In face-to-face interactions, people rely on facial expressions, body posture, and further verbal and non-verbal cues to infer others’ internal states. While collaborative virtual reality (VR) enables rich shared experiences, it offers fewer expressive cues, making perceiving mental states like attention, intention, or cognitive load (CL) more difficult. Rather than replicating real-world cues, we investigated how augmenting collaborative VR with real-time visualizations of users’ CL impacts social presence. We first conducted semi-structured interviews (N = 6) and an online survey (N = 54) to elicit user needs and design preferences for CL visualizations. These insights informed the development of a collaborative VR application evaluated in a lab experiment (N = 30). Participants engaged in verbal explanation tasks of varying difficulty while their CL was displayed using different visualizations (pie charts, bar charts, brain diagrams), including a no-visualization control condition. Social presence was measured using the Networked Minds Social Presence Inventory and augmented via post-experiment interviews. Our results show that in difficult tasks, pie chart visualizations helped sustain co-presence, while all diagrams supported affective understanding. These findings demonstrate the potential of intuitive CL visualizations to foster social connectedness, helping inform future designs of collaborative VR.

Figure 1: Illustration of a remote social interaction between two users waving each other in an augmented environment.The users wearing a head-mounted display are represented by a realistic avatar, with additional progressively abstract avatars displayed to showcase the varying levels of realism used in the experiment.

Professional and personal lives are undergoing a shift from physical to virtual meetings. While this offers numerous advantages, such as increased spatial autonomy, it also poses risks to the social bonds among employees, families, and friends. Even current collaborative virtual reality (VR) applications cannot bridge the separation in virtual meetings, as they do not provide a sense of social connectedness comparable to in-person interaction. Reasons include limited behavioral realism of VR avatars, e.g., in displayed body movements. We systematically investigated how realistic body movements influence Social Presence in a collaborative VR task. We explored three types of motion-tracking mechanisms: no motion-tracking beyond controllers, hand-tracking, and full-body motion-tracking with hand-tracking. To examine their influence on Social Presence, we designed a spatial collaboration task based on insights gained from semi-structured interviews ( N = 6). Subsequently, we conducted a controlled VR experiment ( N = 18), in which participants' counterparts employed the various motion-tracking technologies while performing said task. Our results demonstrate that realistic body movements do not influence self-reported Social Presence in VR. Nevertheless, they entail an increased interpersonal distance among users, attributable to a subconscious influence on Social Presence.