Life-Sized Virtual Health Coaches in VR: Rapport-Building Behaviors and Their Effects on Health Attitudes and Proxemics
Year: 2026
Type: conference-paper
Abstract: Access to effective health behavior change counseling remains limited, motivating scalable alternatives such as embodied conversational agents (ECAs). Virtual reality (VR) uniquely enables life-sized, spatially co-present ECAs that users can treat as genuine social partners, making interpersonal distance physically meaningful in ways that 2D screen deployments cannot support. We designed life-sized virtual health coaches that deliver brief motivational interviewing-inspired counseling and compared a rapport-building condition, incorporating relational dialogue, self-disclosure, affiliative humor, and agent-initiated proxemic approach, against a stationary, task-focused control. In a counterbalanced within-subjects study (N=40), participants showed short-term improvements in self-reported TTM-based health attitudes, with greater motivation gains following the rapport-building condition. Self-reported trust and working alliance with the agent were high in both conditions and did not significantly differ. Critically, a behavioral approach-distance task revealed that participants stood reliably closer to the agent following the rapport-building interaction, indicating that behavioral proxemics can complement self-report measures in capturing relational responses. Qualitative interviews showed that users interpreted agent approach as a meaningful relational signal, while highlighting the importance of timing, pacing, and boundary negotiation. We discuss design implications for rapport-aligned proxemic behaviors in life-sized VR health coaching agents.
Authors: Zhuorui Yong, Chongyang Wang, Timothy Bickmore
Institution: Northeastern University
Language: English
Subfield: Social Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: hybrid
OpenAlex ID: W7207870355