The impact of virtual reality and distractors on attentional processes: insights from EEG

Virtual reality (VR) allows to create controlled scenarios in which the quantity of stimuli can be modulated, as happen in real-life, where humans are subjected to various multisensory-often overlapping-stimuli. The present research aimed to study changes in attentional processes within an auditory oddball paradigm during a virtual exploration, while varying the amount of distractors. Twenty healthy volunteers underwent electroencephalography (EEG) during three different experimental conditions: an auditory oddball without VR (No-VR condition), an auditory oddball during VR exploration without distractors (VR-Empty condition), and an auditory oddball during VR exploration with a high level of distractors (VR-Full condition). Event-related potentials (ERPs) were computed averaging epochs of EEGs and analyzing peaks at 100 ms (N100) and 300 ms (P300) latencies. Results showed modulation of N100 amplitude in Fz and of P300 amplitude in Pz. Statistically significant differences in latency were observed only for P300 where the latency results delayed from the No-VR to VR-Full. The scalp topography revealed for P100 no significant differences between frequent and rare stimuli in either the No-VR and VR-Empty conditions. However, significant results were found in N100 in VR-Full condition. For P300, results showed differences between frequent and rare stimuli, in every condition. However, this difference is gradually less widespread from No-VR condition to the VR-Full. The emerging integration of VR with EEG may have important implications for studying brain attentional processing.

A comparative analysis of face and object perception in 2D laboratory and virtual reality settings: insights from induced oscillatory responses

In psychophysiological research, the use of Virtual Reality (VR) for stimulus presentation allows for the investigation of how perceptual processing adapts to varying degrees of realism. Previous time-domain studies have shown that perceptual processing involves modality-specific neural mechanisms, as evidenced by distinct stimulus-locked components. Analyzing induced oscillations across different frequency bands can provide further insights into neural processes that are not strictly phase-locked to stimulus onset. This study uses a simple perceptual paradigm presenting images of faces and cars on both a standard 2D monitor and in an immersive VR environment. To investigate potential modality-dependent differences in attention, cognitive load, and task-related post-movement processing, the induced alpha, theta and beta band responses are compared between the two modalities. No evidence was found for differences in stimulus-dependent attention or task-related post-movement processing between the 2D conditions and the realistic virtual conditions in electrode space, as posterior alpha suppression and re-synchronization of centro-parietal beta did not differ between conditions. However, source analysis revealed differences in the attention networks engaged during 2D and 3D perception. Midfrontal theta was significantly stronger in laboratory conditions, indicating higher cognitive load than in the VR environment. Exploratory analysis of posterior theta showed stronger responses in VR, possibly reflecting the processing of depth information provided only by the 3D material. In addition, the theta response seems to be generated by distinct neuronal sources under realistic virtual conditions indicating enhanced involvement of semantic information processing and social cognition.

Current opportunities and challenges of immersive virtual reality for psychological research and application

Immersive virtual reality (iVR), that is, digital stereoscopic 360° scenarios usually presented in head-mounted displays, has gained much popularity in medical, educational, and consumer contexts in the last years. Recently, psychological research started to utilize the theoretical and methodological advantages of iVR. Furthermore, understanding cognitive, emotional, and behavioral processes in iVR similar to real-life is a genuinely psychological, currently understudied topic. This article briefly reviews the current application of iVR in psychological research and related disciplines. The review presents empirical evidence for opportunities and strengths (e.g., realism, experimental control, effectiveness of therapeutic and educational interventions) as well as challenges and weaknesses (e.g., differences in experiencing presence, interacting with VR content including avatars, i.e., graphical representation of a person). The main part discusses areas requiring additional basic research, such as cognitive processes, socio-emotional processes during social interactions in iVR, and possible societal implications (e.g., fraud, VR-addiction). For both research and application, iVR offers a contemporary extension of the psychological toolkit, offering new avenues to investigate and enhance core phenomena of psychology such as cognition, affect, motivation, and behavior. Still, it is crucial to exercise caution in its application as excessive and careless use of iVR can pose risks to individuals' mental and physical well-being.

Expanding the empirical study of virtual reality beyond empathy to compassion, moral reasoning, and moral foundations

This study utilizes a controlled experimental design to investigate the influence of a virtual reality experience on empathy, compassion, moral reasoning, and moral foundations. With continued debate and mixed results from previous studies attempting to show relationships between virtual reality and empathy, this study takes advantage of the technology for its ability to provide a consistent, repeatable experience, broadening the scope of analysis beyond empathy. A systematic literature review identified the most widely used and validated moral psychology assessments for the constructs, and these assessments were administered before and after the virtual reality experience. The study is comprised of two pre-post experiments with student participants from a university in the United States. The first experiment investigated change in empathy and moral foundations among 44 participants, and the second investigated change in compassion and moral reasoning among 69 participants. The results showed no significant change in empathy nor compassion, but significant change in moral reasoning from personal interest to post-conventional stages, and significant increase in the Care/harm factor of moral foundations. By testing four of the primary constructs of moral psychology with the most widely used and validated assessments in controlled experiments, this study attempts to advance our understanding of virtual reality and its potential to influence human morality. It also raises questions about our self-reported assessment tools and provides possible new insights for the constructs examined.

Electrophysiological correlates of face and object perception: A comparative analysis of 2D laboratory and virtual reality conditions

Human face perception is a specialized visual process with inherent social significance. The neural mechanisms reflecting this intricate cognitive process have evolved in spatially complex and emotionally rich environments. Previous research using VR to transfer an established face perception paradigm to realistic conditions has shown that the functional properties of face-sensitive neural correlates typically observed in the laboratory are attenuated outside the original modality. The present study builds on these results by comparing the perception of persons and objects under conventional laboratory (PC) and realistic conditions in VR. Adhering to established paradigms, the PC- and VR modalities both featured images of persons and cars alongside standard control images. To investigate the individual stages of realistic face processing, response times, the typical face-sensitive N170 component, and relevant subsequent components (L1, L2; pre-, post-response) were analyzed within and between modalities. The between-modality comparison of response times and component latencies revealed generally faster processing under realistic conditions. However, the obtained N170 latency and amplitude differences showed reduced discriminative capacity under realistic conditions during this early stage. These findings suggest that the effects commonly observed in the lab are specific to monitor-based presentations. Analyses of later and response-locked components showed specific neural mechanisms for identification and evaluation are employed when perceiving the stimuli under realistic conditions, reflected in discernible amplitude differences in response to faces and objects beyond the basic perceptual features. Conversely, the results do not provide evidence for comparable stimulus-specific perceptual processing pathways when viewing pictures of the stimuli under conventional laboratory conditions.

Autism spectrum disorder: pathogenesis, biomarker, and intervention therapy

Autism spectrum disorder (ASD) has become a common neurodevelopmental disorder. The heterogeneity of ASD poses great challenges for its research and clinical translation. On the basis of reviewing the heterogeneity of ASD, this review systematically summarized the current status and progress of pathogenesis, diagnostic markers, and interventions for ASD. We provided an overview of the ASD molecular mechanisms identified by multi-omics studies and convergent mechanism in different genetic backgrounds. The comorbidities, mechanisms associated with important physiological and metabolic abnormalities (i.e., inflammation, immunity, oxidative stress, and mitochondrial dysfunction), and gut microbial disorder in ASD were reviewed. The non-targeted omics and targeting studies of diagnostic markers for ASD were also reviewed. Moreover, we summarized the progress and methods of behavioral and educational interventions, intervention methods related to technological devices, and research on medical interventions and potential drug targets. This review highlighted the application of high-throughput omics methods in ASD research and emphasized the importance of seeking homogeneity from heterogeneity and exploring the convergence of disease mechanisms, biomarkers, and intervention approaches, and proposes that taking into account individuality and commonality may be the key to achieve accurate diagnosis and treatment of ASD.

Serious Games for Developing Social Skills in Children and Adolescents with Autism Spectrum Disorder: A Systematic Review

Serious games represent a promising avenue for intervention with children diagnosed with autism spectrum disorder, a neurodevelopmental disorder marked by persistent challenges in social communication and the presence of restricted, repetitive behaviors. Despite this potential, comprehensive reviews on this subject are scarce. This systematic review aims to evaluate the effectiveness of serious games and their specific characteristics in enhancing social skills among children and adolescents with autism. Employing PICO strategies and adhering to PRISMA guidelines, we screened 149 studies initially identified through PubMed and EBSCOhost databases. Nine studies met inclusion criteria and found a positive influence of serious games on social skills and related domains, encompassing emotion recognition/encoding/decoding, emotional regulation, eye gaze, joint attention, and behavioral skills. Nevertheless, despite these promising results, the limited available evidence underscores the need for rigorous study designs to consolidate findings and integrate evidence-based intervention strategies.

Moral conformity in a digital world: Human and nonhuman agents as a source of social pressure for judgments of moral character

Could judgments about others' moral character be changed under group pressure produced by human and virtual agents? In Study 1 (N = 103), participants first judged targets' moral character privately and two weeks later in the presence of real humans. Analysis of how many times participants changed their private moral judgments under group pressure showed that moral conformity occurred, on average, 43% of the time. In Study 2 (N = 138), we extended this using Virtual Reality, where group pressure was produced either by avatars allegedly controlled by humans or AI. While replicating the effect of moral conformity (at 28% of the time), we find that the moral conformity for the human and AI-controlled avatars did not differ. Our results suggest that human and nonhuman groups shape moral character judgments in both the physical and virtual worlds, shedding new light on the potential social consequences of moral conformity in the modern digital world.

Co-Design of a Virtual Reality Multiplayer Adventure Game for Adolescents With Autism Spectrum Disorder: Mixed Methods Study

BACKGROUND

Virtual reality (VR) adventure games can offer ideal technological solutions for training social skills in adolescents with autism spectrum disorder (ASD), leveraging their support for multisensory and multiplayer interactions over distance, which may lower barriers to training access and increase user motivation. However, the design of VR-based game environments for social skills training is still understudied and deserves the deployment of an inclusive design approach to ensure its acceptability by target users.

OBJECTIVE

We aimed to present the inclusive design process that we had followed to develop the Zentastic VR adventure game to foster social skills training in adolescents with ASD and to investigate its feasibility as a training environment for adolescents.

METHODS

The VR game supports multiplayer training sessions involving small groups of adolescents and their therapists, who act as facilitators. Adolescents with ASD and their therapists were involved in the design and in an explorative acceptability study of an initial prototype of the gaming environment, as well as in a later feasibility multisession evaluation of the VR game final release.

RESULTS

The feasibility study demonstrated good acceptability of the VR game by adolescents and an enhancement of their social skills from baseline to posttraining.

CONCLUSIONS

The findings provide preliminary evidence of the benefits that VR-based games can bring to the training of adolescents with ASD and, potentially, other neurodevelopmental disorders.

Examining the exposure-reception-retention link in realistic communication environments via VR and eye-tracking: The VR billboard paradigm

Exposure is key to message effects. No effects can ensue if a health, political, or commercial message is not noticed. Yet, existing research in communication, advertising, and related disciplines often measures 'opportunities for exposure' at an aggregate level, whereas knowing whether recipients were 'actually exposed' to a message requires a micro-level approach. Micro-level research, on the other hand, focuses on message processing and retention, takes place under highly controlled laboratory conditions with forced message exposure, and largely ignores how recipients attend selectively to messages under more natural conditions. Eye-tracking enables us to assess actual exposure, but its previous applications were restricted to screen-based reading paradigms lacking ecological validity or field studies that suffer from limited experimental control. Our solution is to measure eye-tracking within an immersive VR environment that creates the message delivery and reception context. Specifically, we simulate a car ride down a highway alongside which billboards are placed. The VR headset (HP Omnicept Pro) provides an interactive 3D view of the environment and holds a seamlessly integrated binocular eye tracker that records the drivers' gaze and detects all fixations on the billboards. This allows us to quantify the nexus between exposure and reception rigorously, and to link our measures to subsequent memory, i.e., whether messages were remembered, forgotten, or not even encoded. An empirical study shows that incidental memory for messages differs based on participants' gaze behavior while passing the billboards. The study further shows how an experimental manipulation of attentional demands directly impacts drivers' gaze behavior and memory. We discuss the large potential of this paradigm to quantify exposure and message reception in realistic communication environments and the equally promising applications in new media contexts (e.g., the Metaverse).

Emotion expression and cooperation under collective risks

The difficulties associated with solving Humanity's major global challenges have increasingly led world leaders and everyday citizens to publicly adopt strong emotional responses, with either mixed or unknown impacts on others' actions. Here, we present two experiments showing that non-verbal emotional expressions in group interactions play a critical role in determining how individuals behave when contributing to public goods entailing future and uncertain returns. Participants' investments were not only shaped by emotional expressions but also enhanced by anger when compared with joy. Our results suggest that global coordination may benefit from interaction in which emotion expressions can be paramount.

Visual Facial Enhancements Can Significantly Improve Speech Perception in the Presence of Noise

Human speech perception is generally optimal in quiet environments, however it becomes more difficult and error prone in the presence of noise, such as other humans speaking nearby or ambient noise. In such situations, human speech perception is improved by speech reading, i.e., watching the movements of a speaker's mouth and face, either consciously as done by people with hearing loss or subconsciously by other humans. While previous work focused largely on speech perception of two-dimensional videos of faces, there is a gap in the research field focusing on facial features as seen in head-mounted displays, including the impacts of display resolution, and the effectiveness of visually enhancing a virtual human face on speech perception in the presence of noise. In this paper, we present a comparative user study ( N=21) in which we investigated an audio-only condition compared to two levels of head-mounted display resolution ( 1832×1920 or 916×960 pixels per eye) and two levels of the native or visually enhanced appearance of a virtual human, the latter consisting of an up-scaled facial representation and simulated lipstick (lip coloring) added to increase contrast. To understand effects on speech perception in noise, we measured participants' speech reception thresholds (SRTs) for each audio-visual stimulus condition. These thresholds indicate the decibel levels of the speech signal that are necessary for a listener to receive the speech correctly 50% of the time. First, we show that the display resolution significantly affected participants' ability to perceive the speech signal in noise, which has practical implications for the field, especially in social virtual environments. Second, we show that our visual enhancement method was able to compensate for limited display resolution and was generally preferred by participants. Specifically, our participants indicated that they benefited from the head scaling more than the added facial contrast from the simulated lipstick. We discuss relationships, implications, and guidelines for applications that aim to leverage such enhancements.

Keeping track of reality: embedding visual memory in natural behaviour

Since immersive virtual reality (IVR) emerged as a research method in the 1980s, the focus has been on the similarities between IVR and actual reality. In this vein, it has been suggested that IVR methodology might fill the gap between laboratory studies and real life. IVR allows for high internal validity (i.e., a high degree of experimental control and experimental replicability), as well as high external validity by letting participants engage with the environment in an almost natural manner. Despite internal validity being crucial to experimental designs, external validity also matters in terms of the generalizability of results. In this paper, we first highlight and summarise the similarities and differences between IVR, desktop situations (both non-immersive VR and computer experiments), and reality. In the second step, we propose that IVR is a promising tool for visual memory research in terms of investigating the representation of visual information embedded in natural behaviour. We encourage researchers to carry out experiments on both two-dimensional computer screens and in immersive virtual environments to investigate visual memory and validate and replicate the findings. IVR is valuable because of its potential to improve theoretical understanding and increase the psychological relevance of the findings.

The Interplay Between Human Likeness and Agency on Virtual Influencer Credibility

This study investigated how human likeness (human-like vs. avatar-like) and agency (avatar vs. agent) interact to determine source credibility and the intention to interact with virtual influencers. The results revealed that human likeness significantly influenced three types of source credibility (attractiveness, trustworthiness, and expertise) and interaction intention. However, the agency of virtual influencers did not have a significant impact. Notably, the automated virtual influencer (i.e., the agent condition) was perceived to be more attractive and trustworthy and elicited higher interaction intention than the influencer operated by a human (i.e., the avatar condition). However, this relationship was observed only in the avatar-like condition. Thus, agency moderated the indirect relationship between human likeness and interaction through attractiveness and trustworthiness. Finally, the theoretical and practical implications of the findings and ideas for future research are discussed.

Investigating social comparison behaviour in an immersive virtual reality classroom based on eye-movement data

Higher-achieving peers have repeatedly been found to negatively impact students' evaluations of their own academic abilities (i.e., Big-Fish-Little-Pond Effect). Building on social comparison theory, this pattern is assumed to result from students comparing themselves to their classmates; however, based on existing research designs, it remains unclear how exactly students make use of social comparison information in the classroom. To determine the extent to which students (N = 353 sixth graders) actively attend and respond to social comparison information in the form of peers' achievement-related behaviour, we used eye-tracking data from an immersive virtual reality (IVR) classroom. IVR classrooms offer unprecedented opportunities for psychological classroom research as they allow to integrate authentic classroom scenarios with maximum experimental control. In the present study, we experimentally varied virtual classmates' achievement-related behaviour (i.e., their hand-raising in response to the teacher's questions) during instruction, and students' eye and gaze data showed that they actively processed this social comparison information. Students who attended more to social comparison information (as indicated by more frequent and longer gaze durations at peer learners) had less favourable self-evaluations. We discuss implications for the future use of IVR environments to study behaviours in the classroom and beyond.

Exploring the Darkverse: A Multi-Perspective Analysis of the Negative Societal Impacts of the Metaverse

The Metaverse has the potential to form the next pervasive computing archetype that can transform many aspects of work and life at a societal level. Despite the many forecasted benefits from the metaverse, its negative outcomes have remained relatively unexplored with the majority of views grounded on logical thoughts derived from prior data points linked with similar technologies, somewhat lacking academic and expert perspective. This study responds to the dark side perspectives through informed and multifaceted narratives provided by invited leading academics and experts from diverse disciplinary backgrounds. The metaverse dark side perspectives covered include: technological and consumer vulnerability, privacy, and diminished reality, human-computer interface, identity theft, invasive advertising, misinformation, propaganda, phishing, financial crimes, terrorist activities, abuse, pornography, social inclusion, mental health, sexual harassment and metaverse-triggered unintended consequences. The paper concludes with a synthesis of common themes, formulating propositions, and presenting implications for practice and policy.

The promise and peril of interactive embodied agents for studying non-verbal communication: a machine learning perspective

In face-to-face interactions, parties rapidly react and adapt to each other's words, movements and expressions. Any science of face-to-face interaction must develop approaches to hypothesize and rigorously test mechanisms that explain such interdependent behaviour. Yet conventional experimental designs often sacrifice interactivity to establish experimental control. Interactive virtual and robotic agents have been offered as a way to study true interactivity while enforcing a measure of experimental control by allowing participants to interact with realistic but carefully controlled partners. But as researchers increasingly turn to machine learning to add realism to such agents, they may unintentionally distort the very interactivity they seek to illuminate, particularly when investigating the role of non-verbal signals such as emotion or active-listening behaviours. Here I discuss some of the methodological challenges that may arise when machine learning is used to model the behaviour of interaction partners. By articulating and explicitly considering these commitments, researchers can transform 'unintentional distortions' into valuable methodological tools that yield new insights and better contextualize existing experimental findings that rely on learning technology. This article is part of a discussion meeting issue 'Face2face: advancing the science of social interaction'.

Real-life relevant face perception is not captured by the N170 but reflected in later potentials: A comparison of 2D and virtual reality stimuli

The perception of faces is one of the most specialized visual processes in the human brain and has been investigated by means of the early event-related potential component N170. However, face perception has mostly been studied in the conventional laboratory, i.e., monitor setups, offering rather distal presentation of faces as planar 2D-images. Increasing spatial proximity through Virtual Reality (VR) allows to present 3D, real-life-sized persons at personal distance to participants, thus creating a feeling of social involvement and adding a self-relevant value to the presented faces. The present study compared the perception of persons under conventional laboratory conditions (PC) with realistic conditions in VR. Paralleling standard designs, pictures of unknown persons and standard control images were presented in a PC- and a VR-modality. To investigate how the mechanisms of face perception differ under realistic conditions from those under conventional laboratory conditions, the typical face-specific N170 and subsequent components were analyzed in both modalities. Consistent with previous laboratory research, the N170 lost discriminatory power when translated to realistic conditions, as it only discriminated faces and controls under laboratory conditions. Most interestingly, analysis of the later component [230–420 ms] revealed more differentiated face-specific processing in VR, as indicated by distinctive, stimulus-specific topographies. Complemented by source analysis, the results on later latencies show that face-specific neural mechanisms are applied only under realistic conditions (A video abstract is available in the Supplementary material and via YouTube: https://youtu.be/TF8wiPUrpSY).

On the Evaluation of Engagement in Immersive Applications When Users Are on the Autism Spectrum

New generation wearable devices allow for the development of interactive environments tailored for Virtual Reality (VR)- and Augmented Reality (AR)-based treatment of Autism Spectrum Disorders (ASD). Experts agree on their potential; however, there is lack of consensus on how to perform trials and the need arises for evaluation frameworks, methods, and techniques appropriate for the ASD population. In this paper, we report on a study conducted with high-functioning ASD people in the 21-23 age range, with the objectives of (1) evaluating the engagement of two headsets offering distinct immersive experiences, (2) reasoning on the interpretation of engagement factors in the case of ASD people, and (3) translating results into general guidelines for the development of VR/AR-based ASD treatment. To this aim, we (1) designed two engagement evaluation frameworks based on behavioral observation measures, (2) set up two packages of reference immersive scenarios, (3) defined the association between metrics and scenarios, and (4) administered the scenarios in distinct sessions for the investigated headsets. Results show that the immersive experiences are engaging and that the apparent lack of success of some evaluation factors can become potential advantages within the framework of VR/AR-based ASD treatment design.

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.

Interaction with Virtual Humans and Effect of Emotional Expressions: Anger Matters!

Today we are experiencing a hybrid real-virtual society in which the interaction with virtual humans is normal and "quasi-social". Understanding the way we react to the interaction with virtual agents and the impact of emotions on social dynamics in the virtual world is fundamental. Therefore, in this study we investigated the implicit effect of emotional information by adopting a perceptual discrimination task. Specifically, we devised a task that explicitly required perceptual discrimination of a target while involving distance regulation in the presence of happy, neutral, or angry virtual agents. In two Immersive Virtual Reality experiments, participants were instructed to discriminate a target on the virtual agents' t-shirts, and they had to provide the response by stopping the virtual agents (or themselves) at the distance where they could identify the target. Thus, facial expressions were completely irrelevant to the perceptual task. The results showed that the perceptual discrimination implied a longer response time when t-shirts were worn by angry rather than happy or neutral virtual agents. This suggests that angry faces interfered with the explicit perceptual task people had to perform. From a theoretical standpoint, this anger-superiority effect could reflect an ancestral fear/avoidance mechanism that prompts automatic defensive reactions and bypasses other cognitive processes.

Effects of immersion in a simulated natural environment on stress reduction and emotional arousal: A systematic review and meta-analysis

Background

Although the mental health benefits of exposure to simulated natural environments are well established by researchers from environmental psychology, landscape architecture, and public health, it is unclear whether and to what extent technological immersion affects these benefits.

Methods

Systematical literature searches were conducted in May 2022 from six databases. The risk of bias was evaluated using the Cochrane's Risk of Bias tool 2.0 and the Risk of Bias in Non-randomized Studies of Interventions tool. We performed a random-effects meta-regression to investigate the heterogeneity. The immersion levels of included studies were classified by projection devices and motion capture, and then subgroup analysis was conducted.

Results

Twenty-six publications were included. Exposure to simulated nature was confirmed to be associated with increased positive affect 0.40 [95% confidence interval (CI): 0.22, 0.58], vigor 0.58 (95% CI: 0.30, 0.86), calmness 0.54 (95% CI: 0.17, 0.92) and decreased perceived stress -0.38 (95% CI: -0.71, -0.06), total mood disturbance -0.87 (95% CI: -1.17, -0.57), tension -0.70 (95% CI: -0.99, -0.41), fatigue -0.60 (95% CI: -0.91, -0.28), anxiety -0.72 (95% CI: -1.43, -0.02), depression -0.33 (95% CI: -0.52, -0.14), confusion -0.79 (95% CI: -1.19, -0.40), and anger -0.54 (95% CI: -0.76, -0.31). Gender, health status, study design, mean age, and single exposure duration were not significant when entered in a meta-regression. For positive affect, medium immersion was observed to produce a larger effect than low and high immersion. All included studies had a moderate to high risk of bias.

Conclusion

Audio-visual exposure to simulated nature contributes to stress relief and emotional arousal. The immersion level explains the heterogeneity of positive affect triggered by simulated nature. Focusing on the technical features will open up new possibilities for combining actual and simulated nature's mental health benefits.

Cognition, criminal conduct, and virtual reality: Understanding and reducing offending using simulated environments

Over the past years, research has shown that virtual reality (VR) technology can be used to observe, interpret, and change human behavior and cognition in a variety of domains. This chapter explores the potential of VR as a tool to observe, interpret, and change human behavior and cognition as they relate to antisocial behavior. We review the criminological research literature as well as research literature from related disciplines on VR applications that has focused on observing and reducing antisocial behavior. The main findings of our review suggest that the key merits of VR in the domain of crime and antisocial behavior are its ability to provide safe learning environments that would otherwise involve risk, the possibility of generating ethical and ecologically valid virtual alternatives for real-life situations, and the development of stimuli that are impossible to create in real life. These unique characteristics make VR a promising tool to observe criminal behavior as it takes place and develop intervention programs to reduce antisocial behavior.

Global urban homogenization and the loss of emotions

Urban expansion is generating unprecedented homogenization of landscapes across the world. This uniformization of urban forms brings along dramatic environmental, social, and health problems. Reverting such processes requires activating people's sense of place, their feeling of caring for their surroundings, and their community engagement. While emotions are known to have a modulating effect on behavior, their role in urban transformation is unknown. Drawing on large cognitive-psychological experiments in two countries, we demonstrate for the first time that urban homogenization processes lower people's affective bounds to places and ultimately their intentions to engage with their neighbourhoods. The dulled emotional responses in peri-urban areas compared to urban and rural areas can be explained by lower social cohesion and place attachment. The findings highlight the significance of considering emotions in shaping just, equitable, sustainable, and resilient cities.

Avatar led interventions in the Metaverse reveal that interpersonal effectiveness can be measured, predicted, and improved

Experiential learning has been known to be an engaging and effective modality for personal and professional development. The Metaverse provides ample opportunities for the creation of environments in which such experiential learning can occur. In this work, we introduce a novel interpersonal effectiveness improvement framework (ELAINE) that combines Artificial Intelligence and Virtual Reality to create a highly immersive and efficient learning experience using avatars. We present findings from a study that uses this framework to measure and improve the interpersonal effectiveness of individuals interacting with an avatar. Results reveal that individuals with deficits in their interpersonal effectiveness show a significant improvement (p < 0.02) after multiple interactions with an avatar. The results also reveal that individuals interact naturally with avatars within this framework, and exhibit similar behavioral traits as they would in the real world. We use this as a basis to analyze the underlying audio and video data streams of individuals during these interactions. We extract relevant features from these data and present a machine-learning based approach to predict interpersonal effectiveness during human-avatar conversation. We conclude by discussing the implications of these findings to build beneficial applications for the real world.

Distressed (Type D) personality is predicted by avoidance: evidence from a computer-based avatar task

Background

One personality type associated with poor health outcomes is distressed (Type D) personality which involves high levels of both social inhibition (SI) and negative affectivity (NA). Type D is also linked to psychopathologies such as post-traumatic stress disorder (PTSD), anxiety disorders, and depression. One mechanism through which personality temperament may result in these psychopathologies is avoidance. Recently, a computer-based measure designed to assess avoidant behaviors, in which the participant guides the behavior of an avatar interacting with strangers in social situations, has been found to be related to various forms of avoidance. In the current study, we extended this work with the avatar avoidance task to determine its relationship to distressed (Type D) personality. We hypothesized that Type D personality, along with SI, but not NA, would be positively related to avatar avoidance scores. We also hypothesized that avatar avoidance scores would be higher in Type D individuals than non-Type D individuals.

Methods

A total of 302 undergraduates completed the Distressed Type D Personality Scale (DS-14), and a computer-based avatar avoidance task.

Results

Type D and SI, and NA to a lesser degree, were positively correlated with avoidance scores on the avatar task. Furthermore, regression analyses revealed that Type D and SI scores were best predicted by a model including avoidance scores and education level while NA scores were best predicted by a model including avoidance scores. Standard cut-off scores on the DS-14 scale resulted in four groups (i.e., low SI and NA, high SI, high NA, and Type D) which significantly differed in avoidance scores. Specifically, Type D individuals had higher avoidance scores than the other three groups. Taken together these findings support a role for avoidance in Type D personality. The computer-based avatar avoidance task may be particularly relevant as an ecologically valid measure to identify avoidance in a virtual setting for use with individuals expressing Type D personality who may be unwilling or unable to accurately self-report or describe their own avoidant tendencies.

Effect of Social Actors Perceived Agency on Social Presence in Computer-Mediated Communication

Nowadays, both text-based and 3D online applications rely on conversational agents and autonomous characters to interact with users. Previous experiments demonstrated that perceived agency, that is to say, one’s belief in interacting with a computer- or another human-controlled entity could impact social interaction. At present, theories and results still diverge and no consensus has been reached. Therefore, we developed an experiment to investigate the effect of perceived agency and emotional communication on social presence. Participants were told that they would play an online image recognition game against a computer- or a human-controlled opponent. In both cases, participants faced a computer-controlled opponent designed to provide a challenging yet balanced competitive experience. Depending on the experimental conditions, participants were able to communicate with their opponents using emoticons between the game rounds. Results demonstrate a significant main effect of emotional communication on the three dimensions of social presence we considered in this experiment. An interaction effect between perceived agency and emotional communication was observed in copresence, another core dimension of social presence. The impact of emotional communication on participants’ sense of copresence depends on the perceived agency of the opponent. A significant increase was observed for participants facing a computer-controlled opponent when emotional communication was allowed. The sense of copresence was even higher when they were facing a computer-controlled opponent rather than a presumed human-controlled one. These results are discussed with regard to theories of social interaction in computer-mediated communication.

Data science for pedestrian and high street retailing as a framework for advancing urban informatics to individual scales

Background

In this paper, we consider the applicability of the customer journey framework from retailing as a driver for urban informatics at individual scales within urban science. The customer journey considers shopper experiences in the context of shopping paths, retail service spaces, and touch-points that draw them into contact. Around this framework, retailers have developed sophisticated data science for observation, identification, and measurement of customers in the context of their shopping behavior. This knowledge supports broad data-driven understanding of customer experiences in physical spaces, economic spaces of decision and choice, persuasive spaces of advertising and branding, and inter-personal spaces of customer-staff interaction.

Method

We review the literature on pedestrian and high street retailing, and on urban informatics. We investigate whether the customer journey could be usefully repurposed for urban applications. Specifically, we explore the potential use of the customer journey framework for producing new insight into pedestrian behavior, where a sort of empirical hyperopia has long abounded because data are always in short supply.

Results

Our review addresses how the customer journey might be used as a structure for examining how urban walkers come into contact with the built environment, how people actively and passively sense and perceive ambient city life as they move, how pedestrians make sense of urban context, and how they use this knowledge to build cognition of city streetscapes. Each of these topics has relevance to walking studies specifically, but also to urban science more generally. We consider how retailing might reciprocally benefit from urban science perspectives, especially in extending the reach of retailers' insight beyond store walls, into the retail high streets from which they draw custom.

Conclusion

We conclude that a broad set of theoretical frameworks, data collection schemes, and analytical methodologies that have advanced retail data science closer and closer to individual-level acumen might be usefully applied to accomplish the same in urban informatics. However, we caution that differences between retailers' and urban scientists' viewpoints on privacy presents potential controversy.

Ecological Validity, External Validity, and Mundane Realism in Hearing Science

Tests of hearing function are typically conducted in conditions very different from those in which people need to hear and communicate. Even when test conditions are more similar, they cannot represent the diversity of situations that may be encountered by individuals in daily life. As a consequence, it is necessary to consider external validity: the extent to which findings are likely to generalize to conditions beyond those in which data are collected. External validity has long been a concern in many fields and has led to the development of theories and methods aimed at improving generalizability of laboratory findings. Within hearing science, along with related fields, efforts to address generalizability have come to focus heavily on realism: the extent to which laboratory conditions are similar to conditions found in everyday settings of interest. In fact, it seems that realism is now tacitly equated with generalizability. The term that has recently been applied to this approach by many researchers is ecological validity . Recent usage of the term ecological validity within hearing science, as well as other fields, is problematic for three related reasons: (i) it encourages the conflation of the separate concepts of realism and validity; (ii) it diverts attention from the need for methods of quantifying generalization directly; and (iii) it masks a useful longstanding definition of ecological validity within the field of ecological psychology. The definition of ecological validity first used within ecological psychology-the correlation between cues received at the peripheral nervous system and the identity of distant objects or events in the environment-is entirely different from its current usage in hearing science and many related fields. However, as part of an experimental approach known as representative design , the original concept of ecological validity can play a valuable role in facilitating generalizability. This paper will argue that separate existing terms should be used when referring to realism and generalizability, and that the definition of ecological validity provided by the Lens Model may be a valuable conceptual tool within hearing science.

A novel immersive virtual reality environment for the motor rehabilitation of stroke patients: A feasibility study

We designed and implemented an immersive virtual reality (VR) environment for upper limb rehabilitation, which possesses several notable features. First, by exploiting modern computer graphics its can present a variety of scenarios that make the rehabilitation routines challenging yet enjoyable for patients, thus enhancing their adherence to the therapy. Second, immersion in a virtual 3D space allows the patients to execute tasks that are closely related to everyday gestures, thus enhancing the transfer of the acquired motor skills to real-life routines. Third, in addition to the VR environment, we also developed a client app running on a PC that allows to monitor in real-time and remotely the patients’ routines thus paving the way for telerehabilitation scenarios. Here, we report the results of a feasibility study in a cohort of 16 stroke patients. All our patients showed a high degree of comfort in our immersive VR system and they reported very high scores of ownership and agency in embodiment and satisfaction questionnaires. Furthermore, and notably, we found that behavioral performances in our VR tasks correlated with the patients’ clinical scores (Fugl-Meyer scale) and they could thus be used to assess improvements during the rehabilitation program. While further studies are needed, our results clearly support the feasibility and effectiveness of VR-based motor rehabilitation processes.

Remote iVR for Nutrition Education: From Design to Evaluation

While different crowdsourcing platforms promote remote data collection, experiments in the immersive Virtual Reality (iVR) research community are predominantly performed in person. The COVID-19 pandemic, however, has forced researchers in different disciplines, including iVR, to seriously consider remote studies. In this paper, we present a remote study using the Immersive Virtual Alimentation and Nutrition (IVAN) application, designed to educate users about food-energy density and portion size control. We report on the results of a remote experiment with 45 users using the IVAN app. In IVAN, users actively construct knowledge about energy density by manipulating virtual food items, and explore the concept of portion size control through hypothesis testing and assembling virtual meals in iVR. To explore the feasibility of conducting remote iVR studies using an interactive health-related application for nutrition education, two conditions were devised (interactive vs. passive). The results demonstrate the feasibility of conducting remote iVR studies using health-related applications. Furthermore, the results also indicate that regardless of level of interactivity learners significantly improved their knowledge about portion size control after using the IVAN (p &lt; 0.0001). Adding interactivity, however, suggests that the perceived learning experience of users could be partially affected. Learners reported significantly higher scores for immediacy of control in the interactive condition compared to those in the passive condition (p &lt; 0.05). This study demonstrates the feasibility of conducting an unsupervised remote iVR experiment using a complex and interactive health-related iVR app.

Is Natural Necessary? Human Voice versus Synthetic Voice for Intelligent Virtual Agents

The use of intelligent virtual agents (IVA) to support humans in social contexts will depend on their social acceptability. Acceptance will be related to the human’s perception of the IVAs as well as the IVAs’ ability to respond and adapt their conversation appropriately to the human. Adaptation implies computer-generated speech (synthetic speech), such as text-to-speech (TTS). In this paper, we present the results of a study to investigate the effect of voice type (human voice vs. synthetic voice) on two aspects: (1) the IVA’s likeability and voice impression in the light of co-presence, and (2) the interaction outcome, including human–agent trust and behavior change intention. The experiment included 118 participants who interacted with either the virtual advisor with TTS or the virtual advisor with human voice to gain tips for reducing their study stress. Participants in this study found the voice of the virtual advisor with TTS to be more eerie, but they rated both agents, with recorded voice and with TTS, similarly in terms of likeability. They further showed a similar attitude towards both agents in terms of co-presence and building trust. These results challenge previous studies that favor human voice over TTS, and suggest that even if human voice is preferred, TTS can deliver equivalent benefits.

Inter- and Transcultural Learning in Social Virtual Reality: A Proposal for an Inter- and Transcultural Virtual Object Database to be Used in the Implementation, Reflection, and Evaluation of Virtual Encounters

Visual stimuli are frequently used to improve memory, language learning or perception, and understanding of metacognitive processes. However, in virtual reality (VR), there are few systematically and empirically derived databases. This paper proposes the first collection of virtual objects based on empirical evaluation for inter-and transcultural encounters between English- and German-speaking learners. We used explicit and implicit measurement methods to identify cultural associations and the degree of stereotypical perception for each virtual stimuli (n = 293) through two online studies, including native German and English-speaking participants. The analysis resulted in a final well-describable database of 128 objects (called InteractionSuitcase). In future applications, the objects can be used as a great interaction or conversation asset and behavioral measurement tool in social VR applications, especially in the field of foreign language education. For example, encounters can use the objects to describe their culture, or teachers can intuitively assess stereotyped attitudes of the encounters.

Collaborative Work in Augmented Reality: A Survey

In Augmented Reality (AR), users perceive virtual content anchored in the real world. It is used in medicine, education, games, navigation, maintenance, product design, and visualization, in both single-user and multi-user scenarios. Multi-user AR has received limited attention from researchers, even though AR has been in development for more than two decades. We present the state of existing work at the intersection of AR and Computer-Supported Collaborative Work (AR-CSCW), by combining a systematic survey approach with an exploratory, opportunistic literature search. We categorize 65 papers along the dimensions of space, time, role symmetry (whether the roles of users are symmetric), technology symmetry (whether the hardware platforms of users are symmetric), and output and input modalities. We derive design considerations for collaborative AR environments, and identify under-explored research topics. These include the use of heterogeneous hardware considerations and 3D data exploration research areas. This survey is useful for newcomers to the field, readers interested in an overview of CSCW in AR applications, and domain experts seeking up-to-date information.

Telepresence Social Robotics towards Co-Presence: A Review

Telepresence robots are becoming popular in social interactions involving health care, elderly assistance, guidance, or office meetings. There are two types of human psychological experiences to consider in robot-mediated interactions: (1) telepresence, in which a user develops a sense of being present near the remote interlocutor, and (2) co-presence, in which a user perceives the other person as being present locally with him or her. This work presents a literature review on developments supporting robotic social interactions, contributing to improving the sense of presence and co-presence via robot mediation. This survey aims to define social presence, co-presence, identify autonomous “user-adaptive systems” for social robots, and propose a taxonomy for “co-presence” mechanisms. It presents an overview of social robotics systems, applications areas, and technical methods and provides directions for telepresence and co-presence robot design given the actual and future challenges. Finally, we suggest evaluation guidelines for these systems, having as reference face-to-face interaction.

Comparison of Object Detection in Head-Mounted and Desktop Displays for Congruent and Incongruent Environments

Virtual reality technologies, including head-mounted displays (HMD), can provide benefits to psychological research by combining high degrees of experimental control with improved ecological validity. This is due to the strong feeling of being in the displayed environment (presence) experienced by VR users. As of yet, it is not fully explored how using HMDs impacts basic perceptual tasks, such as object perception. In traditional display setups, the congruency between background environment and object category has been shown to impact response times in object perception tasks. In this study, we investigated whether this well-established effect is comparable when using desktop and HMD devices. In the study, 21 participants used both desktop and HMD setups to perform an object identification task and, subsequently, their subjective presence while experiencing two-distinct virtual environments (a beach and a home environment) was evaluated. Participants were quicker to identify objects in the HMD condition, independent of object-environment congruency, while congruency effects were not impacted. Furthermore, participants reported significantly higher presence in the HMD condition.

Hospital Greenspaces and the Impacts on Wayfinding and Spatial Experience: An Explorative Experiment Through Immersive Virtual Environment (IVE) Techniques

BACKGROUND

Navigating large hospitals can be very challenging due to the functional complexity as well as the evolving changes and expansions of such facilities. Hospital wayfinding issues could lead to stress, negative mood, and poor healthcare experience among patients, staff, and family members.

OBJECTIVES

A survey-embedded experiment was conducted using immersive virtual environment (IVE) techniques to explore people's wayfinding performance and their mood and spatial experience in hospital circulation spaces with or without visible greenspaces.

METHODS

Seventy-four participants were randomly assigned to either group to complete wayfinding tasks in a timed session. Participants' wayfinding performances were interpreted using several indicators, including task completion, duration, walking distance, stop, sign-viewing, and route selection. Participants' mood states and perceived environmental attractiveness and atmosphere were surveyed; their perceived levels of presence in the IVE hospitals were also reported.

RESULTS

The results revealed that participants performed better on high complexity wayfinding tasks in the IVE hospital with visible greenspaces, as indicated by less time consumed and shorter walking distance to find the correct destination, less frequent stops and sign viewing, and more efficient route selection. Participants also experienced enhanced mood states and favorable spatial experience and perceived aesthetics in the IVE hospital with visible greenspaces than the same environment without window views. IVE techniques could be an efficient tool to supplement environment-behavior studies with certain conditions noted.

CONCLUSIONS

Hospital greenspaces located at key decision points could serve as landmarks that positively attract people's attention, aid wayfinding, and improve their navigational experience.

A survey of challenges and methods for Quality of Experience assessment of interactive VR applications

User acceptance of virtual reality (VR) applications is dependent on multiple aspects, such as usability, enjoyment, and cybersickness. To fully realize the disruptive potential of VR technology in light of recent technological advancements (e.g., advanced headsets, immersive graphics), gaining a deeper understanding of underlying factors and dimensions impacting and contributing to the overall end-user experience is of great benefit to hardware manufacturers, software and content developers, and service providers. To provide insight into user behaviour and preferences, researchers conduct user studies exploring the influence of various user-, system-, and context-related factors on the overall Quality of Experience (QoE) and its dimensions. When planning and executing such studies, researchers are faced with numerous methodological challenges related to study design aspects, such as specification of dependant and independent variables, subjective and objective assessment methods, preparation of test materials, test environment, and participant recruitment. Approaching these challenges from a multidisciplinary perspective, this paper reviews different aspects of performing perception-based QoE assessment for interactive VR applications and presents options and recommendations for research methodology design. We provide an overview of different influence factors and dimensions that may affect the overall QoE, with a focus on presence, immersion, and discomfort. Furthermore, we address ethical and practical issues regarding participant choice and test material, present different assessment methods and measures commonly used in VR research, and discuss approaches to choosing study duration and location. Lastly, we provide a concise analysis of key challenges that need to be addressed in future studies centered around VR QoE.

Next-generation deep learning based on simulators and synthetic data

Deep learning (DL) is being successfully applied across multiple domains, yet these models learn in a most artificial way: they require large quantities of labeled data to grasp even simple concepts. Thus, the main bottleneck is often access to supervised data. Here, we highlight a trend in a potential solution to this challenge: synthetic data. Synthetic data are becoming accessible due to progress in rendering pipelines, generative adversarial models, and fusion models. Moreover, advancements in domain adaptation techniques help close the statistical gap between synthetic and real data. Paradoxically, this artificial solution is also likely to enable more natural learning, as seen in biological systems, including continual, multimodal, and embodied learning. Complementary to this, simulators and deep neural networks (DNNs) will also have a critical role in providing insight into the cognitive and neural functioning of biological systems. We also review the strengths of, and opportunities and novel challenges associated with, synthetic data.

VR Realism Scale-Revalidation of contemporary VR headsets on a Polish sample

This paper presents validation of the VR Simulation Realism Scale on a Polish sample. The scale enables a self-report measurement of perceived realism of a virtual environment in four main aspects of such realism-scene realism, audience behavior realism, audience appearance realism and sound realism. However, since the development of the original scale, the VR technology significantly changed. We aimed to respond to that change and revalidate the original measure in the contemporary setting. For the purpose of scale validation, data was gathered from six studies with 720 participants in total. Five experiments and one online survey were conducted to examine psychometric properties of the scale in accordance with the Standards for Educational and Psychological Testing. Evidence based on internal structure, relations to other variables and test content was obtained. The factorial structure of the original scale was tested and confirmed. The connections between realism and immersion, presence, aesthetics were verified. A suppressed relationship between realism and positive affect was discovered. Moreover, it was confirmed that scale result is dependent on the quality of VR graphics. Results of the analyses provide the evidence that the VR Simulation Realism Scale is a well-established tool that might be used both in science and in VR development. However, further research needs to be done to increase external validity and predictive power of the scale.

Human versus chatbot: Understanding the role of emotion in health marketing communication for vaccines

Based on the theoretical framework of agency effect, this study examined the role of affect in influencing the effects of chatbot versus human brand representatives in the context of health marketing communication about HPV vaccines. We conducted a 2 (perceived agency: chatbot vs. human) × 3 (affect elicitation: embarrassment, anger, neutral) between-subject lab experiment with 142 participants, who were randomly assigned to interact with either a perceived chatbot or a human representative. Key findings from self-reported and behavioral data highlight the complexity of consumer-chatbot communication. Specifically, participants reported lower interaction satisfaction with the chatbot than with the human representative when anger was evoked. However, participants were more likely to disclose concerns of HPV risks and provide more elaborate answers to the perceived human representative when embarrassment was elicited. Overall, the chatbot performed comparably to the human representative in terms of perceived usefulness and influence over participants' compliance intention in all emotional contexts. The findings complement the Computers as Social Actors paradigm and offer strategic guidelines to capitalize on the relative advantages of chatbot versus human representatives.

Nature in virtual reality improves mood and reduces stress: evidence from young adults and senior citizens

Large populations worldwide have been deprived from nature experiences due to mass quarantines and lockdowns during the COVID-19 pandemic, and face a looming mental health crisis. Virtual reality offers a safe and practical solution to increase nature exposure. This research examined the effects of virtual nature using a within-subject design with young adults (Study 1) and senior citizens (Study 2). Results from the young adult sample showed that walking in a virtual forest reduced negative affect due to enhanced nature connectedness, and reduced stress measured by heart rate. Consistently, the senior citizen sample reported improved positive affect due to enhanced nature connectedness after the virtual nature walk. Our findings unveil the underlying mechanism of how virtual nature may improve psychological well-being and demonstrated how virtual nature can be used as an intervention to promote mental health.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10055-021-00604-4.

Body Ownership of Anatomically Implausible Hands in Virtual Reality

Manipulating sensory and motor cues can cause an illusionary perception of ownership of a fake body part. Presumably, the illusion can work as long as the false body part's position and appearance are anatomically plausible. Here, we introduce an illusion that challenges past assumptions on body ownership. We used virtual reality to switch and mirror participants' views of their hands. When a participant moves their physical hand, they see the incongruent virtual hand moving. The result is an anatomically implausible configuration of the fake hand. Despite the hand switch, participants reported significant body ownership sensations over the virtual hands. In the first between-group experiment, we found that the strength of body ownership over the incongruent hands was similar to that of congruent hands. Whereas, in the second within-group experiment, anatomical incongruency significantly decreased body ownership. Still, participants reported significant body ownership sensations of the switched hands. Curiously, we found that perceived levels of agency mediate the effect of anatomical congruency on body ownership. These findings offer a fresh perspective on the relationship between anatomical plausibility and assumed body ownership. We propose that goal-directed and purposeful actions can override anatomical plausibility constraints and discuss this in the context of the immersive properties of virtual reality.

Experiences of Stroke Survivors and Clinicians With a Fully Immersive Virtual Reality Treadmill Exergame for Stroke Rehabilitation: A Qualitative Pilot Study

Use of VR-games is considered a promising treatment approach in stroke rehabilitation. However, there is little knowledge on the use and expectations of patients and health professionals regarding the use of treadmill walking in a fully immersive virtual environment as a rehabilitation tool for gait training for stroke survivors. The objectives of the current study were to determine whether stroke survivors can use fully immersive VR utilizing modern HMDs while walking on a treadmill without adverse effects, and to investigate the experiences of stroke survivors and clinicians after testing with focus on acceptability and potential utilization in rehabilitation. A qualitative research design with semi-structured interviews was used to collect data. Five stroke survivors and five clinicians participated in the study and tested a custom-made VR-game on the treadmill before participating in individual semi-structured interview. Data were analyzed through thematic analysis. The analysis of the interview data identified two main categories: (1) experiencing acceptability through safety and motivation, and (2) implementing fully immersive VR in rehabilitation. Both stroke survivors' and clinicians enjoyed the treadmill-based VR-game and felt safe when using it. The stroke survivors experienced motivation for exercising and achievement by fulfilling tasks during the gaming session as the VR-game was engaging. The clinicians found additional motivation by competing in the game. Both groups saw a potential for use in gait rehabilitation after stroke, on the premise of individual adaptation to each patient's needs, and the technology being easy to use. The findings from this qualitative study suggest that a fully immersive treadmill-based VR-game is acceptable and potentially useful as part of gait rehabilitation after stroke, as it was positively received by both stroke survivors and clinicians working within stroke rehabilitation. The participants reported that they experienced motivation in the game through safety, engagement and achievement. They also saw the potential of implementing such a setup in their own rehabilitation setting. Elements that enable safety and engaging experience are important to maintain when using a fully immersive VR-game in stroke rehabilitation.