Is some pain mainly in the brain?
Chronic pain sufferers maybe overestimating the real-world threat. Virtual reality technology gives promising hope.
One in five Australians aged 45 and over is living with persistent, ongoing pain. This pain can be disabling and stressful, making it hard to work and do other everyday things.
Not that long ago, medical advice for treating pain was to take an aspirin and have lots of rest. Then along came anti-inflammatory drugs and some daring medicos even prescribed low-level movement.
Now, it is common for pain sufferers to manage their symptoms with specialist physio classes and prescribed exercises to build capacity, strength and hopefully confidence.
The development of pain management has followed new discoveries of the brain and how it is a control centre for the pain we feel and the degree we feel it.
As any chronic pain sufferer knows, the first twinges of pain can send them into flight mode where they retreat from any movement whatsoever. That can last for weeks or much longer.
The role of the brain in pain perception has evolved even further.
Neuroscientists from the University of South Australia studied people with chronic back pain, the most common painful condition which costs western countries billions of dollars in lost productivity every year.
They stimulated the painful area and a non-painful area. Their finding was not what most back pain sufferers would have expected. The stimuli were processed more slowly by the brain if they came from the painful area.
Equally surprising, the same effect occurred if the stimuli were delivered to a healthy body part near the painful area.
Lead author of the study, Professor Lorimer Moseley, said in people with chronic pain, there are changes in the way the brain processes information from and about the painful body part.
“What is remarkable is that the problem affects the space around the body as well as the body itself,” he said.
Experiments showed that if a hand was held near the painful area of the back, it was also affected.
Professor Moseley concluded, “Obviously, it is not external space that is distorted but the ability of the brain to represent that space within its neural circuitry.
“This finding opens up a whole new area of research into the way the brain allows us to interact with the world and how this can be disrupted in chronic pain.”
Pain can be a helpful tool to make sure we don’t exceed our limits, but when it persists it can be overprotective and detrimental. In overreacting, our brain responds to pain by changing our perception of the world around us.
Research shows that people experiencing chronic pain see the world as a harsher place – distances are longer and hills are steeper. Pain can make us see the world more hurtful.
A recent University of South Australia found people with knee osteoarthritis view the world as harsher than people without pain. They overestimate hill steepness, with overestimation strongly associated with fear.
The study compared the spatial perception of 50 people with the condition and 50 without it. What was different about this study is that researchers used virtual reality technology.
Participants were asked to estimate steepness – uphill and downhill – and distance. The researchers then explored associations between the participants’ perception and pain intensity and fear.
People with knee osteoarthritis overestimated uphill and downhill steepness compared to pain-free participants. The groups did not differ for distance, but the heightened overestimation, and fear, in people with knee osteoarthritis relative to pain-free controls increased as downhill slopes became steeper.
The researchers concluded that chronic pain may shift perception of the environment in line with protection, with overestimation heightened when threat is greater (steeper hills, more fearful).
The researchers hope further research could see virtual reality technology become part of the treatment of chronic pain by offsetting the patient’s perceptual bias. This could re-enable people to be more mobile and confident, and perhaps feel less pain.
Remember: consult your general practitioner or qualified health professional before undertaking any exercise or treatment regime.
