Carolin Wienrich

This paper presents the first systematic investigation of how congruence in visual self-representation influences self-perception and behavior. We span a continuum from the physical self through avatars with graded self-similarity to clearly dissimilar avatars in virtual reality (VR). In a 1x4 within-user study, participants completed movement and quiz tasks in either physical reality or a digital twin environment in VR, where they embodied one of three avatars: a photorealistic self-similar avatar, a dissimilar same-gender avatar, or a dissimilar opposite-gender avatar. Subjective measures included presence, sense of embodiment, self-identification, and perceived change, and were complemented by an objective movement metric of behavioral change. Compared to physical reality, VR, even with a self-similar avatar, produced lower presence, a weaker sense of embodiment, and reduced self-identification, revealing a persistent gap in visual congruence. Within VR, self-similar avatars enhanced body ownership, self-location, and self-identification relative to dissimilar avatars. Conversely, dissimilar avatars produced measurable behavioral changes compared with self-similar ones. Gender cues, however, had little impact in gender-neutral tasks. Overall, the findings show that photorealistic self-similar avatars reinforce embodiment and self-identification. However, VR still falls short of achieving congruence with physical reality, underscoring key challenges for avatar realism and ecological validity.

Social Virtual Reality (SVR) allows users to meet and build relationships through embodied avatars and real-time interaction in virtual spaces. While embodiment can strengthen social connections and presence, it can also intensify negative encounters, making SVR particularly vulnerable to harassment. Despite frequent reports of verbal, visual, and “physical” violations in SVR, little is known about how harassment reshapes users' self-perception, including their sense of embodiment, self-identification, closeness, and avatar customization preferences. We conducted a controlled experiment with 52 participants who experienced either a neutral or a harassment condition in a scenario modeled after real SVR incidents. Participants perceived the harassing peer as significantly more negative, annoying, and disturbing than the neutral peer. Contrary to prior reports, harassment did not significantly affect well-being measures, including emotional state, self-esteem, and physiological arousal, within this controlled scenario. However, participants reported stronger bodily change, attributed more of their own attitudes and emotions to their avatars, and increased interpersonal distance when personal space was invaded. Self-reported coping strategies included ignoring, stepping back, using humor, and retaliating. Notably, avatar customization preferences shifted across conditions. Participants in the neutral condition favored personalized avatars, whereas those in the harassment condition more frequently preferred anonymity in public spaces. Together, these findings demonstrate that harassment in SVR not only exploits embodiment but also reshapes self-perception. We further contribute methodological insights into how harassment can be ethically and reproducibly studied in controlled SVR–like experiments.

The global prevalence of mental health disorders has created a substantial treatment gap. To support clinicians and increase access to care, researchers in the field of Artificial Intelligence (AI) and Virtual Reality (VR) have investigated technology-mediated psychotherapy for years. However, research about stakeholders' concerns and their readiness to use AI in psychotherapy remains scarce. This study focuses on a user-centered approach to accommodate patients’ concerns and, based on the results, implement measures to foster self-disclosure and trust towards an embodied AI therapist in VR. First, we conducted an online study with mental health patients (N = 152), which identified data autonomy and transparency as their primary ethical concerns. In a subsequent in-person VR study (N = 90) we compared effects of increased data autonomy and transparency on self-disclosure and trust towards an embodied AI therapist. Results indicated that higher data autonomy led to greater self-disclosure, while transparency had no significant effect. Manipulating data autonomy and transparency did not affect perceived trust, though exploratory calculations revealed that women reported significantly higher trust levels than men. These findings illuminate patients' priorities and provide implications for technical designs for AI-driven mental health care.

Integrated Virtual Reality (IVR) systems are central to avatar-mediated use cases in Virtual Reality (VR), reconstructing users' movements on avatars. They differ primarily in their tracking architectures, which determine how completely and accurately users' movements are captured and reconstructed on avatars. Many current IVR systems reduce user-worn hardware, trading reconstruction accuracy against cost and setup complexity, yet their impact on user experience and task performance across use cases remains underexplored. We compared three reduced user-worn IVR systems. Each system has distinct technical approaches: (1) Captury (markerless outside-in optical tracking), (2) Meta Movement SDK (markerless inside-out optical tracking), and (3) Vive Trackers (marker-based outside-in optical tracking with IMUs). In a 3x5 mixed-design, participants performed five tasks, simulating different use cases, to probe distinct aspects of these systems. No system consistently outperformed the others. Meta excelled in hand-based, fast-paced interactions, while Captury and Vive performed better in lower-body tasks and during full-body pose observation. These findings underscore the need to evaluate reduced user-worn IVR systems within the specific use case. We offer practical guidance for system selection based on use-case demands and released our tasks as an open-source, extensible framework to support future evaluations for selecting IVR systems.

Intelligent voice assistants (IVAs) are widely used, but they also risk influencing users without their knowledge. The anthropomorphic nature of IVAs can tempt users to disclose more personal information and trust IVAs more than intended. Therefore, targeted training is necessary to sensitize users and protect them from the persuasive potential of IVAs. This study developed and evaluated two online training modules designed to promote persuasion literacy among student samples. The modules cover the anthropomorphic characteristics of IVAs, their persuasive power, and potential countermeasures. The results indicate that the training improves understanding of persuasion by IVAs, raises awareness of their persuasive potential, and promotes recognition of persuasion attempts. Additionally, the training modules reduce anthropomorphic perceptions of IVAs and reinforce psychological aspects to ensure privacy and self-determined interaction. The training modules provide an innovative approach to enhancing the competent use of IVAs. As a result, they represent an exciting approach for research and educational institutions to further explore and promote persuasion literacy in the context of IVAs and other AI-related applications. Therefore, this work contributes to enhancing the accessibility of digital educational programs.

Autonomous vehicles allow people to focus on parallel tasks while the vehicle handles the driving task itself. This enables new opportunities like mobile workspaces. This paper explores the conceptualization and prototyping of a collaborative workspace in autonomous vehicles. Through a user-centered design approach, we developed a concept that utilizes the space of the vehicle interior, particularly windows, as interactive display surfaces. A prototype was simulated in virtual reality to empirically investigate its influence on collaborative work. Our work focused on two research questions: 1) How should a collaborative workspace in an autonomous vehicle be designed to utilize the unique spatial properties of an autonomous vehicle and 2) to what extend the proposed design supports Workspace Awareness, Social and Spatial Presence - factors of successful remote collaboration. The results of the empirical study indicate that including the utilization of the vehicle interior significantly improves Workspace Awareness and Social Presence compared to a layout centered only on the windshield as interaction surface. However, no significant differences were observed in Spatial Presence between the two layouts. This research highlights the potential of spatial interactions to transform autonomous vehicles into effective collaborative workspaces by leveraging the spatial affordances of the vehicle interior. It underscores the importance of user-centered design and utilizing simulation in virtual reality for the development of applications for non-driving related tasks. This work contributes to the understanding of how autonomous vehicles can be adapted for collaborative work, opening new possibilities for mobile workspaces.