Comparing a virtual reality head-mounted display to on-screen three-dimensional visualization and two-dimensional computed tomography data for training in decision making in hepatic surgery: a randomized controlled study

Background: It is well established that regular participation in exercise and virtual reality (VR) environments are important tools for improving or maintaining human health and cognitive function. Objectives: This study examined the effects of acute exercise and VR environments on children’s memory function and exercise preference (i.e. cycling with or without the use of VR technology). Methods: Α 2×3 factorial design was adopted with two measures (pre, post) and three study groups. Forty-five healthy children aged 9 to 13 years (Mage = 10.91±1.24 years) voluntarily participated in the study. Participants were randomly assigned into three groups receiving different treatment: (1) an exercise+VR group that cycled for 15 min in a VR environment (forest path) combined with basic mathematical problem-solving tasks, (2) an exercise group that cycled for 15 min, and (3) a no-exercise group that sat in a specific place in a lab for 15 min (the control group). Before and after the acute exercise, all the groups completed the Sternberg Memory Task. Upon completion of the intervention, the two exercise groups completed measures of enjoyment, intention and attitudes towards cycling. The exercise+VR group also completed a scale capturing the VR’s usability. Results: The results show that the exercise group scored higher on Sternberg’s Memory Task (p .05) after the acute exercise treatment (post) than before it (pre). Similarly, the exercise+VR participants scored higher on the post-intervention memory task than did the exercise and control groups (p .05). Moreover, the exercise+VR group reported higher scores on enjoyment, intention and attitude towards cycling than the exercise group, but this difference was not statistically significant (p .05). Finally, the exercise+VR participants recorded high scores on the usability of the VR system during the acute exercise programme. Conclusions: These findings are in line with those of previous studies, underlining the important roles of exercise and VR environments on youths’ cognitive function.

The objective of this study was to construct systems for haptic virtual reality (VR) environment and to conduct an experiment to compare muscular activity during ball catching tasks in real and VR environments, where the level of the presence was evaluated. A ball catching task was demonstrated in two environments, where head-mounted display and SPIDAR-HS, the haptic presentation device using tensile force of the wire, were applied for constructing VR environment. As an index of dynamic muscular activity, forearm EMG signals were measured in the time course of a ball catching task. Average peak RMS value for forearm EMG in VR environment was 45.2% smaller than that in real environment. This difference was apparent because the amount of force generated by SPIDAR-HS was relatively lower than that made by the gravity force of the ball. On the other hand, the trends in dynamic muscular activities were similar for both environment, indicating that two tasks were fairly unique regardless the type of environments. It was concluded that the presence of VR was observable by the dynamic muscular changes during VR tasks with further adjustment of force levels required for the task in VR environment.

Background Freezing of gait (FoG) is a common target of rehabilitative interventions for people with Parkinson disease (PD). Virtual reality (VR) holds potential for advancing research and clinical management of FoG through flexible creation of FoG-provoking environments that are not easily or safely replicated in the clinic. Objective The aim of this study was to investigate whether VR environments that replicate FoG-provoking situations would exacerbate gait impairments associated with FoG compared to unobstructed VR and physical laboratory environments. Methods Gait characteristics (pace, rhythm, variability, asymmetry, and postural control domains) and festination were measured using motion capture while people with PD walked in VR environments based on FoG-provoking situations (doorway, hallway, and crowd environments) compared to unobstructed VR and physical laboratory environments. The effect of VR environments was assessed using one-way repeated measures ANOVAs with planned contrasts. Results Ten participants (mean age 74.1 years, 3 females, Hoehn and Yahr stage 2–3) with PD who self-reported FoG participated. Gait speed and step length were reduced in all VR environments compared to the physical laboratory. Step width was wider, step length was more variable, and festination was more common for some of the VR environments compared to the physical laboratory environment. Compared to the unobstructed virtual laboratory environment, step length was more variable in VR crowd and doorway environments. Conclusions The exacerbation of gait impairments that are characteristic precursors of FoG in FoG-provoking VR environments supports the potential utility of VR technology in the assessment and treatment of gait impairments in PD. Implications for rehabilitation Freezing increases fall risk and reduces quality of life in Parkinson disease (PD). Virtual reality (VR) can simulate visuospatial environments that provoke freezing. Immersive VR doorway, hallway, and crowd environments were developed. Gait speed slowed when people with PD walked overground in all VR environments. Step variability and festination increased in freeze-provoking environments.

The Development of Virtual Reality as a Tool to Investigate Eating Behavior

The absence of constraints is one of the major limitations in current Virtual Reality (VR) environments. Without constraints, it is difficult to perform precise 3D interactive manipulations in VR environments and precise solid modelling in VR environments cannot be guaranteed. In this paper, constraints are incorporated into the VR environment for intuitive and precise solid modelling. A hierarchically structured constraint-based data model is developed to support solid modelling in the VR environment. Solid modelling in the VR environment is precisely performed in an intuitive manner through constraint-based manipulations. Constraint-based manipulations are accompanied with automatic constraint recognition and precise constraint satisfaction to establish the hierarchically structured constraint-based data model and are realized by allowable motions for precise 3D interactions in the VR environment. The allowable motions are represented as a mathematical matrix for conveniently deriving allowable motions from constraints. A procedure-based degree-of-freedom incorporation approach for 3D constraint solving is presented for deriving the allowable motions. A rule-based constraint recognition engine is developed for both constraint-based manipulations and implicitly incorporating constraints into the VR environment. A prototype system has been implemented for precise solid modelling in an intuitive manner through constraint-based manipulations in the VR environment.

Virtual reality (VR) provides a completely digital world of interaction which enables the users to modify, edit, and transform digital elements in a responsive way. Mixed reality (MR), which is the result of blending the digital world and the physical world together, brings new advancements and challenges to human, computer and environment interactions. This paper focuses on adapting the already-existing methods and tools in architecture to both VR and MR environments under sustainable architectural design domain. For this purpose, we benefit from the semantically enriched data platforms of Building information modelling (BIM) tools, the performance calculation functions of building energy simulation tools while transcending these data into VR and MR environments. In this way, we were able to merge these diverse data for the virtual design activity. Nine participants have already tested the initial prototype of MR-based only interaction environment in our previous study [1]. According to the feedbacks, the user interface and interaction mechanisms were updated and the environment was made accessible also in VR. These updates made four types of interactions possible in MR and VR: 1) MR environment using HoloLens with gestures, 2) MR environment using HoloLens with a clicker, 3) VR environment using HTC Vive with two controllers, and 4) HoloLens emulator with a mouse. All these interaction cases were tested by 21 architecture students in an in-house workshop. In this workshop, we collected data on presence, usability, and technology acceptance of these cases. Our results show that interaction in a VR environment is the most natural interaction type and the participants were eager to use both MR and VR environments instead of an emulator. To our best of knowledge, this is the first comparative study of a BIM-based architectural design medium in both VR and MR environments.

Spatiotemporal gait deviations in a virtual reality environment

BackgroundAdolescent mental health is a national mental health emergency amid surging rates of anxiety and depression. Given the scarcity and lack of scalable mental health services, the use of self-administered, evidence-based technologies to support adolescent mental health is both timely and imperative.ObjectiveThe goal of this study was 2-fold: (1) to determine the feasibility, usability, and engagement of a participatory designed, nature-based virtual reality (VR) environment and (2) to determine the preliminary outcomes of our self-administered VR environment on depression, mindfulness, perceived stress, and momentary stress and mood.MethodsWe conducted a within-person, 3-week, in-home study with a community-based sample of 44 adolescents. Participants completed surveys of perceived stress, depression, cognitive fusion, and mindfulness at intake, postintervention, and a 3-week follow-up. Participants were invited to use a nature-based, VR environment that included 6 evidence-based activities 3 to 5 times per week. They completed momentary stress and mood surveys 5 times each day and before and after each VR session. Postintervention, participants completed surveys on system and intervention usability and their experiences with using the VR system. Quantitative data were analyzed using descriptive statistics and mixed effects modeling to explore the effect of the VR environment on stress. Qualitative data were analyzed using collaborative thematic analysis.ResultsParticipants’ use of the VR environment ranged from 1 session to 24 sessions (mean 6.27 sessions) at home over a 3-week period. The 44 participants completed all study protocols, indicating our protocol was feasible and the VR environment was engaging for most. Both the use of the VR system and novel VR intervention received strong usability ratings (mean 74.87 on the System Usability Scale). Most teens indicated that they found the tool to be easily administered, relaxing, and helpful with stress. For some, it offered space to process difficult emotions. The themes calm, regulating, and forget about everything resulted from open-ended exit interview data. Although the Relaxation Environment for Stress in Teens (RESeT) did not significantly affect repeated survey measurements of depression, mindfulness, nor cognitive fusion, it did positively affect momentary mood (pre-intervention: 10.8, post-intervention: 12.0, P=.001) and decrease momentary stress (pre-intervention: 37.9, post-intervention: 20.6, P=.001). We found a significant reduction in within-day momentary stress that strengthened with increased VR use over time during the study period (P=.03).ConclusionsThese preliminary data inform our own VR environment design but also provide evidence of the potential for self-administered VR as a promising tool to support adolescent mental health. Self-administered VR for mental health may be an effective intervention for reducing adolescent stress. However, understanding barriers (including disengagement) to using VR, as well as further encouraging participatory design with teens, may be imperative to the success of future mental health interventions.

ContextCurrent data visualization interfaces predominantly rely on 2-D screens. However, the emergence of virtual reality (VR) devices capable of immersive data visualization has sparked interest in exploring their suitability for visualizing software development data. Despite this, there is a lack of detailed investigation into the effectiveness of VR devices specifically for interacting with software development data visualizations.ObjectiveOur objective is to investigate the following question: “How do VR devices compare to traditional screens in visualizing data about software development?” Specifically, we aim to assess the accuracy of conclusions derived from exploring visualizations for understanding the software development process, as well as the time required to reach these conclusions.MethodIn our controlled experiment, we recruited N=32 volunteers with diverse backgrounds. Participants interacted with similar data visualizations in both VR and traditional screen environments. For the traditional screen setup, we utilized a commercially available set of interactive dashboards based on Kibana, commonly used by Bitergia customers for data insights. In the VR environment, we designed a set of visualizations, tailored to provide an equivalent dataset within a virtual room. Participants answered questions related to software evolution processes, specifically code review and issue tracking, in both VR and traditional screen environments, for two projects. We conducted statistical analyses to compare the correctness of their answers and the time taken for each question.ResultsOur findings indicate that the correctness of answers in both environments is comparable. Regarding time spent, we observed similar durations, except for complex questions that required examining multiple interconnected visualizations. In such cases, participants in the VR environment were able to answer questions more quickly.ConclusionBased on our results, we conclude that VR immersion can be equally effective as traditional screen setups for understanding software development processes through visualization of relevant metrics in most scenarios. Moreover, VR may offer advantages in comprehending complex tasks that require navigating through multiple interconnected visualizations. However, further experimentation is necessary to validate and reinforce these conclusions.

Recent studies on brain-computer interfaces (BCIs) based on the steady-state visual evoked potential (SSVEP) have demonstrated their use to control objects or generate commands in virtual reality (VR) environments. However, most SSVEP-based BCI studies performed in VR environments have adopted visual stimuli that are typically used in conventional LCD environments without considering the differences in the rendering devices (head-mounted displays (HMDs) used in the VR environments). The proximity between the visual stimuli and the eyes in HMDs can readily cause eyestrain, degrading the overall performance of SSVEP-based BCIs. Therefore, in the present study, we have tested two different types of visual stimuli—pattern-reversal checkerboard stimulus (PRCS) and grow/shrink stimulus (GSS)—on young healthy participants wearing HMDs. Preliminary experiments were conducted to investigate the visual comfort of each participant during the presentation of the visual stimuli. In subsequent online avatar control experiments, we observed considerable differences in the classification accuracy of individual participants based on the type of visual stimuli used to elicit SSVEP. Interestingly, there was a close relationship between the subjective visual comfort score and the online performance of the SSVEP-based BCI: most participants showed better classification accuracy under visual stimulus they were more comfortable with. Our experimental results suggest the importance of an appropriate visual stimulus to enhance the overall performance of the SSVEP-based BCIs in VR environments. In addition, it is expected that the appropriate visual stimulus for a certain user might be readily selected by surveying the user's visual comfort for different visual stimuli, without the need for the actual BCI experiments.

Background & Purpose: Perception of self-motion through VR provides a unique avenue to improve gait adaptation in chronic stroke survivors. Stroke subjects show deterioration in bilateral coordination during gait. Such asymmetrical gait patterns may benefit from training the lower limbs to walk under different task constraints for each leg. In this ongoing study, bilateral incoordination in gait was targeted with a split-belt paradigm and perception of self-motion was provided with a Virtual Reality (VR) environment. The VR environment was hypothesized to enhance the split-belt adaptation by removing conflict between the static visual input (as in normal treadmill walking) and the dynamic proprioceptive input. Subjects & Methods: Healthy young, healthy older adults and chronic stroke survivors walked on a split-belt treadmill in either a VR or a non-VR environment while being exposed to different belt speeds (fast: 1.5m/s and slow: 0.5m/s) for each leg. The VR stimuli consisted of walking in an infinitely long virtual corridor. Spatiotemporal measures as correlates of adaptation were compared between groups (young, old, stroke) and conditions (VR and non-VR). Results: The participants in the VR condition demonstrated an increase in stride length compared to the non-VR condition for both healthy young (P = .019) and healthy elderly (P = .014). Preliminary results from the stroke group showed a trend towards a more stable coordination pattern that was reached quicker in the VR group than the non-VR group. Conclusion: Results show that the perception of self-motion provided through VR may lead to faster and more enhanced adaptive capabilities. Such enhancement of adaptive capabilities during gait has important implications for pathological populations such as stroke survivors.

This paper includes a research review in five bibliographic databases on using the application of virtual reality (VR) and augmented reality (AR) in physical and occupational therapy (POT). This literature review addresses five research questions and two sub‐research questions. A total of 36 relevant studies were selected in the review based on the defined keywords and inclusion‐exclusion criteria. The primary motivation for using the application of VR and AR in POT is that it is accurate, involves higher patient participation, and requires less therapy recovery time. The standard software tool used is the Unity 3D game engine, and the common device used is the Oculus Rift HMD. Various applications of VR and AR consist of different VR environments and AR contents used in POT. Post‐stroke rehabilitation, rehabilitation exercises, pain management, mental and behavioral disorders, and autism in children are the main aspects addressed through the VR and AR environments. Literature review indicates that questionnaires, interviews, and observation are the primary metrics for measuring therapy's effectiveness. The study's findings show positive results such as reduced treatment time, nervousness, pain, hospitalization period, making therapy enjoyable and encouraging, improved quality of life, and focus on using the application of VR and AR in POT. This review will be relevant to researchers, VR and AR application designers, doctors, and patients using the application of VR and AR in POT. Further research addressing multiple participants with clinical trials, adding new VR environments and AR content in VR and AR applications, including follow‐up sessions, and increasing training sessions while using the application of VR and AR in POT are recommended.

The aim of this study was to evaluate the effects of mechanically stimulated sacculus on our height perception. Between 1.09.2022 and 30.06.2023, 52 volunteers, 27 women and 25 men, aged 20-50 years, were included in the study. Pure tone audiometry test, acoustic immittance, vestibular evoked myogenic potentials (VEMP) and mini mental tests (MMSE) were performed on these individuals. Afterwards, height estimations were made by looking from top to bottom and from bottom to top using mechanical stimulation in real environment and elevator simulation in virtual reality (VR) environment. Participants were informed in writing with an informed consent form and their signed consent was obtained. The averages of the height estimates made in the VR environment and in the real environment were compared with each other and no significant difference was observed (p > 0.05). When the height estimations made in the VR environment and in the real environment were compared with the current height value, a significant difference was observed only in the height estimation made by looking from the bottom up in the VR environment, and it was found to be higher than the current height (p < 0.05). When the height estimation values in the VR environment and in the real environment were compared with the place where height estimation was started, no significant difference was observed (p > 0.05). In our study, the effect of the mechanical effect of the saccule on the height perception was investigated, and no significant difference was obtained in the height estimates made in the VR environment and in the real environment. Mechanical stimulation of the saccule is thought to have a limited role in height perception.

Vision and Locomotion Combine to Drive Path Integration Sequences in Mouse Retrosplenial Cortex.

This study introduces AffectiVR, a dataset designed for periocular biometric authentication and emotion evaluation in virtual reality (VR) environments. To maximize immersion in VR environments, interactions must be seamless and natural, with unobtrusive authentication and emotion recognition technologies playing a crucial role. This study proposes a method for user authentication by utilizing periocular images captured by a camera attached to a VR headset. Existing datasets have lacked periocular images acquired in VR environments, limiting their practical application. To address this, periocular images were collected from 100 participants using the HTC Vive Pro and Pupil Labs infrared cameras in a VR environment. Participants also watched seven emotion-inducing videos, and emotional evaluations for each video were conducted. The final dataset comprises 1988 monocular videos and corresponding self-assessment manikin (SAM) evaluations for each experimental video. This study also presents a baseline study to evaluate the performance of biometric authentication using the collected dataset. A deep learning model was used to analyze the performance of biometric authentication based on periocular data collected in a VR environment, confirming the potential for implicit and continuous authentication. The high-resolution periocular images collected in this study provide valuable data not only for user authentication but also for emotion evaluation research. The dataset developed in this study can be used to enhance user immersion in VR environments and as a foundational resource for advancing emotion recognition and authentication technologies in fields such as education, therapy, and entertainment. This dataset offers new research opportunities for non-invasive continuous authentication and emotion recognition in VR environments, and it is expected to significantly contribute to the future development of related technologies.