Xiaru Meng, Yulan Ju, Christopher Changmok Kim, Yan He, Giulia Barbareschi, Kouta Minamizawa, Kai Kunze, and Matthias Hoppe. 2025. A Placebo Concert: The Placebo Effect for Visualization of Physiological Audience Data during Experience Recreation in Virtual Reality. In Proceedings of the 2025 CHI Conference on Human Factors in Computing Systems (CHI '25). Association for Computing Machinery, New York, NY, USA, Article 807, 1–16. https://doi.org/10.1145/3706598.3713594

A core use case for Virtual Reality applications is recreating real-life scenarios for training or entertainment. Promoting physiological responses for users in VR that match those of real-life spectators can maximize engagement and contribute to more co-presence. Current research focuses on visualizations and measurements of physiological data to ensure experience accuracy. However, placebo effects are known to influence performance and self-perception in HCI studies, creating a need to investigate the effect of visualizing different types of data (real, unmatched, and fake) on user perception during event recreation in VR. We investigate these conditions through a balanced between-groups study (n=44) of uninformed and informed participants. The informed group was provided with the information that the data visualizations represented previously recorded human physiological data. Our findings reveal a placebo effect, where the informed group demonstrated enhanced engagement and co-presence. Additionally, the fake data condition in the informed group evoked a positive emotional response.

https://doi.org/10.1145/3706598.3713594

Perceiving and altering the sensation of internal physiological states, such as heartbeats, is key for biofeedback and interoception. Yet, wearable devices used for this purpose can feel intrusive and typically fail to deliver stimuli aligned with the heart’s location in the chest. To address this, we introduce Heartbeat Resonance, which uses low-frequency sound waves to create non-contact haptic sensations in the chest cavity, mimicking heartbeats. We conduct two experiments to evaluate the system’s effectiveness. The first experiment shows that the system created realistic heartbeat sensations in the chest, with 78.05 Hz being the most effective frequency. In the second experiment, we evaluate the effects of entrainment by simulating faster and slower heart rates. Participants perceived the intended changes and reported high confidence in their perceptions for +15% and -30% heart rates. This system offers a non-intrusive solution for biofeedback while creating new possibilities for immersive VR environments.

Waseem Hassan, Liyue Da, Sonia Elizondo, and Kasper Hornbæk. 2025. Heartbeat Resonance: Inducing Non-contact Heartbeat Sensations in the Chest. In Proceedings of the 2025 CHI Conference on Human Factors in Computing Systems (CHI '25). Association for Computing Machinery, New York, NY, USA, Article 913, 1–22. https://doi.org/10.1145/3706598.3713959

To enhance focused eating and dining socialization, previous Human-Food Interaction research has indicated that external devices can support these dining objectives and immersion. However, methods that focus on the food itself and the diners themselves have remained underdeveloped. In this study, we integrated biofeedback with food, utilizing diners’ heart rates as a source of the food’s appearance to promote focused eating and dining socialization. By employing LED lights, we dynamically displayed diners’ real-time physiological signals through the transparency of the food. Results revealed significant effects on various aspects of dining immersion, such as awareness perceptions, attractiveness, attentiveness to each bite, and emotional bonds with the food. Furthermore, to promote dining socialization, we established a “Sharing Bio-Sync Food” dining system to strengthen emotional connections between diners. Based on these findings, we developed tableware that integrates biofeedback into the culinary experience.