It's Always Better When We're Together: Physiological Synchrony and Shared Experiences in Social VR

When people share experiences in physically co-located environments, such as attending a music experience, their physiological responses align, reflecting a shared social experience through synchrony. In virtual reality (VR), however, it remains unclear whether physiological synchrony similarly reflects the quality of social experiences. Our study examines how different sensory attendance modalities affect physiological synchrony and perceived shared experience during social VR music experiences. In a within-subject design, participants (N = 66) watched 16 music video clips in dyads, in four attendance modalities: Alone, Voice, Avatar, and Avatar+Voice. We measured physiological responses (electrodermal activity, heart rate, and respiration rate) and subjective measures of presence, social presence, co-presence, social connectedness, user experience, and emotional response. Attending the experience with access to social cues, particularly in the Avatar+Voice condition, significantly strengthened physiological synchrony, presence dimensions, social connectedness and user experiences compared to the Alone condition, where no social indicators were available. Avatars had an overall greater impact than Voice in intensifying shared experiences, indicating that virtual bodies amplify co-experiences both subjectively and physiologically. We demonstrate that physiological synchrony can serve as a measure of co-experience in social VR music settings. Our findings show its potential for evaluating and designing embodied interaction in extended reality (XR), contributing to the optimization of presence dimensions, social connectedness and user experience. We inform XR researchers and practitioners about the role of avatars and voices in shaping shared VR experiences and discuss how synchrony-based measures can support future research and design efforts to understand co-experiences in social XR.