Working in Movement

Researchers in the UK are working with the idea of tricking some chronic pain out of being so, well, chronic. For some people who experience chronic pain, there is no clearly demonstrable cause, no easy-to-recognize acute injury or illness, and hence, little in the way of "cure" that can be offered. Instead, the research looks into a new theory of what causes this tricky sort of pain that resists traditional diagnosis.

This theory points to the brain as the source of the pain. More precisely, it's the brains image of the body. If this image somehow becomes distorted, this distortion can cause the brains movement control systems and its sensory systems to get out of synch. And it's this mismatch that can cause the experience of pain during hand or foot movement.

In a news release from the University of Bath, Mirrors can trick the brain into recovering from persistent pain, research suggests, researcher Dr. Candy McCabe describes how it works:

We think it is the same system that is triggered when you are running down stairs, miss the last step and then feel a jolt of surprise. In missing that bottom step, you jar the prediction that your brain had made about what was going to happen, triggering an alert to the body that things are not as you expected, hence the feeling of surprise. This is because in most cases normal awareness and experience of our limbs is often based on the predicted state rather than the actual state. When the two do not match we think sensations are generated to alert the body that things are not as it thought rather like an early warning mechanism. If the discrepancy is very large [like in the mirror experiment described below] then pain may be experienced, as pain is the bodys ultimate warning mechanism. Somehow the brain's image of the body differs from what it senses. When the patient moves their hand, foot or limb, they experience pain as a result.

The research investigated the possibility of improving the accuracy of the brain image by using mirrors to trick the brain. Patients with complex regional pain syndrome exercised in front of a mirror. Researchers found that more than half experienced pain relief during and after the exercise.

By using a mirror reflection of a normal limb to convince the brain that everything is alright, we have found that we can correct this imbalance and help alleviate pain in complex regional pain syndrome,Ã[infinity]âo[ring]Ã[not equal]Â[caron] said Dr Candy McCabe who works in the University of Bath's School for Health and the RNHRD.