Summary: Virtual reality can help reduce painful sensations following touch people with nerve damage experience.
Source: University of Plymouth
We all feel physical pain in different ways, but people with nerve injuries often have a dysfunctional pain suppression system, making them particularly prone to discomfort.
Now researchers have uncovered that virtual reality (VR) can reduce types of pain typically seen in patients with nerve injuries – and that VR can boost the dysfunctional pain suppression system, giving people with chronic pain a possible game-changing hope.
Dr Sam Hughes, Lecturer in Psychology at the University of Plymouth, led the study focusing on conditioned pain modulation (CPM) – a pain inhibitory pathway in humans.
He and colleagues at Imperial College London had previously published work showing that watching soothing 360-degree scenes of the Arctic in virtual reality can help to ease pain symptoms similar to those experienced during sunburn.
In the current study they showed that VR can also reduce pain symptoms such as prickling and pain following touch, that are often seen in patients with nerve injury.
They have also gone one step further and measured VR’s direct effects on CPM. CPM is dysfunctional in patients with nerve injury, so by knowing what can enhance its action, scientists can help to stimulate the body’s natural pain inhibiting process.
The study, published in The Journal of Pain, showed that 360-degree scenes of the Arctic in virtual reality had an effect on the CPM efficiency, while the 2D versions of the same scenes (described as ‘sham VR’) reduced CPM efficiency.
Dr Hughes said: “It’s brilliant that we’ve seen these results as it shows more evidence that virtual reality can not only reduce pain perception in human models of chronic pain, but also gives us insight into the mechanisms behind this effect. The next step of course is to conduct the study with people who experience chronic pain to see if it works for them.
“If it does work, it could be a really helpful in forming part of ongoing pain management by helping to target the dysfunctions in the brain that underpin chronic pain.”
About this neurotech research news
Source: University of Plymouth Contact: Amy King – University of Plymouth Image: The image is in the public domain
•There was no effect of real or sham VR on acute pain thresholds.
•Real and sham VR had no effect on pain ratings during the CPM conditioning period.
•VR attenuated mechanical pain sensitivity in a human surrogate model of central sensitization.
Virtual reality (VR) has been shown to produce analgesic effects during different experimental and clinical pain states. Despite this, the top-down mechanisms are still poorly understood.
In this study, we examined the influence of both a real and sham (ie, the same images in 2D) immersive arctic VR environment on conditioned pain modulation (CPM) and in a human surrogate model of central sensitization in 38 healthy volunteers. CPM and acute heat pain thresholds were assessed before and during VR/sham exposure in the absence of any sensitization.
In a follow-on study, we used the cutaneous high frequency stimulation model of central sensitization and measured changes in mechanical pain sensitivity in an area of heterotopic sensitization before and during VR/sham exposure. There was an increase in CPM efficiency during the VR condition compared to baseline (P < .01).
In the sham condition, there was a decrease in CPM efficiency compared to baseline (P < .01) and the real VR condition (P < .001). Neither real nor sham VR had any effect on pain ratings reported during the conditioning period or on heat pain threshold. There was also an attenuation of mechanical pain sensitivity during the VR condition indicating a lower sensitivity compared to sham (P < .05).
We conclude that exposure to an immersive VR environment has no effect over acute pain thresholds but can modulate dynamic CPM responses and mechanical hypersensitivity in healthy volunteers.