Lorimer Moseley, Prince of Wales Medical Research Institute, University of New South Wales, Australia

Pain is a protective system, activation of protective networks occurs in response to threat.  Pain is an output of the brain just like movement is an output of the brain.  There are a lot of things that can regulate these outputs.

Pain is evoked when input reaches the brain.  When the network is activated pain emerges in that network.  Beliefs are represented by networks in the brain, then that network is activated that belief is activated.  Knowledge and logic, other sensory cues area, social context, the list goes on….. are also activated in the same way.  These are represented in the brain by a network of cells which has the ability to activate the ‘pain tag’.

The brain will correct any error it perceives to exist.  It will modulate input from the spinal cord with descending control (which can be inhibitory or facilitatory).  The capacity to modulate is profound!

Graded motor imagery training (implicit and explicit) can reduce pain.   Lorimer talked about studies with CRPS patients where the brain was trained to reduce the output of pain.  The studies trained the brain through these consecutive steps:

1. implicit motor imagery (left/right judgement task – recognising left or right hand on computer)
2. explicit motor imagery (imagined pain free limb movements)
3. mirror movements (adopt posture with hands shown on computer but watch mirror image of good hand)

Tactile training treatment is the progression that targets primary sensory cortex inhibition.  It has been proven to  decrease the pain response in patients with CRPS. This can also be improved by the subject receiving tactile training whilst looking at the arm.  What would happen if we employed this approach (looking at the painful area) with all our chronic pain patients?

Lorimer’s talk was fascinating and i really did struggle to keep up…. I’ll ask Lorimer to add some comment, watch this space!