What is CPM?
CPM, Conditioned Pain Modulation, is one of our neural system mechanisms to control pain. CPM is an endogenous descending pain inhibition mechanism, located in the brain stem, the most “primitive” part of the brain, which is a critical area for nociception and pain processing.
In essence, pain is the brain’s way of notifying that there is a problem, danger, a threat that has to be escaped from or eliminated, etc. The brain stem is capable of “deciding” that a certain painful stimulus is not essential and does not represent a real threat. This “decision” results with the increased released of certain substances – neurotransmitters – that flow down the neural system and are capable of aborting the pain by blocking the nociceptive messages from propagating up the neural system.
CPM is an endogenous mechanism, but in many people suffering from certain neurological diseases it is deficient and is not “triggered” when it should have.