Have you ever really thought about phantom limb pain? Perhaps you have not even heard of it? It is defined as pain that is still felt even without the existence of that body part, such as after amputation. Seventy percent of all people who lose a limb experience phantom pain.
How can pain exist in a part of the body that does not? This is quite a thing to get your head around!
In the past months as we have looked more at the brain and its critical role in the pain experience for all humans. Perhaps from your readings, you may have an idea of how phantom limb pain can exist?
As we are discovering, the pain response in us all comes from the brain's split-second decision in deciding whether you are in pain or not- and then to act. On weighing up all information at that exact moment of time, for that individual for that experience, the brain can decide this. You may remember that this information comes from multiple sources – sensory input from the body tissues, memory and mood centres and can depend on your gender, age, and beliefs about pain, etc etc.
So how does this relate to phantom limb pain?
Phantom limb pain can become worse when the person is stressed or anxious. It can be worse when another person comes too near to where the body part once existed. People can still feel rings on fingers that have been lost to an accident. And others report feeling that a leg missing still feels like it is there and carries on walking!
This can all be explained by the existence of the 'virtual body'- maps in the brain's hardware (nerves) that represent the real physical body. The virtual body allows for us to know where our bodies are in space – the feeling, the movement and the 'muscle memory' of our body. If you close your eyes and imaging turning on a tap, you can remember, visualise and almost feel yourself doing it. You can still do this because your brain uses the virtual body to know where the physical body is. (This is like the 'brain movies' we have discussed in earlier months).
With phantom limbs, although the physical limb has been lost, the virtual representation of it still exists in the brain. This is why the limb is still felt as if it were still there and attached.
So how does this illustration of phantom limb pain help us in understanding affect the way we experience pain?
The science and explanations behind phantom limb pain have allowed a clearer understanding of the virtual representation of the real body. We know that the brain is forever adapting and that this can be seen in the virtual body maps too. The virtual body can alter and does so to stimulus. If you have pain in your toe that lingers for days or weeks, the virtual representation or map of the toe in your brain enlarges. It's like your brain has opened up the flood gates for all information to flood from the toe- like an over-sensitivity. This can make the pain experience of your toe 'switch on' very easily.
The good news is that these changes to the virtual body can be reversed too. Maps representing your toe in the brain (as in the above example) can be made smaller as the toe gets better, stronger with normal movement returning. The flood gates can close and the heightened awareness of sensation and pain of your toe disappear.
More on this later.......