Icy Virtual Reality Freezes Out Pain
/By Pat Anson, PNN Editor
Everyone knows that an ice pack or cold compress can help sooth aching joints and sore muscles. Cold temperatures slow blood circulation, reducing both pain and inflammation.
Researchers at Imperial College London took that basic first aid measure a step further by using virtual reality (VR) to immerse people in scenes of an icy Arctic landscape. And just like real ice, the VR video reduced pain perception and sensitivity.
Findings from the small study, published in the journal Pain Reports, add to growing evidence that VR technology can not only distract people from their pain, but may also activate the body’s pain-fighting response.
“One of the key features of chronic pain is you get increased sensitivity to painful stimuli. This means patients’ nerves are constantly ‘firing’ and telling their brain they are in a heightened state of pain,” first author Sam Hughes, PhD, said in a press release.
"Our work suggests that VR may be interfering with processes in the brain, brainstem and spinal cord, which are known to be key parts of our inbuilt pain-fighting systems and are instrumental in regulating the spread of increased sensitivity to pain.
In the study, 15 healthy volunteers were given a topical cream on the skin of their legs containing capsaicin – the spicy chemical in chili peppers that makes your mouth burn. The capsaicin sensitized the skin, making it more sensitive to pain from a small electric shock.
Participants were then asked to rate their pain on a scale of 0-100 (from ‘no sensation’ to ‘worst pain imaginable’) while looking at a still image of an Arctic scene on a computer monitor or watching this National Geographic video of Arctic exploration through a VR headset.
Researchers found that pain from the capsaicin cream was reduced following the VR immersion. The volunteers’ skin was also less sensitive to the electric shocks. The same effect was not seen in people who only looked at still images of the polar environment.
Hughes and his colleagues plan further studies of VR to see what kind of dosing regimen works best for pain – such as 30 minutes of VR, four times a day – and if the pain relieving effects would be cumulative or remain only temporary.
“The aim of this study was to show VR has the ability to change the pathological processing associated with chronic pain,” says Hughes. “Using this approach does seem to reduce the overall intensity of the ongoing pain as well as the response we get on the skin. We think there could be changes in the body’s pain relief system’s which can affect how pain sensitivity is processed in the spinal cord.
“There are still many things to figure out, but one exciting aspect of our study is that the VR design we used is completely passive – meaning patients don’t need to use their arms. Potentially, it could mean that patients who are bed-bound or can't move their limbs, but with chronic pain, could still benefit from this approach.”
Previous studies have found that VR can make small improvements in the pain of hospitalized patients recovering from surgery or suffering from neurological, orthopedic, gastrointestinal or cancer pain.