The Impact of a Self-Avatar on Cognitive Load in Immersive Virtual Reality

The use of a self-avatar inside an immersive virtual reality system has been shown to have important effects on presence, interaction and perception of space. Based on studies from linguistics and cognition, in this paper we demonstrate that a self-avatar may aid the participant’s cognitive processes while immersed in a virtual reality system. In our study participants were asked to memorise pairs of letters, perform a spatial rotation exercise and then recall the pairs of letters. In a between-subject factor they either had an avatar or not, and in a within-subject factor they were instructed to keep their hands still or not. We found that participants who both had an avatar and were allowed to move their hands had significantly higher letter pair recall. There was no significant difference between the other three conditions. Further analysis showed that participants who were allowed to move their hands, but could not see the self-avatar, usually didn’t move their hands or stopped moving their hands after a short while. We argue that an active self-avatar may alleviate the mental load of doing the spatial rotation exercise and thus improve letter recall. The results are further evidence of the importance of an appropriate self-avatar representation in immersive virtual reality

The Effect of Anthropometric Properties of Self-Avatars on Action Capabilities in Virtual Reality

The field of Virtual Reality (VR) has seen a steady exponential uptake in the last decade and is being continuously incorporated into areas of popular interest like healthcare, training, recreation and gaming. This steady upward trend and prolonged popularity has resulted in numerous extravagant virtual environments, some that aim to mimic real-life experiences like combat training, while others intend to provide unique experiences that may otherwise be difficult to recreate like flying over ancient Egypt as a bird. These experiences often showcase highly realistic graphics, intuitive interactions and unique avatar embodiment scenarios with the help of various tracking sensors, high definition graphic displays, sound systems, etc. The literature suggests that estimates and affordance judgments in VR scenarios such as the ones described above are affected by the properties and the nature of the avatar embodied by the user. Therefore, to provide users with the finest experiences it is crucial to understand the interaction between the embodied self and the action capabilities afforded by it in the surrounding virtual environment. In a series of studies aimed at exploring the effect of gender matched body-scaled self-avatars on the user\u27s perception, we investigate the effect of self-avatars on the perception of size of objects in an immersive virtual environment (IVE) and how this perception affects the actions one can perform as compared to the real world. In the process, we make use of newer tracking technology and graphic displays to investigate the perceived differences between real world environments and their virtual counterparts to understand how the spatial properties of the environment and the embodied self-avatars affect affordances by means of passability judgments. We describe techniques for creation and mapping VR environments onto their real world counterparts and the creation of gender matched body-scaled self-avatars that provides real time full-body tracking. The first two studies investigate how newer graphical displays and off-the-shelf tracking devices can be utilized to create salient gender matched body-scaled self-avatars and their effect on the judgment of passability as a result of the embodied body schema. The study involves creating complex scripts that automate the process of mapping virtual worlds onto their real world counterparts within a 1cm margin of error and the creation of self-avatars that match height, limb proportions and shoulder width of the participant using tracking sensors. The experiment involves making judgments about the passability of an adjustable doorway in the real world and in a virtual to-scale replica of the real world environment. The results demonstrated that the perception of affordances in IVEs is comparable to the real world but the behavior leading to it differs in VR. Also, the body-scaled self-avatars generated provide salient information yielding performance similar to the real world. Several insights and guidelines related to creating veridical virtual environments and realistic self-avatars were achieved from this effort. The third study investigates how the presence of body-scaled self-avatars affects the perception of size of virtual handheld objects and the influence of the person-plus-virtual-object system created by lifting the said virtual object on passability. This is crucial to understand as VR simulations now often utilize self-avatars that carry objects while maneuvering through the environment. How they interact with these handheld objects can influence what they do in critical scenarios where split second decisions can change the outcome like combat training, role-playing games, first person shooting, thrilling rides, physiotherapy, etc. It has also been reported that the avatar itself can influence the perception of size of virtual objects, in turn influencing action capabilities. There is ample research on different interaction techniques to manipulate objects in a virtual world but the question about how the objects affect our action capabilities upon interaction remains unanswered, especially when the haptic feedback associated with holding a real object is mismatched or missing. The study investigates this phenomenon by having participants interact with virtual objects of different sizes and making frontal and lateral passability judgments to an adjustable aperture similar to the first experiment. The results suggest that the presence of self-avatars significantly affects affordance judgments. Interestingly, frontal and lateral judgments in IVEs seem to similar unlike the real world. Investigating the concept of embodied body schema and its influence on action-capabilities further, the fourth study looks at how embodying self-avatars that may vary slightly from your real world body affect performance and behavior in dynamic affordance scenarios. In this particular study, we change the eye height of the participants in the presence or absence of self-avatars that are either bigger, smaller or the same size as the participant. We then investigate how this change in eye height and anthropometric properties of the self-avatar affects their judgments when crossing streets with oncoming traffic in virtual reality. We also evaluate any changes in the perceived walking speed as a result of embodying altered self-avatars. The findings suggest that the presence of self-avatars results in safer crossing behavior, however scaling the eye height or the avatar does not seem to affect the perceived walking speed. A detailed discussion on all the findings can be found in the manuscript

An ‘In the Wild’ Experiment on Presence and Embodiment using Consumer Virtual Reality Equipment

Consumer virtual reality systems are now becoming widely available. We report on a study on presence and embodiment within virtual reality that was conducted ‘in the wild’, in that data was collected from devices owned by consumers in uncontrolled settings, not in a traditional laboratory setting. Users of Samsung Gear VR and Google Cardboard devices were invited by web pages and email invitation to download and run an app that presented a scenario where the participant would sit in a bar watching a singer. Each participant saw one of eight variations of the scenario: with or without a self-avatar; singer inviting the participant to tap along or not; singer looking at the participant or not. Despite the uncontrolled situation of the experiment, results from an in-app questionnaire showed tentative evidence that a self-avatar had a positive effect on self-report of presence and embodiment, and that the singer inviting the participant to tap along had a negative effect on self-report of embodiment. We discuss the limitations of the study and the platforms, and the potential for future open virtual reality experiments

Examining the Effects of Altered Avatars on Perception-Action in Virtual Reality

In virtual reality avatars are animated graphical representation of a person embedded in a virtual environment. Previous research has illustrated the benefits of having an avatar when perceiving aspects of virtual reality. We studied the effect that a non-faithful, or altered, avatar had on the perception of one\u27s action capabilities in VR. In Experiment 1, one group of participants acted with a normal, or faithful, avatar and the other group of participants used an avatar with an extended arm, all in virtual reality. In Experiment 2, the same methodology and procedure was used as in Experiment 1, except only the calibration phase occurred in VR, while the remaining reaches were completed in the real world. All participants performed reaches to various distances. The results of these studies show that calibration to altered dimensions of avatars is possible after receiving feedback while acting with the altered avatar. Further, calibration occurred more quickly when feedback was initially used to transition from a normal avatar to an altered avatar than when later transitioning from the altered avatar arm back to the normal avatar arm without feedback. The implications of these findings for training in virtual reality simulations and transfer back to the real world are also discussed

The Role of Action in Affordance Perception Using Virtual Reality

Space perception in virtual reality (VR) is distorted. Does action in conjunction with an avatar\u27s presence improve perception in VR? Participants judged whether a virtual ball was within reach. Condition 1 was perception-only, where the participant was not allowed to move nor could see their arms. Condition 2 was perception with nonvisible action, where the participant could move their real arm to reach but could not see an avatar representation of the arm. Condition 3 was perception with visible action, where the participant could move and see a virtual hand that corresponded to the actual arm movement. Participants overestimated their own reach by about 15% in the avatar condition and the proprioceptive condition. The perception-only condition was the most accurate (only 5% overestimation). Response times were comparable for distances within reach but got longer in Conditions 2 and 3 when the ball was out of reach. The affordance responses (‘yes’ or ‘no’) did not correlate with response time, postural instability, nor with the head leaning forward. Instead, affordance responses mapped onto the mean magnitude of head movements. Specifically, complexity measured by effort-to-compress (ETC), which was lowest at the action boundary in the avatar condition, may helped to differentiate between experimental conditions. Our results point to the lack of expected haptic feedback as a critical variable, and the utility of complex exploration that may have contributed to the difference between the avatar and the perception-only condition

Applying Affordances Scale as a Design Method – Case Virtual Reality Course Design

Practitioners including designers and teachers developing Virtual Reality (VR) courses are facing a question regarding the strengths and subject areas in which VR-enriched courses might have the highest potential compared to conventional courses. The present study develops a survey scale to assess and match industry managers’ requirements for skills for working life. The same scale was surveyed among two different groups of higher education students participating in conventional courses and a VR-aided course. The results indicate that the industry requirements were higher than met by the both course types. However, the results highlight a set of skills for which the VR courses have the highest potential compared to conventional courses. These skills include self-monitoring, independent thinking and understanding, adapting and applying new ideas into practice as well as creativity as a latent class theme. The paper discusses example designs based on these skills whose development is suggested to be included in the future VR course designs.Practitioners including designers and teachers developing Virtual Reality (VR) courses are facing a question regarding the strengths and subject areas in which VR-enriched courses might have the highest potential compared to conventional courses. The present study develops a survey scale to assess and match industry managers’ requirements for skills for working life. The same scale was surveyed among two different groups of higher education students participating in conventional courses and a VR-aided course. The results indicate that the industry requirements were higher than met by the both course types. However, the results highlight a set of skills for which the VR courses have the highest potential compared to conventional courses. These skills include self-monitoring, independent thinking and understanding, adapting and applying new ideas into practice as well as creativity as a latent class theme. The paper discusses example designs based on these skills whose development is suggested to be included in the future VR course designs.Peer reviewe

Substitutional reality:using the physical environment to design virtual reality experiences

Experiencing Virtual Reality in domestic and other uncontrolled settings is challenging due to the presence of physical objects and furniture that are not usually defined in the Virtual Environment. To address this challenge, we explore the concept of Substitutional Reality in the context of Virtual Reality: a class of Virtual Environments where every physical object surrounding a user is paired, with some degree of discrepancy, to a virtual counterpart. We present a model of potential substitutions and validate it in two user studies. In the first study we investigated factors that affect participants' suspension of disbelief and ease of use. We systematically altered the virtual representation of a physical object and recorded responses from 20 participants. The second study investigated users' levels of engagement as the physical proxy for a virtual object varied. From the results, we derive a set of guidelines for the design of future Substitutional Reality experiences

Posture Affects Affordance Perception of Reachability in Virtual Reality

Tasks such as standing and reaching require differing levels of postural stability. Postural equilibrium is necessary to perceive the location of objects (Lee, Pacheco, & Newell, 2018). Visual perception of whether an object is within reach was investigated while standing upright. Participants viewed a 3D virtual reality (VR) environment with a stimulus object (red ball) placed at different egocentric distances. Participants made affordance judgements while in a standard stance condition as well as two separate active balance conditions (yoga tree pose, and toe-to-heel pose). Feedback on accuracy was not provided, and participants were not allowed to attempt to reach. Response time, affordance judgments (reachable, not reachable), and head movements were recorded on each trial. Consistent with recent research on reaching ability (Weast & Proffitt, 2018), the perceived action boundary occurred around 120% of arm length, indicating overestimation of perceived reaching ability. Response times increased with distance, and were shortest for the most difficult yoga tree pose. Head movement amplitude increased with increases in balance demands. Surprisingly, the coefficient of variation was comparable in the two poses that had increased balance requirements, and was more extreme in a less constrained, ostensibly easier pose for the shortest and longest distances. More complex descriptors of postural sway (i.e. multifractality) were predictive of perception while in the tree pose and the toe-to-heel pose, as compared to control stance. This demonstrates that standard measures of central tendency are not sufficient for describing multiscale interactions of postural dynamics in functional tasks

Empowerment and embodiment for collaborative mixed reality systems: Empowerment and Embodiment

We present several mixed‐reality‐based remote collaboration settings by using consumer head‐mounted displays. We investigated how two people are able to work together in these settings. We found that the person in the AR system will be regarded as the “leader” (i.e., they provide a greater contribution to the collaboration), whereas no similar “leader” emerges in augmented reality (AR)‐to‐AR and AR‐to‐VRBody settings. We also found that these special patterns of leadership only emerged for 3D interactions and not for 2D interactions. Results about the participants' experience of leadership, collaboration, embodiment, presence, and copresence shed further light on these findings