore requiring the creation of new virtual environments so that controlled studies regarding its clinical application can be conducted. Throughout the process of elaboration and investigation, clinical experiences in virtual environments must be related to real experiences in a flexible context that combines relevant cultural, physical and cognitive aspects.