Head-Mounted Displays for Clinical Virtual Reality Applications: Pitfalls in Understanding User Behavior while Using Technology

Comparison between wrap around screens and a head mounted display on driver muscle and kinematic responses to a pedestrian hazard

As driving performance relies heavily on the interpretation of visual information, driving simulators require a visual display that can effectively communicate the virtual environment to the driver. Most high-fidelity visual displays include an expensive system of high-definition projectors and wraparound screens. To reduce the overall cost of a driving simulator while preserving the generalizability of results to naturalistic driving, head mounted displays (HMD) are being considered as a substitute visual cueing system. Recent innovations to virtual reality technologies are encouraging, however, differences between HMDs and more traditional visual displays have not been explored for all types of driving measures. In particular, while existing literature provides insight into the validity of HMDs as a substitute for higher fidelity visual displays in tests of driver behaviour and performance, there is a gap in the literature regarding differences in physiological responses. In the current study, upper body muscle activation and joint angle ranges were compared between an Oculus™ Rift Development Kit 2 HMD and a system of wrap around screens. Twenty-one participants each completed two simulated drives, one per display, in a counterbalanced order. During the simulation, drivers encountered unanticipated pedestrian crossings during which peak surface electromyography, root-mean-square of the surface electromyography signal and joint angles were determined bilaterally on the upper limbs. No significant differences (p ≤ 0.05) were observed between the Oculus™ Rift HMD and the wrap around screens for all dependent variables with the exception of left joint range of motion in female participants, suggesting that the HMD reduced field of view had a minimal effect on driver kinematics and no effect on muscle activation levels. Upper body bracing was observed during the hazard response time segments characterized by significantly increased muscle activity during hazard response time segments and minimal joint movement. Considering the lack of significant kinematic and muscle activation differences between the two visual inputs, HMD technology for hazard response may provide a suitable alternative to wrap around screens for studying kinematic responses during hazardous driving scenarios.

The Effects of Acute Virtual Reality Exergaming on Mood and Executive Function: Exploratory Crossover Trial

Background

Virtual reality (VR) exergaming is a new intervention strategy to help humans engage in physical activity to enhance mood. VR exergaming may improve both mood and executive function by acting on the prefrontal cortex, expanding the potential benefits. However, the impact of VR exergaming on executive function has not been fully investigated, and associated intervention strategies have not yet been established.

Objective

This study aims to investigate the effects of 10 minutes of VR exergaming on mood and executive function.

Methods

A total of 12 participants played the exergame “FitXR” under 3 conditions: (1) a VR exergame condition (ie, exercise with a head-mounted display condition [VR-EX]) in which they played using a head-mounted display, (2) playing the exergame in front of a flat display (2D-EX), and (3) a resting condition in which they sat in a chair. The color-word Stroop task (CWST), which assesses executive function; the short form of the Profile of Mood States second edition (POMS2); and the short form of the Two-Dimensional Mood Scale (TDMS), which assess mood, were administered before and after the exercise or rest conditions.

Results

The VR-EX condition increased the POMS2 vigor activity score (rest and VR-EX: t₁₁=3.69, P=.003) as well as the TDMS arousal (rest vs 2D-EX: t₁₁=5.34, P<.001; rest vs VR-EX: t₁₁=5.99, P<.001; 2D-EX vs VR-EX: t₁₁=3.02, P=.01) and vitality scores (rest vs 2D-EX: t₁₁=3.74, P=.007; rest vs VR-EX: t₁₁=4.84, P=.002; 2D-EX vs VR-EX: t₁₁=3.53, P=.006), suggesting that VR exergaming enhanced mood. Conversely, there was no effect on CWST performance in either the 2D-EX or VR-EX conditions. Interestingly, the VR-EX condition showed a significant positive correlation between changes in CWST arousal and reaction time (r=0.58, P=.046). This suggests that the effect of exergaming on improving executive function may disappear under an excessively increased arousal level in VR exergaming.

Conclusions

Our findings showed that 10 minutes of VR exergaming enhanced mood but did not affect executive function. This suggests that some VR content may increase cognitive demands, leading to psychological fatigue and cognitive decline as an individual approaches the limits of available attentional capacity. Future research must examine the combination of exercise and VR that enhances both brain function and mood.

Effects of virtual reality in post-stroke aphasia: a systematic review and meta-analysis

OBJECTIVE

To investigate whether virtual reality (VR) interventions have beneficial effects on the functional communication and language function of patients with post-stroke aphasia (PSA).

METHODS

We searched nine electronic literature databases and two clinical registry platforms to identify randomized controlled trials (RCTs) and quasi-RCTs performed up to September 2020. Screening, quality assessment, and data collection were performed by two authors independently, using standard protocols. Data aggregation and risk of bias evaluation were conducted using Review Manager Version 5.4. The quality of evidence was evaluated with GRADEpro.

RESULTS

A total of five studies involving 121 participants met the inclusion criteria and were appraised. Four studies were included in the quantitative synthesis. VR reduced the severity of language impairment with borderline significance [SMD (95%CI) = 0.70[0.01, 1.39], P=0.05]. The meta-analysis showed no statistical difference in functional communication [SMD (95%CI) =0.41[-0.29, 1.12], P=0.25], word finding [SMD (95%CI) =0.42[-0.24, 1.08], P=0.21], and repetition [SMD (95%CI) =0.16[-0.62, 0.94], P=0.68] between VR group and the control group.

CONCLUSION

This review demonstrated a borderline positive clinical effect of VR for the severity of language impairment when compared with conventional rehabilitation therapy. Conversely, VR had no effect on functional communication, word finding, and repetition. Further research is warranted to reach more definite conclusions.

Does virtual reality attract visitors? The mediating effect of presence on consumer response in virtual reality tourism advertising

An experimental study was conducted to test the mediating effect of presence on the consumer response to tourism promotion using virtual reality (VR) technology. Hong Kong college students (N = 203) were assigned to three experimental groups in which they were exposed to a hotel advertorial on an online blog, a VR 360° video on a mobile phone, or a VR 360° video using Google Cardboard goggles. The results supported the hypothesis that presence plays a mediating role in the relationship between the use of VR in tourism advertising and consumer response. As one of the first studies in the tourism field to investigate the effects of a virtual depiction of a real-world environment on consumption intentions, the findings reveal how VR technology can be used to promote a hotel by generating a sense of presence. This study makes a further contribution to the VR literature by finding that the use of Cardboard goggles did not produce a significantly greater sense of presence in the experience of advertorial viewers. The theoretical contributions and practical implications of the findings for the use of VR technology in branding and promotion are discussed.

Acceptance of immersive head-mounted virtual reality in older adults

Immersive virtual reality has become increasingly popular to improve the assessment and treatment of health problems. This rising popularity is likely to be facilitated by the availability of affordable headsets that deliver high quality immersive experiences. As many health problems are more prevalent in older adults, who are less technology experienced, it is important to know whether they are willing to use immersive virtual reality. In this study, we assessed the initial attitude towards head-mounted immersive virtual reality in 76 older adults who had never used virtual reality before. Furthermore, we assessed changes in attitude as well as self-reported cybersickness after a first exposure to immersive virtual reality relative to exposure to time-lapse videos. Attitudes towards immersive virtual reality changed from neutral to positive after a first exposure to immersive virtual reality, but not after exposure to time-lapse videos. Moreover, self-reported cybersickness was minimal and had no association with exposure to immersive virtual reality. These results imply that the contribution of VR applications to health in older adults will neither be hindered by negative attitudes nor by cybersickness.

Within- and Between-Session Prefrontal Cortex Response to Virtual Reality Exposure Therapy for Acrophobia

Exposure Therapy (ET) has demonstrated its efficacy in the treatment of phobias, anxiety and Post-traumatic Stress Disorder (PTSD), however, it suffers a high drop-out rate because of too low or too high patient engagement in treatment. Virtual Reality Exposure Therapy (VRET) is comparably effective regarding symptom reduction and offers an alternative tool to facilitate engagement for avoidant participants. Neuroimaging studies have demonstrated that both ET and VRET normalize brain activity within a fear circuit. However, previous studies have employed brain imaging technology which restricts people's movement and hides their body, surroundings and therapist from view. This is at odds with the way engagement is typically controlled. We used a novel combination of neural imaging and VR technology-Functional Near-Infrared Spectroscopy (fNIRS) and Immersive Projection Technology (IPT), to avoid these limitations. Although there are a few studies that have investigated the effect of VRET on a brain function after the treatment, the present study utilized technologies which promote ecological validity to measure brain changes after VRET treatment. Furthermore, there are no studies that have measured brain activity within VRET session. In this study brain activity within the prefrontal cortex (PFC) was measured during three consecutive exposure sessions. N = 13 acrophobic volunteers were asked to walk on a virtual plank with a 6 m drop below. Changes in oxygenated (HbO) hemoglobin concentrations in the PFC were measured in three blocks using fNIRS. Consistent with previous functional magnetic resonance imaging (fMRI) studies, the analysis showed decreased activity in the DLPFC and MPFC during first exposure. The activity increased toward normal across three sessions. The study demonstrates potential efficacy of a method for measuring within-session neural response to virtual stimuli that could be replicated within clinics and research institutes, with equipment better suited to an ET session and at fraction of the cost, when compared to fMRI. This has application in widening access to, and increasing ecological validity of, immersive neuroimaging across understanding, diagnosis, assessment and treatment of, a range of mental disorders such as phobia, anxiety and PTSD or addictions.

Application of virtual environments in a multi-disciplinary day neurorehabilitation program to improve executive functioning using the Stroop task

BACKGROUND

Virtual reality (VR) technology has demonstrated usefulness in diagnosis, education, and training. Studies supporting use of VR as a therapeutic treatment in medical rehabilitation settings remain limited. This study examines the use of VR in a treatment capacity, and whether it can be effectively integrated into neurorehabilitation.

OBJECTIVE

To determine whether immersive VR treatment interventions improve executive dysfunction in patients with brain injury and whether performance is stronger on a VR version of the Stroop than traditional Stroop formats.

METHODS

15 patients with brain injury admitted to day neurorehabilitation.

OUTCOME MEASURES

reaction time, inhibition, and accuracy indices on VR Stroop; Automated Neuropsychological Assessment Metrics (ANAM) Stroop, Delis-Kaplan Executive Function System Stroop, Golden Stroop, and Woodcock-Johnson, 3rd Edition (WJ-III): Pair Cancellation.

RESULTS

Participants demonstrated significantly reduced response time on the word-reading condition of VR Stroop and non-significantly reduced response time on the interference condition. Non-significant improvements in accuracy and inhibition were demonstrated on the color-naming condition of VR Stroop. Significantly improved accuracy under time pressure was found for the ANAM, after VR intervention.

CONCLUSION

Implementation of immersive VR interventions during neurorehabilitation is effective in improving specific executive functions and information processing speed in brain-injured patients during the subacute period.

Immersion of virtual reality for rehabilitation - Review

Virtual reality (VR) shows promise in the application of healthcare and because it presents patients an immersive, often entertaining, approach to accomplish the goal of improvement in performance. Eighteen studies were reviewed to understand human performance and health outcomes after utilizing VR rehabilitation systems. We aimed to understand: (1) the influence of immersion in VR performance and health outcomes; (2) the relationship between enjoyment and potential patient adherence to VR rehabilitation routine; and (3) the influence of haptic feedback on performance in VR. Performance measures including postural stability, navigation task performance, and joint mobility showed varying relations to immersion. Limited data did not allow a solid conclusion between enjoyment and adherence, but patient enjoyment and willingness to participate were reported in care plans that incorporates VR. Finally, different haptic devices such as gloves and controllers provided both strengths and weakness in areas such movement velocity, movement accuracy, and path efficiency.

Future Directions: How Virtual Reality Can Further Improve the Assessment and Treatment of Eating Disorders and Obesity

Transdisciplinary efforts for further elucidating the etiology of eating and weight disorders and improving the effectiveness of the available evidence-based interventions are imperative at this time. Recent studies indicate that computer-generated graphic environments-virtual reality (VR)-can integrate and extend existing treatments for eating and weight disorders (EWDs). Future possibilities for VR to improve actual approaches include its use for altering in real time the experience of the body (embodiment) and as a cue exposure tool for reducing food craving.

Virtual restorative environment therapy as an adjunct to pain control during burn dressing changes: study protocol for a randomised controlled trial

BACKGROUND

The pain of a severe burn injury is often characterised by intense background pain, coupled with severe exacerbations associated with essential procedures such as dressing changes. The experience of pain is affected by patients' psychological state and can be enhanced by the anxiety, fear and distress caused by environmental and visual inputs. Virtual Reality (VR) distraction has been used with success in areas such as burns, paediatrics and oncology. The underlying principle of VR is that attention is diverted from the painful stimulus by the use of engaging, dynamic 3D visual content and associated auditory stimuli. Functional magnetic resonance imaging (fMRI) studies undertaken during VR distraction from experimental pain have demonstrated enhancement of the descending cortical pain-control system.

METHODS/DESIGN

The present study will evaluate the feasibility of introducing a novel VR system to the Burns Unit at the Queen Elizabeth Hospital Birmingham for dressing changes: virtual restorative environment therapy (VRET). The study will also explore the system's impact on pain during and after the dressing changes compared to conventional analgesia for ward-based burn dressing changes. A within-subject crossover design will be used to compare the following three conditions: 1. Interactive VRET plus conventional analgesics. 2. Passive VRET with conventional analgesics. 3. Conventional analgesics alone. Using the Monte Carlo method, and on the basis of previous local audit data, a sample size of 25 will detect a clinically significant 33 % reduction in worst pain scores experienced during dressing changes.

DISCUSSION

The study accrual rate is currently slower than predicted by previous audits of admission data. A review of the screening log has found that recruitment has been limited by the nature of burn care, the ability of burn inpatients to provide informed consent and the ability of patients to use the VR equipment. Prior to the introduction of novel interactive technologies for patient use, the characteristics and capabilities of the target population needs to be evaluated, to ensure that the interface devices and simulations are usable.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN23330756 . Date of Registration 25 February 2014.

Using virtual reality driving simulators in persons with spinal cord injury: three screen display versus head mounted display

PURPOSE

Virtual reality (VR) is a relatively new technology that is currently utilized in a wide variety of settings to test and train individuals in specialized skills. This study examines methods for improving driver retraining protocols for persons with spinal cord injury (SCI).

METHOD

We compared a VR driving simulator, under two different display conditions, a head mounted display (HMD) and a three screen display (TSD) to identify the best method for retraining driving skills following SCI.

RESULTS

Although there was minimal evidence for driving performance difficulties in the HMD condition relative to the TSD condition (e.g. greater number of times for being off course and longer stopping latencies for the HMD condition), rates of simulator sickness did not differ between display conditions.

CONCLUSIONS

Taken together, findings suggest that both the HMD and the TSD are reasonable simulator options for driver retraining in SCI.