The certain sense of awareness we have about the way our bodies look, feel, and function is defined by many psychologists as “embodiment”. We are able to tell that our hand is a part of our body, and innately understand how to use it as a tool. However, we are also able to distinguish this from a pencil that we may hold between our fingers, which we recognize as being an entity separate from our bodies, yet still able to be used as an extension of our hand for writing or drawing. Studies have revealed that embodiment is actually much more flexible than one might think. In the same way that our ocular system fills in visual gaps in the forms we observe (which can result in optical illusions), our brain can fill in tactile gaps, which especially seems to be common when paired with a visual parallel to supplement the sensation taking place. In the “Rubber Hand” experiment conducted by Matthew Botvinick and Jonathan Cohen, participants were told to put one of their hands on a table in front of them, which was then covered by a curtain. A rubber arm was placed next to the curtain, where it was visible to the participant. A paint brush was used to gently touch both the hidden, real hand and the visible, rubber hand. A significant portion of the participants “felt” a sensation of touch on the rubber hand they were looking at being brushed in front of them (Botvinick).
When placed into a simulated environment, people’s perception and cognizance of their own body becomes distorted in a similar way. Our senses are already unreliable, but in a virtual world, where it is no longer as easy to predict patterns according to what is typical of real life, the discrepancy between what a person perceives and what stimuli are actually present grows significantly. This is why researchers and medical professionals are looking at Virtual Reality as a field of research with loads of potential; it has become clear that this booming technology has applications beyond just gaming and entertainment. Virtual Reality has a place in the medical field- many have argued that it is effective as a means of pain therapy, beyond just meditation and anxiety-calming techniques, as it has the capacity to temporarily alter our sense of embodiment.
A group of researchers at Radboud University Medical Center of Nijmegen in the Netherlands studied the effects of VR on people’s sensitivity to electrical stimulation. After collecting answers from a preliminary survey determining creativity and impressionability of the group, they separated participants into sections based on their predicted level of immersion into the 360° VR world. Participants were told to explore the virtual world within their headset. One group remained in this exploratory mode throughout the duration of the study, without background music. Another group explored with background music. The remaining group was given the task of virtual shooting balls into a hoop within the VR world. Meanwhile, they were all attached to a device that would send a gentle shock into their arm at increasing voltages periodically. The control group did not participate in the VR experience. It was found that not only did the participants report a statistically significant increase in electrical detection thresholds with the use of Virtual Reality devices, but the more immersed a person was in the experience, the greater their detection threshold would be (Lier). In other words, the amount of sensation a person was able to pick up on decreased as their experience in VR was made more and more “active”. In a way, their receptive neural pathways were preoccupied with engaging in the VR world. This may also tie into the idea of embodiment- without seeing the visual cue that there is an electrical pulse being sent into their arm, it recedes from the forefront of participants’ minds. Under the most immersed condition, the participants are focused on the coordination of their virtual arms -comparable to the rubber arm in Botvinick and Cohen’s study- as they attempt to shoot balls into a hoop. There is a limit to the amount of attention we can delegate to different sensations, which is why we are less likely to pick up on physical pain when in the midst of a VR experience.
VR has proven to have a calming and pain-reducing effect on subjects experiencing both acute and chronic pain. In addition, it has been shown that any way to increase engagement has the capacity to lower pain sensation. For example, the pairing of VR with binaural noise reduced pain in research participants significantly more than VR on its own. The advent of the Metaverse and all its subparts is scary, and tends to deter people. However, VR, and extended reality as a whole, deserves attention from the medical field. It has the potential to help so many people.