Virtual Avatar Research Articles

Virtual, Real or Mixed: How Surrounding Objects Influence the Sense of Embodiment in Optical See-Through Experiences?

This paper studies the sense of embodiment of virtual avatars in Mixed Reality (MR) environments visualized with an Optical See-Through display. We investigated whether the content of the surrounding environment could impact the user’s perception of their avatar, when embodied from a first-person perspective. To do so, we conducted a user study comparing the sense of embodiment toward virtual robot hands in three environment contexts which included progressive quantities of virtual content: real content only, mixed virtual/real content, and virtual content only. Taken together, our results suggest that users tend to accept virtual hands as their own more easily when the environment contains both virtual and real objects (mixed context), allowing them to better merge the two “worlds”. We discuss these results and raise research questions for future work to consider.

Proprioceptive Stimulation Added to a Walking Self-Avatar Enhances the Illusory Perception of Walking in Static Participants

When immersed in virtual reality, users who view their body as a co-located virtual avatar that reflects their movements, generally develop a sense of embodiment whereby they perceive the virtual body to be their own. One aspect of the sense of embodiment is the feeling of agency over the avatar, i.e., the feeling that one is producing the movements of the avatar. In contexts such as physical rehabilitation, telepresence and gaming, it may be useful to induce a strong sense of agency in users who cannot produce movements or for whom it is not practical to do so. Being able to feel agency over a walking avatar without having to produce walking movements could be especially valuable. Muscle vibrations have been shown to produce the proprioceptive perception of movements, without any movement on the part of the user. The objectives of the current study were to: 1-determine if the addition of lower-limb muscle-vibrations with gait-like patterns to a walking avatar can increase the illusory perception of walking in healthy individuals who are standing still; 2-compare the effects of the complexity of the vibration patterns and of their synchronicity on the sense of agency and on the illusory perception of walking. Thirty participants viewed a walking avatar from a first-person perspective, either without muscle vibrations or with one of four different patterns of vibrations. These five conditions were presented pairwise in a two-alternative forced choice paradigm and individually presented, after which participants answered an embodiment questionnaire. The displacement of center of pressure of the participants was measured throughout the experiment. The results show that all patterns of proprioceptive stimulation increased the sense of agency to a similar degree. However, the condition in which the proprioceptive feedback was realistic and temporally aligned with the avatar’s leg movements led to significantly larger anteroposterior sway of the center of pressure. The frequency of this sway matched the cadence of the avatar’s gait. Thus, congruent and realistic proprioceptive stimulation increases the feeling of agency, the illusory perception of walking and the motor responses of the participants when viewing a walking avatar from a first-person perspective.

Remotely Perceived: Investigating the Influence of Valence on Self-Perception and Social Experience for Dyadic Video-Conferencing With Personalized Avatars

Avatar use on video-conference platforms has found dual purpose in recent times as a potential method for ensuring privacy and improving subjective engagement with remote meeting, provided one can also ensure a minimal loss in the quality of social interaction and sense of personal presence. This work focuses on interactions of this sort through real-time motion captured 3D personalized virtual avatars in a 2D video-conferencing context. Our experiments were designed with the intention of exploring previously defined perceptual illusions that occur with avatar-use in Virtual and Augmented Reality settings, outside of the immersive technological domains where they are normally measured. The research described here was aimed at empirically evaluating three separate dimensions of human-avatar interaction. The first was humans-as-avatars, with experimental conditions that were designed to measure changes to subjective perceptions of self-face ownership and self-concept. The second focus was other-perception, with the unique design of the studies outlined below among the first to measure social presence in a video-call between two human-driven avatars. The third emphasis was on the experiential content involved in avatar use, as there were measurements for emotion induction, fatigue and behavior change included in the data collection. The results describe some evidence for face and body ownership, while participants also reported high levels of social presence with the other avatar, indicating that avatar cameras could be a favorable alternative to non-camera feeds in video conferencing. There were also some useful insights gained regarding emotion elicitation in non-video vs. avatar conditions, as well as avatar-induced behavior change.

Comparing virtual vs real faces expressing emotions in children with autism: An eye-tracking study

Difficulties in processing emotional facial expressions is considered a central characteristic of children with autism spectrum condition (ASC). In addition, there is a growing interest in the use of virtual avatars capable of expressing emotions as an intervention aimed at improving the social skills of these individuals. One potential use of avatars is that they could enhance facial recognition and guide attention. However, this aspect needs further investigation. The aim of our study is to assess differences in eye gaze processes in children with ASC when they see avatar faces expressing emotions compared to real faces. Eye-tracking methodology was used to compare the performance of children with ASC between avatar and real faces. A repeated-measures general linear model was adopted to understand which characteristics of the stimuli could influence the stimuli’s fixation times. Survival analysis was performed to understand differences in exploration behaviour between avatar and real faces. Differences between emotion recognition accuracy and the number of fixations were evaluated through a paired t-test. Our results confirm that children with autism have higher capacities to process and recognize emotions when these are presented by avatar faces. Children with autism are more attracted to the mouth or the eyes depending on the stimulus type (avatar or real) and the emotion expressed by the stimulus. Also, they are more attracted to avatar faces expressing negative emotions (anger and sadness), and to real faces expressing surprise. Differences were not found regarding happiness. Finally, they show a higher degree of exploration of avatar faces. All these elements, such as interest in the avatar and reduced attention to the eyes, can offer important elements in planning an efficient intervention.

Using Body Ownership to Modulate the Motor System in Stroke Patients

Recent findings suggest that body ownership can activate the motor system in the absence of movement execution. Here, we investigated whether such a process promotes motor recovery in stroke patients. A group of patients with left-hemisphere damage (N = 12) and chronic motor deficits completed an immersive virtual reality training (three sessions of 15 min each week for 11 weeks). Patients sat still and either experienced (first-person perspective) or did not experience (third-person perspective) illusory ownership over the body of a standing virtual avatar. After the training, in which the avatar walked around a virtual environment, only patients who experienced the illusion improved gait and balance. We argue that representing the virtual body as their own allowed patients to access motor functioning and promoted motor recovery. This procedure might be integrated with rehabilitative approaches centered on motor execution. These findings also have an impact on the knowledge of the motor system in general.

A Preliminary Embodiment Short Questionnaire

Consumer virtual reality (VR) technologies have made embodying a virtual avatar during an immersive experience more feasible. The sense of embodiment toward that virtual avatar can be characterized and measured along three factors: self-location, agency, and body ownership. Some measures of embodiment have been previously proposed, but most have not been validated or do not measure the three individual factors of embodiment. In this paper, we present the construction and validation of a preliminary version of a short questionnaire that not only addresses these factors of embodiment but can also be used as an in-VR questionnaire, which we call the pESQ. By using and validating the pESQ, we provide results indicating that foot tracking significantly improves self-location and agency, and that an avatar significantly improves body ownership.

“Let’s Go, Baby Forklift!”: Fandom Governance and the Political Power of Cuteness in China

This article describes how the Chinese state borrows from the culture of celebrity fandom to implement a novel strategy of governing that we term “fandom governance.” We illustrate how state-run social media employed fandom governance early in the COVID-19 pandemic when the country was convulsed with anxiety. As the state faced a crisis, state social media responded with a propagandistic display of state efficacy, broadcasting a round-the-clock livestream of a massive emergency hospital construction project. Chinese internet users playfully embellished imagery from the livestream. They unexpectedly transformed the construction vehicles into cute personified memes, with Baby Forklift and Baby Mud Barfer (a cement mixer) among the most popular. In turn, state social media strategically channeled this playful engagement in politically productive directions by resignifying the personified vehicles as celebrity idols. Combining social media studies with cultural and linguistic anthropology, we offer a processual account of the semiotic mediations involved in turning vehicles into memes, memes into idols, and citizens into fans. We show how, by embedding cute memes within modules of fandom management such as celebrity ranking lists, state social media rendered them artificially vulnerable to a fall in status. Fans, in turn, rallied around to “protect” these cute idols with small but significant acts of digital devotion and care, organizing themselves into fan circles and exhorting each other to vote. In elevating the memes to the status of celebrity idols, state social media thereby created a disposable pantheon of virtual avatars for the state, and consolidated state power around citizens’ voluntary response to vulnerability. We analyze fandom governance as a new development in the Chinese state’s long history of governing citizens through the management of emotion.

Owning a virtual body entails owning the value of its actions in a detection-of-deception procedure

The feeling of owning one's body underlies human self-awareness. Body-ownership illusions allow temporarily modulating body ownership, which has observable effects on the behavior and cognitive processes. However, the extent of those effects is unclear. Here, we investigated whether illusory ownership of a virtual body extended to ownership of the value/meaning of its actions. A variation of detection-of-deception procedure (Concealed Information Test) was performed by an embodied virtual avatar (first-person perspective, 1PP), or a non-embodied one (third-person perspective, 3PP), while the skin conductance responses (SCRs) were recorded from passively observing participants. Target stimuli (i.e., concealed information) evoked significantly larger SCRs than the neutral ones only when the avatar was embodied (in 1PP). Such pattern of SCR differences corresponds to that observed when participants perform the task themselves, thus suggesting that the sole experience of owning a virtual body can trigger physiological responses related to the subjective significance of the body's actions.

Virtual Avatar Coaching With Community Context for Adult-Child Dyads with Low Income

ObjectiveExamine the acceptability of an evidence-based, contextually tailored, virtual avatar coaching approach for nutrition education among adult-child dyads with low income. DesignStructured observations and semistructured interviews. SettingLow-income communities in 2 midsized urban areas. ParticipantsFifteen African American adult and child (aged 5–10 years old) dyads recruited from community agencies. Phenomenon of InterestStructured observation during the use of the virtual avatar coaching program and qualitative feedback on program experience after using the program. AnalysisTranscripts were independently coded by 2 trained coders. Content analysis was conducted to determine trends and patterns in responses, and salient quotes were extracted from the manuscripts. ResultsThe program generated dialogue between the children and adults around preferences and dietary habits. Adults and children described the program as being helpful, informative, motivational, and fun. Adults and children liked that the avatar acknowledged them at a personal level, provided accountability, and was tailored to them and their environment. Children wanted the ability to customize the avatar, more gamification, and avatar demonstration of healthy behaviors. Children felt the program would improve their health behaviors and were interested in using it again. Conclusions and ImplicationsThis study highlights information that can be used to improve avatar-based programs for nutrition education with children and their adult caregivers who have low income. Future work should assess the impact of user customization experience, program impact on dietary behaviors, and resources required to scale and maintain the program with community agencies.

EVA 2.0: Emotional and rational multimodal argumentation between virtual agents

Abstract Persuasive argumentation depends on multiple aspects, which include not only the content of the individual arguments, but also the way they are presented. The presentation of arguments is crucial – in particular in the context of dialogical argumentation. However, the effects of different discussion styles on the listener are hard to isolate in human dialogues. In order to demonstrate and investigate various styles of argumentation, we propose a multi-agent system in which different aspects of persuasion can be modelled and investigated separately. Our system utilizes argument structures extracted from text-based reviews for which a minimal bias of the user can be assumed. The persuasive dialogue is modelled as a dialogue game for argumentation that was motivated by the objective to enable both natural and flexible interactions between the agents. In order to support a comparison of factual against affective persuasion approaches, we implemented two fundamentally different strategies for both agents: The logical policy utilizes deep Reinforcement Learning in a multi-agent setup to optimize the strategy with respect to the game formalism and the available argument. In contrast, the emotional policy selects the next move in compliance with an agent emotion that is adapted to user feedback to persuade on an emotional level. The resulting interaction is presented to the user via virtual avatars and can be rated through an intuitive interface.

Upper limb exercise with physical and virtual robots: Visual sensitivity affects task performance

Abstract We investigated the influence of visual sensitivity on the performance of an imitation task with the robot R1 in its virtual and physical forms. Virtual and physical embodiments offer different sensory experience to the users. As all individuals respond differently to their sensory environment, their sensory sensitivity may play a role in the interaction with a robot. Investigating how sensory sensitivity can influence the interactions appears to be a helpful tool to evaluate and design such interactions. Here we asked 16 participants to perform an imitation task, with a virtual and a physical robot under conditions of full and occluded visibility, and to report the strategy they used to perform this task. We asked them to complete the Sensory Perception Quotient questionnaire. Sensory sensitivity in vision predicted the participants’ performance in imitating the robot’s upper limb movements. From the self-report questionnaire, we observed that the participants relied more on visual sensory cues to perform the task with the physical robot than on the virtual robot. From these results, we propose that a physical embodiment enables the user to invest a lower cognitive effort when performing an imitation task over a virtual embodiment. The results presented here are encouraging that following this line of research is suitable to improve and evaluate the effects of the physical and virtual embodiment of robots for applications in healthy and clinical settings.

Study of Full-body Virtual Embodiment Using noninvasive Brain Stimulation and Imaging

ABSTRACT The sense of embodiment in virtual reality is a strong case of body ownership illusion, effectively allowing humans to experience the ownership of a modified, or a completely different body. Virtual embodiment has captured the attention of researchers in various fields, with applications far beyond computer science. Despite the promising applications, little is known about the neural mechanisms behind full-body virtual embodiment. This study investigates the influence of anodal transcranial direct current stimulation of the brain area linked to processing of the bodily self (right temporoparietal junction) to the subjective strength of virtual embodiment and its main constituents, using within-subject experimental design with sham-controlled stimulation. Virtual embodiment was studied using questionnaires, accompanied by brain signals gathered using EEG. Our results suggest that stimulation did not affect the sense of ownership toward the virtual avatar. Borderline strengthening of the perceived sense of agency toward the avatar’s actions was found in the sessions with stimulation.

Predicted Influences of Artificial Intelligence on Nursing Education: Scoping Review.

BackgroundIt is predicted that artificial intelligence (AI) will transform nursing across all domains of nursing practice, including administration, clinical care, education, policy, and research. Increasingly, researchers are exploring the potential influences of AI health technologies (AIHTs) on nursing in general and on nursing education more specifically. However, little emphasis has been placed on synthesizing this body of literature.ObjectiveA scoping review was conducted to summarize the current and predicted influences of AIHTs on nursing education over the next 10 years and beyond.MethodsThis scoping review followed a previously published protocol from April 2020. Using an established scoping review methodology, the databases of MEDLINE, Cumulative Index to Nursing and Allied Health Literature, Embase, PsycINFO, Cochrane Database of Systematic Reviews, Cochrane Central, Education Resources Information Centre, Scopus, Web of Science, and Proquest were searched. In addition to the use of these electronic databases, a targeted website search was performed to access relevant grey literature. s and full-text studies were independently screened by two reviewers using prespecified inclusion and exclusion criteria. Included literature focused on nursing education and digital health technologies that incorporate AI. Data were charted using a structured form and narratively summarized into categories.ResultsA total of 27 articles were identified (20 expository papers, six studies with quantitative or prototyping methods, and one qualitative study). The population included nurses, nurse educators, and nursing students at the entry-to-practice, undergraduate, graduate, and doctoral levels. A variety of AIHTs were discussed, including virtual avatar apps, smart homes, predictive analytics, virtual or augmented reality, and robots. The two key categories derived from the literature were (1) influences of AI on nursing education in academic institutions and (2) influences of AI on nursing education in clinical practice.ConclusionsCurricular reform is urgently needed within nursing education programs in academic institutions and clinical practice settings to prepare nurses and nursing students to practice safely and efficiently in the age of AI. Additionally, nurse educators need to adopt new and evolving pedagogies that incorporate AI to better support students at all levels of education. Finally, nursing students and practicing nurses must be equipped with the requisite knowledge and skills to effectively assess AIHTs and safely integrate those deemed appropriate to support person-centered compassionate nursing care in practice settings.International Registered Report Identifier (IRRID)RR2-10.2196/17490

Modulation of walking speed by the change in motion and shape of the virtual avatar moving alongside

Modulation of walking speed by the change in motion and shape of the virtual avatar moving alongside

Video Synthesis Method for Virtual Avatar Using FACS based GAN

Video Synthesis Method for Virtual Avatar Using FACS based GAN

Virtual Companion for the Elderly: Conceptual Framework

As the proportion of global elderly population increases, there is an accompanying demand for improved care for ageing individuals. Technological developments in fields of machine learning and mobile applications can be leveraged to improve quality of life for elderly individuals. We explore development of virtual companions and chatbots, conducting a detailed literature review. Ultimately, we propose a novel virtual companion that combines emotion, personality, and external knowledge into one virtual companion system. We extend the objective to include design considerations to tailor the proposed virtual companion for needs specific to elderly users. Additional features such as mental health monitoring, cognitive impairment detection, design of a virtual avatar, error recovery and latency, and more are included.

Have We Crossed the Uncanny Valley? Understanding Affinity, Trustworthiness, and Preference for Realistic Digital Humans in Immersive Environments

Developers have long strived to create virtual avatars that are more realistic because they are believed to be preferred over less realistic avatars. However, an “uncanny valley” exists in which avatars trigger aversion when they are almost but not quite realistic. We used a field study to investigate whether users had different affinity, trustworthiness, and preferences for avatars with two levels of realism, one that was close to human-realistic and one a cartoon caricature. We observed behavior, conducted one-on-one interviews, and collected survey data from SIGGRAPH conference attendees who either participated in a live discussion session between two avatars in a VR environment, or observed it via 3D VR headsets or on a large screen 2D video display. Eighteen sessions were conducted over four days, with the same person animating the human-realistic avatar and different guests animating the caricature avatars. The guests who interacted with the human-realistic avatar had a positive experience in the VR environment. The observers had positive evaluations of both avatars while acknowledging their different levels of realism. They rated the human-realistic avatar as more trustworthy, had more affinity for it, and preferred it as a virtual agent. Participants who observed the interview through VR headsets had an even stronger affinity for the human-realistic avatar and stronger preferences for it than those who observed via the 2D screen. Effect sizes ranged from medium to large. Our results suggest that it is now possible to cross the uncanny valley with human-realistic avatars rendered in real time.

Estimating Subjective Argument Quality Aspects From Social Signals in Argumentative Dialogue Systems

Information about a subjective user opinion towards an argument is crucial for argumentative systems in order to present appropriate content and adapt their behaviour to the individual user. However, requesting explicit feedback regarding the discussed arguments is often impractical and can hinder the interaction. To address this issue, we investigate the automatic recognition of user opinions towards arguments that are presented by means of a virtual avatar from social signals. We focus on two different user opinion categories ( convincing and interesting ) and two different types of social signals (facial expressions and eye movement). The recognition is addressed as a supervised learning problem and realized using the argument search evaluation data discussed in previous work. The overall performance is compared to a human annotation on a subset of the collected data. The results show that the machine learning performance is similar to human performance in both recognition tasks.

The Use of Virtual Reality to Influence Motivation, Affect, Enjoyment, and Engagement During Exercise: A Scoping Review

Many adults are physically inactive. While the reasons are complex, inactivity is, in part, influenced by the presence of negative feelings and low enjoyment during exercise. While virtual reality (VR) has been proposed as a way to improve engagement with exercise (e.g., choosing to undertake exercise), how VR is currently used to influence experiencesduringexercise is largely unknown. Here we aimed to summarize the existing literature evaluating the use of VR to influence motivation, affect, enjoyment, and engagement during exercise. A Population (clinical, and healthy), Concept (the extent and nature of research about VR in exercise, including underpinning theories), and Context (any setting, demographic, social context) framework was used. A systematic search of Medline, Scopus, Embase, PsycINFO, and Google Scholar was completed by two independent reviewers. Of 970 studies identified, 25 unique studies were included (n= 994 participants), with most (68%) evaluating VR influences on motivation, affect, enjoyment, and engagement during exercise in healthy populations (n= 8 studies evaluating clinical populations). Two VR strategies were prominent – the use of immersion and the use of virtual avatars and agents/trainers. All studies but one used virtual agents/trainers, suggesting that we know little about the influence of virtual avatars on experiences during exercise. Generally, highly immersive VR had more beneficial effects than low immersive VR or exercise without VR. The interaction between VR strategy and the specific exercise outcome appeared important (e.g., virtual avatars/agents were more influential in positively changing motivation and engagement during exercise, whereas immersion more positively influenced enjoyment during exercise). Presently, the knowledge base is insufficient to provide definitive recommendations for use of specific VR strategies to target specific exercise outcomes, particularly given the numerous null findings. Regardless, these preliminary findings support the idea that VR may influence experiences during exercise via multiple mechanistic pathways. Understanding these underlying mechanisms may be important to heighten effects targeted to specific exercise outcomes during exercise. Future research requires purposeful integration of exercise-relevant theories into VR investigation, and careful consideration of VR definitions (including delineation between virtual avatars and virtual agents), software possibilities, and nuanced extension to clinical populations.

Tendon-Inspired Piezoelectric Sensor for Biometric Application

In this article, a novel sensing structure is proposed to measure tensile loading. The sensing structure is motivated by the operating principle of the tendon. The fibroelastic characteristic of the tendon is implemented by combining sewing and elastic threads with a piezoelectric material, that is, a tendon-inspired piezoelectric sensor. The mechanical deformation of the tendon-inspired piezoelectric sensor was analyzed by applying tensile loading. Additionally, the electrical response according to the given tensile loading was measured and compared with the theoretical expectation. The experimental results found that the sensor outputs can be represented as a linear function along with elongation in a specific range. Furthermore, the motion-detecting capability of the sensor was demonstrated using body supports with seven tendon-inspired piezoelectric sensors. To show the feasibility of its application, a real-time motion detecting system using a virtual avatar was developed. The avatar showed good synchronization with the subject's upper-limb movements. This study provides insight into the sensing characteristics of the tendon-driven piezoelectric sensor and shows the potential for biometric applications.