Virtual reality (VR) technology allows users to feel a virtual body as if it was their own (i.e., body ownership illusion). Previous studies have explored how the visual realism of the user's virtual body influences the sense of body ownership in VR, focusing on the aspect of anthropomorphism. However, the effect of photorealism, another element that characterizes the visual realism of a virtual human, has not been systematically examined in the context of body ownership illusion. Therefore, we investigate the effect of the rendering style of virtual hands on the sense of body ownership, hypothesizing that the effect is affected by the rendering style of the virtual environment. In addition, we examine the effect of photorealism on presence (i.e., the sense of being there), as existing studies have offered inconsistent evidence. To this aim, we conducted a 3 × 3 mixed-design remote VR experiment (N = 117) that factored in the rendering styles of both the virtual hand and the environment and analyzed the subjective data from the questionnaire. The results suggest that neither the rendering style of virtual hands nor the consistency of the rendering style between the virtual hand and the environment influenced the sense of body ownership. Nevertheless, the more photorealistically the virtual environment was rendered, the stronger the presence. Our results indicate that different dimensions of virtual body realism affect the sense of body ownership differently, thereby highlighting the importance of applying a suitable classification of realism to understand the body ownership illusion for virtual bodies more in depth.

The rapid development of artificial intelligence (AI) has fundamentally transformed creative work practices in the design industry. Existing studies have identified both opportunities and challenges for creative practitioners in their collaboration with generative AI and explored ways to facilitate effective human-AI co-creation. However, there is still a limited understanding of designers' collaboration with AI that supports creative processes distinct from generative AI. To address these gaps, this study focuses on understanding designers' collaboration with decision-making AI, which supports the convergence process in the creative workflow, as opposed to the divergent process supported by generative AI. Specifically, we conducted a case study at an online advertising design company to explore how professional graphic designers at the company perceive the impact of decision-making AI on their creative work practices. The case company incorporated an AI system that predicts the effectiveness of advertising design into the design workflow as a decision-making support tool. Findings from interviews with 12 designers identified how designers trust and rely on AI, its perceived benefits and challenges, and their strategies for navigating the challenges. Based on the findings, we discuss design recommendations for integrating decision-making AI into the creative design workflow.

Teleoperating social robots requires operators to “speak as the robot,” as local users would favor robots whose appearance and voice match. This study focuses on real-time altered auditory feedback (AAF), a method to transform the acoustic traits of one’s speech and provide feedback to the speaker, to transform the operator’s self-representation toward “becoming the robot.” To explore whether AAF with voice transformation (VT) matched to the robot’s appearance can influence the operator’s self-representation and ease the task, we experimented with three conditions: no VT (No-VT), only VT (VT-only), and VT with AAF (VT-AAF), where participants teleoperated a robot to verbally serve real passersby at a bakery. The questionnaire results demonstrate that VT-AAF changed the participants’ self-representation to match the robot’s character and improved participants’ subjective teleoperating experience, while task performance and implicit measures of self-representation were not significantly affected. Notably, 87% of the participants preferred VT-AAF the most.

Can you speak the way you desire without feeling the pressure to conform to standards of speaking? In this study, we investigated the impact of user-controlled voice manipulation and listening to recordings of model speakers on self-perceptions of voice and speech. Quantitative analysis showed that there was a significant improvement in the perceived confidence of tone by listening to model speakers, but there were no significant improvements due to voice manipulation. Qualitative analysis of interviews revealed that participants responded positively to the visual and auditory feedback provided by the voice manipulation software. The participants also evaluated the quality of model speakers to decide whether or not they wanted to refer to them for speech practice. Based on the results of these analyses, we summarized the design implications for a speech practice system that would allow further investigation of the impact of the system on self-perceptions of speech performance.

In Virtual Reality, self-touch (ST) stimulation is a promising method of sense of body ownership (SoBO) induction that does not require an external effector. However, its applicability to dysmorphic bodies has not been explored yet and remains uncertain due to the requirement to provide incongruent visuomotor sensations. In this, paper, we studied the effect of ST stimulation on dysmorphic hands via haptic retargeting, as compared to a classical external-touch (ET) stimulation, on the SoBO. Our results indicate that ST can induce similar levels of dysmorphic SoBO than ET stimulation, but that some types of dysmorphism might decrease the ST stimulation accuracy due to the nature of the re-targeting that they induce.

The 2022 VGTC Virtual Reality Best Dissertation Award goes to Nami Ogawa, a 2020 graduate from the University of Tokyo, for her dissertation entitled, “Effect of Self-Avatar Anthropomorphism on Perception and Behavior in Virtual Environments.”

Cinematic virtual reality, or 360° video, provides viewers with an immersive experience, allowing them to enjoy a video while moving their head to watch in any direction. However, there is an inevitable problem of feeling fear of missing out (FOMO) when viewing a 360° video, as only a part of the video is visible to the viewer at any given time. To solve this problem, we developed a technique to present a panoramic thumbnail of a full 360° video to users through a head-mounted display. With this technique, the user can grasp the overall view of the video as needed. We conducted an experiment to evaluate the FOMO, presence, and quality of viewing experience while using this technique compared to normal viewing without it. The results of the experiment show that the proposed technique relieved FOMO, the quality of viewing experience was improved, and there was no difference in presence. We also investigated how users interacted with this new interface based on eye tracking and head tracking data during viewing, which suggested that users used the panoramic thumbnail to actively explore outside their field of view.

In this article, we introduce a concept called "virtual co-embodiment", which enables a user to share their virtual avatar with another entity (e.g., another user, robot, or autonomous agent). We describe a proof-of-concept in which two users can be immersed from a first-person perspective in a virtual environment and can have complementary levels of control (total, partial, or none) over a shared avatar. In addition, we conducted an experiment to investigate the influence of users' level of control over the shared avatar and prior knowledge of their actions on the users' sense of agency and motor actions. The results showed that participants are good at estimating their real level of control but significantly overestimate their sense of agency when they can anticipate the motion of the avatar. Moreover, participants performed similar body motions regardless of their real control over the avatar. The results also revealed that the internal dimension of the locus of control, which is a personality trait, is negatively correlated with the user's perceived level of control. The combined results unfold a new range of applications in the fields of virtual-reality-based training and collaborative teleoperation, where users would be able to share their virtual body.

Hand interaction techniques in virtual reality often exploit visual dominance over proprioception to remap physical hand movements onto different virtual movements. However, when the offset between virtual and physical hands increases, the remapped virtual hand movements are hardly self-attributed, and the users become aware of the remapping. Interestingly, the sense of self-attribution of a body is called the sense of body ownership (SoBO) in the field of psychology, and the realistic the avatar, the stronger is the SoBO. Hence, we hypothesized that realistic avatars (i.e., human hands) can foster self-attribution of the remapped movements better than abstract avatars (i.e., spherical pointers), thus making the remapping less noticeable. In this article, we present an experiment in which participants repeatedly executed reaching movements with their right hand while different amounts of horizontal shifts were applied. We measured the remapping detection thresholds for each combination of shift directions (left or right) and avatar appearances (realistic or abstract). The results show that realistic avatars increased the detection threshold (i.e., lowered sensitivity) by 31.3 percent than the abstract avatars when the leftward shift was applied (i.e., when the hand moved in the direction away from the body-midline). In addition, the proprioceptive drift (i.e., the displacement of self-localization toward an avatar) was larger with realistic avatars for leftward shifts, indicating that visual information was given greater preference during visuo-proprioceptive integration in realistic avatars. Our findings quantifiably show that realistic avatars can make remapping less noticeable for larger mismatches between virtual and physical movements and can potentially improve a wide variety of hand-remapping techniques without changing the mapping itself.

Preventing users from walking through virtual boundaries (e.g., walls) is an important issue to be addressed in room-scale virtual environments (VEs), considering the safety and design limitations. Sensory feedback from wall collisions has been shown to be effective; however, it can disrupt the immersion. We assumed that a greater sense of presence would discourage users from walking through walls and conducted a two-factor between-subjects experiment (N = 92) that controls the anthropomorphism (realistic or abstract) and visibility (full-body or hand-only) of self-avatars. We analyzed the participants' behaviors and the moment they first penetrated the wall in game-like VEs that gradually instigated participants to penetrate the walls. The results showed that the realistic full-body self-avatar was the most effective for discouraging the participants from penetrating the walls. Furthermore, the participants with lower presence tended to walk through the walls sooner. This study can contribute to applications that require realistic user responses in VEs.

Studies have shown that the sense of body ownership towards virtual humanoid avatars with additional body parts can be successfully elicited when synchronous visuomotor and/or visuotactile feedback is given. In an interactive virtual reality (VR) application, however, it is difficult for users to uninterruptedly observe the added body parts, especially when they are attached to the backs of the avatars. Thus, the embodiment of such body parts needs to be achieved using limited synchronous visuomotor feedback. Commonly, it is specifically done by looking at a virtual mirror reflection of the avatar’s movement. However, the methodology of eliciting the sense of body ownership in such conditions remains to be studied.

How does the representation of an embodied avatar influence the way in which one perceives the scale of a virtual environment? In virtual reality, it is common to embody avatars of various appearances, from abstract to realistic. It is known that changes in the realism of virtual hands affect the self-body perception, including body ownership. However, the influence of self-avatar realism on the perception of non-body objects has not been investigated. Considering the theory that the scale of the external environment is perceived relative to the size of one's body (body-based scaling), it can be hypothesized that the realism of an avatar affects not only body ownership but also the fidelity of the avatar with respect to our own body as a metric. Therefore, this study examines how avatar realism affects perceived object sizes as the size of the virtual hand changes. In the experiment, we manipulate the level of realism (realistic, iconic, and abstract) and size (veridical and enlarged) of the virtual hand and measure the perceived size of a cube. The results show that the size of the cube is perceived to be smaller when the virtual hand is enlarged compared to when it is veridical, indicating that the participants perceive the sizes of objects based on the size of the avatar, only in the case of a highly realistic hand. Our findings indicate that the more realistic the avatar, the stronger is the sense of embodiment including body ownership, which fosters scaling the size of objects using the size of the body as a fundamental metric. This provides evidence that self-avatar appearances affect how we perceive not only virtual bodies but also virtual spaces.

How does the representation of an embodied avatar influence the way in which a human perceives the scale of a virtual environment? It has been shown that the scale of the external environment is perceived relative to the size of one's body. However, the influence of avatar realism on the perceived scale has not been investigated, despite the fact that it is common to embody avatars of various representations, from iconic to realistic. This study examined how avatar realism would affect perceived graspable object sizes as the size of the avatar hand changes. In the experiment, we manipulated the realism (high, medium, and low) and size (veridical and enlarged) of the avatar hand, and measured the perceived size of a cube. The results showed that the size of the cube was perceived to be smaller when the avatar hand was enlarged for all degrees of realism of the hand. However, the enlargement of the avatar hand had a greater influence on the perceived cube size for the highly realistic avatar than for the medium-level and low-level realism conditions. This study shed new light on the importance of the avatar representation in a three-dimensional user interface field, in how it can affect the manner in which we perceive the scale of a virtual environment.