Image / Ion Chiosea
Pain exists to encourage protective behaviors, and the brain’s perceived need for protection depends on factors beyond the current health of our tissues. While pain may not always be a signal of tissue damage, it is always a signal from the brain that an area or a movement or a behavior is in need of protection, alteration or cessation. Thus, contrary to our old popular (and fairly intuitive) understanding, pain is an output of the brain, not an input. Always.
“Pain is an action signal, not a damage meter.”
– Lorimer Moseley, Painful Yarns p. 34
The brain creates pain as a request (or a clear demand) that we avoid threat. Threats come in many flavors: physical, psychological, emotional, and social. Pain is a bio-psycho-social phenomenon. How the brain assesses threat varies, both from person to person and at different times for the same person. It’s a complex evaluation that may include: our present and past physical health; our general level of stress or ease; past experiences; our perception of our own resilience; our actual or perceived level of support (social, financial, etc.); our beliefs about our own bodies, about healing, and about the world; and our understanding of what is happening to or within our bodies. That’s an incomplete list of considerations, but you get the idea – our brain’s perception of threat arises out of a composite of factors. And all this transpires rapidly, below our conscious awareness. While taking in a great deal of information from various systems of the body, the brain is always trying to answer the question “how dangerous is this really?”, and the answer in large part determines: a) whether the brain elects to issue pain signals, and b) how strong those signals should be.
For example, let’s say two people bend over to pick something up and both feel some pain. In the forward bend, a small degree of mechanical damage was sustained, which triggered danger receptors (or, nociceptors) in the lower backs of both people. These nociceptors deliver danger reports to both brains. Let’s see how two brains may handle the same situation differently:
Person A has had a fair amount of back pain in the past, and the internal map of her back is very fuzzy. In fact, the brain isn’t really sure what’s happening on the back side of her body, and this contributes to a sense of threat. Prior to this incident, she’s been worrying a lot about finances and feeling troubled about her future. Additionally, two years ago she sustained injury to her lower back that began in just this way, and disabled her for several weeks. It was very painful, she was unable to work for two months, and even caring for herself was out of the question for nearly 10 days. When she was diagnosed, her doctor used the term “slipped disc” to describe her condition, and she now tends to envision her spine as weak and unstable. The pain medication prescribed to her back then did little to relieve her pain but greatly aggravated her digestive system. Thoughts of incapacitation, being a burden on others, and experiencing unremitting pain for weeks flash though her mind, all feeding into a growing sense of threat.
Person B is active and enjoys good balance, and has never had any noticeable pain in her back, nor any negative experiences with doctors, diagnosis or severe pain or pain medication. She has enjoyed a healthy, pain-free existence and expects to, and she believes her body to be very strong and resilient. She also has excellent health insurance, financial resources, and social support. All of this feeds into her brain’s assessment of how dangerous her situation is likely to be.
Person A and Person B had the exact same experience, mechanically speaking. But their experience in every other way will likely differ, and they’re unlikely to have a similar pain experience in response to the exact same stimulus. When these two brains sought to answer the question ‘how dangerous is this, really?’, the information each received painted very different pictures of what this injury could ultimately mean.
At this point, we have an idea of the function of pain, and some of the factors that affect the brain’s determination of threat. In future posts, we’ll look at how the pain alarm system works within the nervous system, or how these danger signals arise before they make it to the brain. We'll also look at some ways to use meditation and observation to help ourselves navigate pain situations. Until then, breathe deeply, practice often, and be well.
Dana Wyss Healing Arts