Search Results (456)

Background: Port-a-catheter (PAC) placement is a common procedure in oncology that, despite local anaesthesia, can induce patient discomfort, procedural pain, and anxiety. Virtual reality hypnosis (VRH), combining immersive virtual reality with clinical hypnosis, has been proposed as a non-pharmacological adjunct to reduce peri-procedural distress. Objectives: This pilot study aimed to explore the suitability of VRH during PAC placement and its potential effects on pain, anxiety, and VRH-related experiences, while investigating psychological variables associated with VRH engagement. Methods: In this single-arm interventional monocentric prospective pilot study, twenty oncology patients undergoing first-time elective PAC placement received a VRH intervention delivered via a medical-grade head-mounted display throughout the procedure. Pain, anxiety, and VRH-related dimensions—including absorption, dissociation, automaticity, arousal, and sense of presence—were assessed pre- and post-procedure using self-reported numerical rating scales and questionnaires. Non-parametric Wilcoxon tests evaluated pre–post changes, and correlational analyses (Pearson’s and Spearman’s when necessary) explored associations between variables. Results: VRH was well tolerated by most participants, although three patients required additional pharmacological support, and four could not complete the session due to intolerance or technical issues. Anxiety scores decreased significantly following VRH, whereas pain showed a non-significant trend toward reduction. Post-procedural absorption and dissociation were positively associated with presence, and higher absorption traits were linked to greater immersive engagement and prior VR/hypnosis experience. Cybersickness was negatively associated with absorption. Older age was correlated with lower post-procedural pain, and females reported higher state anxiety. Conclusions: In this pilot, VRH was feasible, well tolerated, and associated with a significant exploratory reduction in procedural state anxiety. Given the single-arm design, these findings constitute directional evidence warranting controlled trial evaluation rather than proof of efficacy. These preliminary results support the rationale for randomised controlled trials to evaluate VRH efficacy, underlying mechanisms, and potential role as a non-pharmacological adjunct in oncology perioperative care. Full article

Virtual reality (VR) sickness induced by wearing a head-mounted display and viewing 360° videos has primarily been studied using subjective questionnaires administered before and after content viewing. However, this approach is limited to identifying the onset of sickness during content viewing. This study quantitatively addresses the association between objective measures (gaze direction, head pose, electrocardiogram, and optical flow) and VR sickness, adopting an exploratory approach. Real-time sickness during 360° video viewing was measured using the fast motion sickness scale, and overall sickness susceptibility was evaluated using the simulator sickness questionnaire. The results indicated that a higher VR sickness severity was associated with reduced gaze entropy and an increase in the magnitude and entropy of optical flow, suggesting its potential as an objective measure for real-time VR sickness assessment. Furthermore, in the comparison between susceptibility groups, the high-susceptibility group had a nominally significantly lower heart rate variability than the low-susceptibility group, indicating that physiological signals may serve as auxiliary tools for sensing the baseline of VR sickness. The optical flow reflects the visual stimuli of VR content independent of personal susceptibility, suggesting its potential as a content-driven indicator of VR sickness. Full article

Non-immersive (screen-based) virtual environments may offer a low-threshold way to elicit clinically relevant emotions while reducing barriers associated with immersive head-mounted displays. This study examined whether a non-immersive virtual scenario simulating a dirty public bathroom is associated with changes in disgust-related and anxiety-related responses in a non-clinical sample of university students, and explored links with obsessive–compulsive tendencies and contamination-related anxiety during the COVID-19 period. A total of 122 participants remotely explored the virtual environment. Before and after exposure, participants completed measures of state anxiety (EMAS-S) and disgust sensitivity (DSR); trait anxiety (EMAS-T), obsessive–compulsive symptoms (OCI-R), fear of COVID-19 (FCS), and engagement/activation during the experience were also assessed. Pre–post differences were tested using paired-sample t-tests, and associations among variables were examined via bivariate correlations. Results indicated a significant post-exposure increase in EMAS-S and DSR scores. Correlational analyses showed robust associations between disgust sensitivity and obsessive–compulsive symptoms, and between trait anxiety and fear of COVID-19. Gender and first-person videogame experience were related to subjective discomfort and activation, with higher levels reported by females and participants without gaming experience. The findings provide preliminary evidence that a remote, screen-based contamination scenario can elicit measurable disgust- and anxiety-related responses and that individual differences may shape subjective impact. However, because the study used a single-group pre–post design without a neutral VR condition or a non-VR control, causal conclusions about the effects of the virtual scenario cannot be drawn. Full article

Background: Addictive disorders are characterized by the dysregulation of neural circuits involved in reward processing, salience attribution, emotional regulation, and cognitive control. Traditional neuroimaging paradigms based on static or two-dimensional stimuli show limited ecological validity and may fail to capture the contextual complexity of real-world addictive triggers. Immersive virtual reality (VR) offers a novel approach to simulate realistic, multisensory environments capable of eliciting craving and emotional responses. Although several reviews have examined VR in addictive disorders, most combined immersive and non-immersive tools and did not restrict inclusion to studies with brain-based outcomes. Methods: This systematic review with narrative synthesis was conducted in PubMed/MEDLINE and APA PsycINFO for studies published up to 30 December 2025. This systematic review followed PRISMA 2020 and was prospectively registered in PROSPERO; due to heterogeneity, findings were synthesized narratively. Eligible studies included human participants with substance-related or behavioral addictions and employed immersive VR paradigms (e.g., head-mounted display–based environments) combined with neuroimaging or neurophysiological measures (EEG, fMRI, fNIRS, PET, or DTI). Risk of bias was assessed using ROB-2 or ROBINS-I, and overall certainty of evidence was evaluated with the GRADE framework. Results: Ten studies met the inclusion criteria, encompassing over 1450 participants with alcohol, nicotine, methamphetamine, opioid use disorders, and internet gaming disorder. Immersive VR was associated with craving-related neural responses across modalities, involving prefrontal, insular, limbic, and striatal networks. EEG studies reported spectral power changes associated with craving and attentional salience, while fMRI, fNIRS, and PET studies demonstrated activation and modulation of executive control and reward-related circuits. Preliminary longitudinal and interventional studies indicate that repeated VR exposure may induce neurobiological changes consistent with therapeutic modulation. Conclusions: Immersive VR combined with neuroimaging supports the use of immersive VR as an ecologically grounded framework to probe addiction-related brain circuits; however, larger trials and standardized reporting are needed to strengthen clinical translation. Future studies should prioritize adequately powered randomized designs, harmonized VR cue-reactivity paradigms, and transparent neuroimaging reporting to enable reproducibility and cumulative inference. Full article

As a next-generation immersive service, holographic video enables users to move freely within a virtual world. This imposes stringent requirements on wireless networks. Given the massive bandwidth capacity inherent to visible light, visible light communication (VLC) can effectively meet the transmission requirements of holographic video and is an ideal wireless technology for next-generation indoor immersive services. However, VLC channels are highly dependent on Line-of-Sight (LoS) links. Due to user mobility, traditional VLC systems relying on fixed-orientation Photodetectors (PDs) often suffer from severe channel fading, which significantly degrades the transmission performance. In this paper, we propose an indoor VLC holographic video transmission architecture supporting rotatable PDs, utilizing rotatable PDs mounted on Head-Mounted Displays (HMDs) to assist in holographic video transmission. To minimize the total transmission delay of all users, we address the holographic video transmission problem by jointly optimizing the transmit power allocation of VLC Access Points (APs) and the pitch and roll angles of the users’ PDs. By formulating the problem as a Markov Decision Process (MDP), we address it using a novel Deep Reinforcement Learning (DRL) strategy leveraging the Soft Actor–Critic (SAC) architecture. Simulation results demonstrate that the proposed scheme reduces the overall latency by up to 29.6% compared to the benchmark schemes. Furthermore, the convergence speed of the algorithm is improved by 35% compared to traditional deep reinforcement learning algorithms such as Deep Deterministic Policy Gradient (DDPG). Full article

To address the critical challenges of minimizing optical thickness and correcting chromatic aberrations in optically transparent head-mounted displays (HMDs), we propose a folded hybrid design incorporating freeform prisms and a discrete multi-wavelength achromatic metalens. Our approach integrates advanced optical engineering techniques to achieve optimal performance while maintaining compactness. The system leverages a phase-optimized SiNx/SiO₂ metalens combined with ray-tracing-based system optimization, enabling the development of a compact 12 mm thickness OST-HMD featuring an 8 mm exit pupil and a 39° virtual field of view (FOV). Through simulations, we demonstrate that this configuration achieves impressive modulation transfer function (MTF) values exceeding 0.7 at 50 lp/mm for see-through viewing and maintaining MTFs above 0.3 at 30 lp/mm for virtual imaging across wavebands. Simulation results highlight an improvement both in the miniaturization of the HMD while maintaining high resolution and in effective correction of chromatic aberrations, offering a robust solution for lightweight, high-performance AR display systems. This work represents an advancement in optically transparent display technology by providing an optimized design framework that balances compactness with visual fidelity. Full article

Background/Objectives: Dementia is a major global health challenge, with prevention strategies increasingly focusing on the preclinical stage of Subjective Cognitive Decline (SCD). This study aimed to evaluate the feasibility, usability, and acceptability of a 5-week immersive virtual reality and telemedicine-based multicomponent intervention, combining cognitive training with a health and lifestyle education program, in individuals with SCD. Methods: Thirty-nine individuals with SCD were randomly allocated to either the multi-component intervention (MC-I; n = 19) or the cognitive-only intervention (CO-I; n = 20). Both programs were delivered remotely via head-mounted displays and monitored through a telemedicine platform. Feasibility was assessed through retention, adherence, and safety measures. Post-intervention, participants completed the System Usability Scale (SUS), User Satisfaction Evaluation Questionnaire (USEQ), NASA Task Load Index (NASA-TLX), and Simulator Sickness Questionnaire (SSQ). Results: High feasibility was demonstrated by a 100% retention rate and 92% adherence. Both groups reported “excellent” usability (SUS mean: 84.04) and high satisfaction (USEQ mean: 26.7), with no significant differences between groups. The NASA-TLX reflected a moderate workload (mean: 56.1), characterized by high mental demand but low frustration. Safety was confirmed by remarkably low SSQ scores, indicating negligible cybersickness. Conclusions: The results provide strong preliminary evidence that a home-based, multi-component IVR intervention is safe, usable, and highly accepted by individuals with SCD. Integrating lifestyle education does not increase the perceived burden, supporting the scalability of this remote digital approach for dementia secondary prevention. Full article

Eye tracking in virtual reality (VR) head-mounted displays poses substantial engineering challenges, particularly under immersive display configurations with large fields of view (FOV), where optical layout, illumination, and image acquisition impose nontrivial system constraints. To address these design constraints, we present an integrated near-eye eye-tracking prototype tailored for immersive VR headsets, combining customized hardware components and a real-time software pipeline. The proposed system integrates optimized near-eye illumination and image acquisition with a pupil detection module and a deep learning-based gaze-vector estimation model, forming a real-time software pipeline for stable end-to-end gaze mapping under fixed calibration conditions. Under identical system settings, calibration procedures, and gaze-point mapping conditions, we evaluate the proposed gaze-vector estimation model through a controlled model-level ablation. The attention-enhanced model achieves an average angular deviation of 1.15°, corresponding to a 61.4% relative reduction compared with a baseline ResNet-152 model without attention. To demonstrate the usability of the system outputs at the application level, we further implement a real-time visualization example that integrates pupil diameter, gaze vectors, and blink events to depict the temporal evolution of eye-movement signals. This work provides a cost-effective and reproducible engineering reference for near-eye eye-movement acquisition and visualization in immersive VR settings and serves as a technical foundation for subsequent interaction design or behavioral analysis studies. Full article

Background: Post-Intensive Care Syndrome (PICS), comprising physical, cognitive, and psychological impairments, affects 50–75% of Intensive Care Unit (ICU) survivors and leads to long-term deficits. Virtual Reality (VR) has emerged as a tool to reduce ICU-related stress and support recovery, yet evidence remains fragmented and heterogeneous. Objective: To systematically review the safety, feasibility, and effects of immersive VR interventions targeting PICS-related outcomes in ICU and post-ICU populations, and to introduce a standardized taxonomy to classify and compare VR interventions in critical care contexts. Methods: This systematic review followed PRISMA 2020 guidelines and was registered in PROSPERO (CRD420251174623). Seven databases (Cochrane Library, PubMed, ScienceDirect, IEEE Xplore, ACM Digital Library, SpringerLink, and Scopus) were searched from inception to 2 August 2025. Eligible studies included ICU patients receiving immersive VR via head-mounted displays and targeting at least one PICS domain. Two reviewers independently screened studies and extracted data. Methodological quality was assessed using the Mixed Methods Appraisal Tool (MMAT, 2018). Due to substantial heterogeneity, findings were synthesized narratively. Results: Eleven studies were included. The most consistent effects concerned acute psychological outcomes, with 63.6% of studies reporting reduced anxiety or distress. Evidence for physical, cognitive, or long-term outcomes was limited and inconsistent, largely due to small samples, non-randomized designs, and brief intervention dosing. Conclusion: Current evidence supports VR as a feasible adjunct for acute psychological support in ICU settings. However, meaningful rehabilitation effects remain underexplored. The Five-Axis VR-PICS taxonomy clarifies intervention heterogeneity and provides a structured framework to guide rehabilitation-oriented VR research in critical care. Full article

Virtual reality (VR) is increasingly integrated into the rehabilitation of children with cerebral palsy (CP). However, evidence to substantiate its potential as part of standard care remains limited. This Phase 1 study aimed to evaluate a VR-based immersive gamification technology system (ImGTS) for use in CP rehabilitation based on its safety, acceptability, and usability in healthy children. The system included software and hardware designs informed by discussions with CP rehabilitation and VR development experts (e.g., developmental pediatricians, physical therapists) and tailored to the local context, tested with two setups: the head-mounted display (HMD) and the semi-cave automatic virtual environment (semi-CAVE). We describe the experience of 30 healthy children aged 6–12 years using the ImGTS (Mission to Planet Axel version 1.0) using either the HMD (n = 15) or semi-CAVE (n = 15) setup. Descriptive and thematic analyses of data from semi-structured interviews based on questionnaires for safety and acceptability, as well as observations of behaviors for the usability dimensions of effectiveness, efficiency, and satisfaction, indicated that participants were engaged and motivated with the ImGTS, with low incidence and severity of VR-related symptoms for both setups and high acceptance of the ImGTS, based on perceptions of the environment and feelings of presence. Usability was also high. These findings suggest that the ImGTS is safe, acceptable, and usable for healthy children. This trial provides initial evidence to guide the methods of subsequent trials testing the safety, acceptability, usability, and clinical effectiveness of the ImGTS in children with cerebral palsy, and, eventually, to guide its deployment. Full article

Background: Previous studies have demonstrated the benefits of virtual reality (VR) as an intervention tool guided by specialists. However, little is known about whether VR may pose risks in uncontrolled environments. Considering its implications for clinics and practice, this study aimed to assess the potential risks of a 3D VR simulation on postural control in young adults. Methods: Seventy-nine community-dwelling young adults completed a VR program using a head-mounted display that simulated a 3D roller-coaster ride while standing. Postural control was assessed using a force platform measuring frontal and lateral sway, center-of-pressure sway area, and frontal and lateral imbalance speed. The assessments were conducted with and without VR. Statistical analyses were performed using paired comparisons. Significance was set at 5%. Effect sizes (ESs) are reported. Results: Engaging in a VR roller-coaster simulation increased the participants’ imbalance in terms of frontal sway (p = 0.001; ES = 0.919), center-of-pressure sway area (p = 0.001; ES = 0.849), frontal imbalance speed (p = 0.001; ES = 0.910), and lateral imbalance speed (p = 0.001; ES = 0.663). No significant difference was observed in the lateral sway (p = 0.383). During VR exposure, 25% of the participants showed a clinically significant increase in postural instability. Despite having normal baseline parameters, participants with higher postural instability showed greater deterioration in postural control during VR exposure than those with lower postural instability. Conclusions: A 3D VR simulation affected several measures of postural control in community-dwelling young adults. Precautions should be taken when engaging in VR without appropriate specialist supervision. Full article

Background: Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, motor hyperactivity and verbal and cognitive impulsivity. Impairments in executive functions (EFs), in particular working memory, monitoring and organization of daily life, are frequently observed in children diagnosed with ADHD, and are reflected in behavioural, social-emotional and learning difficulties. The development and use of technologies such as virtual reality (VR), augmented reality (AR) and mixed reality (MR) for ADHD have increased in recent years, using a variety of tools to support including PC, video games, wearable devices and tangible interfaces. Objectives: To systematically map the current state of research on the use of AR, VR and MR technologies to assess and/or enhance EFs in children with ADHD. To evaluate the effects on their quality of life and on families’ and caregivers’ burden reduction. To explore the interventions’ clinical validity. Methods: A scoping review according to PRISMA-ScR guidelines was conducted. A systematic search was carried out in the Scopus and Web of Science databases for studies published between 2015 and 2025. Empirical studies published in English that examined children with ADHD aged <13 years were included. AR-, VR-, or MR-based interventions focused on EF were considered. For each study, the following features were recorded: year and country of publication, design, objectives, EFs considered, technology and hardware used, main results, and limitations. Results: Twenty studies were identified. The most frequently addressed functional domains were sustained and selective visual attention, working memory, and inhibition. Assessment interventions primarily involved the use of a head-mounted display (HMD) in conjunction with the Continuous Performance Test (CPT). Training interventions included immersive VR, serious video games, VR with motor or dual-task training, and MR. The results suggest that VR can enhance cognitive performance and sustained attention; however, longitudinal studies are required to evaluate its long-term effectiveness and integrate emotional skills. Conclusions: The use of these technologies is a promising strategy for the assessment and training of EFs in children with ADHD. These tools provide positive, inclusive feedback and motivating tasks. Nevertheless, larger sample studies and longitudinal follow-ups to confirm the suitability and effectiveness of the technology-based programs are warranted. Full article

Emerging technologies offer cultural institutions opportunities to expand their audiences and make their content more accessible. Augmented Virtuality (AV), which integrates real-world content into virtual environments, shows particular potential. It enables the transmission of live or pre-recorded stage performances, such as concerts and theater productions, from the stage to virtual audiences via increasingly affordable head-mounted displays (HMDs). However, as AV remains under-researched, little is known about which recording features enable an immersive user experience while maintaining cost-efficiency—an essential requirement for resource-constrained cultural institutions. In this context, we investigate the influence of features of audio and video recordings on key dimensions of user experience in the use case of a real opera performance integrated into a virtual opera house. We conducted a 2 × 2 within-subjects study with 30 participants to measure the effects of 2D versus 3D videos and stereophonic versus spatial audio rendering on several key dimensions of user experience. The results show that spatial audio has a positive impact on Place Illusion, whereas video dimensionality had no significant effect. Recommendations for the design of AV applications are derived from study results, aiming at balancing immersive user experience and cost-efficiency for virtual cultural participation. Full article

Visual information shapes spatial perception and body representation in human augmentation. However, the perceptual consequences of viewpoint-height changes produced by sensor–display geometry are not well understood. To address this gap, we developed an interface that maps a waist-mounted stereo fisheye camera to an eye-level viewpoint on a head-mounted display in real time. Geometric and timing calibration kept latency low enough to preserve a sense of agency and enable stable untethered walking. In a within-subject study comparing head- and waist-level viewpoints, participants approached adjustable gaps, rated passability confidence (1–7), and attempted passage when confident. We also recorded walking speed and assessed post-task body representation using a questionnaire. High gaps were judged passable and low gaps were not, irrespective of viewpoint. At the middle gap, confidence decreased with a head-level viewpoint and increased with a waist-level viewpoint, and walking speed decreased when a waist-level viewpoint was combined with a chest-height gap, consistent with added caution near the decision boundary. Body image reports most often indicated a lowered head position relative to the torso, consistent with visually driven rescaling rather than morphological change. These findings show that a waist-mounted interface for mobile viewpoint-height transformation can reliably shift spatial perception. Full article

A prominent application of Augmented Reality (AR) is to provide step-by-step guidance for procedural tasks as it allows information to be displayed in situ by overlaying it directly onto the user’s physical environment. While the potential of AR is well known, the perspectives and requirements of individuals with mental disabilities, who face both cognitive and psychological barriers at work, have yet to be addressed, particularly on Head-Mounted Displays (HMDs). To understand practical limitations of such a system, we conducted a mixed-methods user study with 29 participants, including individuals with mental disabilities, their colleagues, and support professionals. Participants used a commercially available system on an AR HMD to perform a machine setup task. Quantitative results revealed that participants with mental disabilities perceived the system as less usable than those without. Qualitative findings point towards actionable leverage points of improvement such as privacy-aware human support, motivating but lightweight gamification, user-controlled pacing with clear feedback, confidence-building interaction patterns, and clearer task intent of multimodal instructions. Full article