There are two qualifications I would like to make to the argument for use of virtual reality in pain therapy. First, research has shown that VR on its own is not as effective, nor as immersive as it could potentially be. To have the best results for patients, it has been shown that pairing VR therapy with binaural audio is the most effective.
A study by the name of “Evaluation of a VR system for Pain Management using Binaural Acoustic Stimulation” was conducted by Francisco Perales and his team to measure the changes in pain perception in VR paired with binaural audio through measuring sweat activity on the skin. This was done by calculating the electrical conductivity of participants’ skin. Heart rate and temperature were also measured at different points in the study. It was found that in VR (regardless of whether or not it was paired with binaural sound), all participants reported lower levels of pain. Even after taking the headset off, participants reported an average 1.7 point improvement in pain level on a scale of 1-10. Electrodermal activity decreased and temperature increased, both respectively in significant amounts. The biggest difference from the control group was seen with the research participants who were both immersed in VR and listening to binaural beats. These individuals had the lowest levels of reported pain during and after the experience, and physiologically, they were the most calm. This setup requires the deepest level of immersion, as the subject is receiving multi-dimensional sensory input both visually and through audio. The idea of VR and binaural sound as a distractor to lessen anxiety is applicable here, but there seems to be more to it than that. In addition to this new, simulated sense of embodiment introduced by VR, there is the element of sound. Music in general has been shown to be an effective pain-reducing mechanism, as it stimulates the hippocampus in a way that significantly decreases the secretion of cortisol. By making the music dimensional, these researchers were able to engage participants on a new level. This study served as a huge breakthrough in discovering what avenues of stimulation work for reducing pain.
Secondly, I would like to address the negative stigma around XR in general with regards to sensory overload. XR has been scrutinized for its descent into the realm of superrealism, which has in some cases been proven to be unhealthy for the brain if exposed repeatedly. It is scary- we are getting closer and closer to a reality that we can control, that we can manipulate in any way we see fit. VR has the ability to fully immerse users, to the extent that their embodiment when it comes to their physical body becomes muddled with the virtual body within the VR world. Many see this as more of an issue than an innovation. Because it requires such a deep level of immersion, It distracts a person from their senses outside of VR to the point where they need time to readjust between transitioning from the real to the virtual world and vice versa. In addition, because VR only simulates depth and perspective using computer graphics, our eyes are doing a lot more work to make sense of our space. Walter Greenleaf of Stanford’s Virtual Human Interaction Lab explains that when looking through a VR headset, our visual system is activating to see far into the distance (as it might appear within the digital scene) when in reality the point we are concentrating on is only a couple of centimeters from our eyes (LaMotte). One term that has been coined for this dizzying sensation is visual-vestibular somatosensory conflict. For this reason, repeated or prolonged use of this technology could be disorienting.
This is a very important point to consider. Because XR, VR, AR, and MR are such new technologies that are still in development, it is hard to know exactly what the long term effects of using them are. There is still so much that we don’t know about how it affects us physiologically and mentally, as this is something we can only observe over time. However, pain reducing therapy is something that could be done in small doses. It is not as perceptually demanding as a VR game might be. In many of the research studies mentioned in this essay, the virtual therapy module was typically very simple: looking at a box in space or swatting a fly. It is not the complexity of the experience that makes it immersive, but the quality of alignment between the subjects actions and those of their virtual selves. As long as those match up, the sense of embodiment persists.