Pain and the Brain

In my last blog entry, we took some time to explore and discuss chronic pain. We went over what defines pain as “chronic” in nature and touched on some of the reasons we may feel pain long after an injury has healed. We ended our discussion by touching on the complexity of chronic pain conditions and we shed some light on the brain’s influence in how an individual experiences pain. This blog will delve deeper into how the brain controls our pain experience. We will also begin exploring factors that affect our pain levels and will start a look into ways in which we can control these factors to better manage our overall pain experience. As we know, dealing with pain can be a complicated and demoralizing experience. Chronic pain in particular is a multifaceted condition, and a result of much more than the initial injury that set it off. When trying to understand chronic pain and why people experience it, we need to explore the brain’s role in pain perception. We discussed the fact that before pain can be “felt”; there is intricate communication between the body’s tissues, pain receptors, nerves, and brain. Pain signals are sent to the brain via these pathways, are interpreted and evaluated, and sent back to the injured tissue. It was initially thought that this communication between the body’s tissues, nerves, and brain was a one way street. In fact, we have come to learn that these pathways are more of a two-lane highway; the messages sent up to the brain, are also influenced by messages coming down from the brain. In essence, we have learned that the brain has the ability to act like a “gate”, controlling the messages that are both received and sent out from it. The “Gate Control Theory of Pain” asserts that certain factors can have the ability to “close the gates” to painful input, preventing pain sensations from travelling to the central nervous system and on to the brain for interpretation. These “factors” can be both physical and/or psychological in nature, and can greatly influence the amount of pain one endures following an injury. A good example of this occurs in sports, when an athlete sustains a serious injury during a big game. With emotions running high, adrenaline pumping, and the noise of the crowd deafening any chance of coherent thought, the athlete plays on. In this example, the input associated with a “usually” painful injury is being muffled or snuffed out by the factors explained above. In other words, when the athlete’s mind is occupied and focused on the game at hand, they likely will not feel how painful the injury actually is. It is only later, after the game is over (and the adrenaline wears off), that the athlete discovers how painful the injury really is. These factors and distractions are essentially “closing the gate”, stopping the pain signals from being sent to the brain for interpretation. The Gate Control Theory of Pain” also acknowledges the fact that the brain can actually stop or inhibit pain signals being sent down to different parts of the body as well. This, again, helps us to explain why some people experience less pain during the day, when they are distracted by other events going around them, but then notice their pain much more during the night when there is little to no activity taking place. Now you may be thinking, if things such as distraction or heightened emotions can “block” pain signals from being felt, what other factors may be beneficial in reducing pain levels? Are there factors I can control and use in my day-to-day pain management? What are some of the factors that could make my pain worse? We will take time in our next blog instalment to explore these topics further. We will also begin to discuss the long term effect of pain on an individual, and how our brain and nervous system react to prolonged periods of chronic pain.