UMD-led Study Supports Role for VR in Pain Relief

If you sit on a tack, it’s likely to hurt. But pain is more than a physical experience; it’s a phenomenon affected by our emotions, past experiences and the people around us.

Apparently, pain relief is similarly complex.

A new study published in Nature’s journal npj Digital Medicine reveals that watching someone else experience pain relief, whether it’s another human or a digital representation of one, can meaningfully reduce the hurt we feel ourselves. But context matters: Who we are watching and how they are presented influence the strength of this placebo effect.

For this study, a team led by researchers from the University of Maryland, College Park and the University of Maryland, Baltimore, including co-authors from the University of Maryland Institute for Health Computing (UM-IHC), investigated how observational vicarious learning—learning by watching others’ therapeutic outcome—can induce firsthand placebo analgesia, a phenomenon in which pain eases without an active treatment.

Participant responses revealed that the placebo effect varied depending on whether the demonstrator receiving a treatment was a human or a cartoon-like avatar, and whether the individual was presented in immersive virtual reality (VR) or standard video. The team’s findings suggest that both avatars and immersive technology can play a valuable role in mediating pain relief through the placebo effect.

“This study provides new insight into how learning from others—across different forms and formats—can shape how we experience pain reduction ourselves,” said Luana Colloca, an MPower Professor of Pain and Translational Symptom Science in UMB’s School of Nursing and director of the Placebo Beyond Opinions Center. The project is part of the MPowering the State Initiative, which leverages the complimentary research prowess of UMCP and UMB for the good of all Marylanders. “What surprised us most was that immersive virtual environments and even avatars could amplify placebo analgesia. This opens new possibilities for integrating digital tools into pain management strategies.”

In the National Institutes of Health-funded study, 47 participants watched videos of a human demonstrator receiving painful heat stimulation. Study participants continued to watch as two creams, one blue and one green, were applied to the affected area, and the subject appeared to feel relief from one of them—even though the creams were identical and neither had analgesic properties.

Later, participants received the same heat stimulation and the same two creams. Even without an explicit promise of improvement, participants reported less pain when using the cream they had seen “work” on the demonstrator, providing evidence that pain relief can be socially learned without overt suggestion.

With the immersive reality expertise of UMCP Computer Science Professor Amitabh Varshney, dean of the College of Computer, Mathematical, and Natural Sciences, the researchers also investigated whether study participants’ experiences differed depending on the technology—using VR goggles and surround sound versus standard video on a screen—and whether the demonstrator was an actual human or a digital avatar.

When participants used immersive VR, avatars were significantly more effective at eliciting pain relief in study participants than human actors; however, human actors produced stronger effects using a normal screen. For any clinical application, the work underscores the importance of tailoring digital interventions to the delivery format.

Colloca noted that VR’s ability to “tap into social learning mechanisms” makes it powerful, and that the tool is already being used in clinical settings, from rehab to mental health to medical training. Watching how people engage with virtual systems and understanding the factors that affect their experiences can inform an array of next-generation digital health care tools for pain management and beyond, she said.

Varshney, who has a joint appointment in the University of Maryland Institute for Advanced Computer Studies, agreed the technology merits further study as a component of pain relief and other therapies.

“This research shows how VR avatars can inspire empathy and produce powerful placebo effects for pain management in immersive environments. It underscores the vast potential of immersive digital therapeutics to transform health care,” he said.

In addition to Varshney, UMCP authors of the study included Barbara Brawn, director of strategic initiatives for UM-IHC and managing director of the Center for Medical Innovations in Extended Reality (MIXR); and Jonathan Heagerty and Sida Li, researchers for the Mixed/Augmented/Virtual/Reality Community (MAVRIC) initiative, both of whom hold UM-IHC appointments.