For years pain scientists have been perplexed by questions such as, "Ever noticed a bruise that you have absolutely no recollection of getting? Ever taken a shower at the end of a long day in the sun and found the normally pleasantly warm water, painfully hot?"

According to Lorimer Moseley, professor of clinical neurosciences and chair in physiotherapy at University of South Australia, understanding the theory that inaccurate knowledge of chronic pain increases chronic pain, pain scientists now recommend physicians rethink how they provide information to patients.  

New information now proposes how an individual react to pains is based off of the knowledge he or she may have regarding that particular injury.

According to The International Association for the Study of Pain, pain is usually triggered by the messages that are sent from the tissues of the body when those tissues are presented with something potentially dangerous.  Neurons that transport those messages are called nociceptors.

Pain scientists have observed that for the brain to respond to pain it first has to ask "how dangerous is this really?" Through that question the brain gathers information from prior knowledge, experiences, cultural influences and other sensory cues, in order to react to pain.

According to the study if we have a phrase such as a "slipped disc" embedded in our brain, it is held by a network of brain cells, which can be called a "slipped disc" neurotag. Along with the slipped disc neurotag it is likely there is a neurotag for back pain. 

So if one activates the slipped disc neurotag, then one increases the likelihood of activating the back pain neurotag.  Using this model, scientist believes thinking that we have a slipped disc increases the possibility of one having back pain. What if our knowledge about a particular pain is wrong? When the brain produces information regarding a particular pain and if the individual has images associated with that pain, then one's pain increases. Pain scientists believe this is called self-perpetuating pain.

When pain arises the nociception system becomes more sensitive which means in the example of the slipped disc, the spinal cord sends danger signals to the brain overestimating the true level of danger. So when pain exists, individuals believe that tissue damage persists.