Pain and the Brain: Is It All In Our Heads Part 2
Last week I introduced the idea that the brain and the body are constantly interacting. Changes in our mental and emotional health can impact our physical health. Changes in physical health can impact how we feel mentally and emotionally. One interesting example of this mind-body connection is pain.
We’ve all experienced pain before. From small daily pains like stubbing your toe or bumping in to a table with your hip, to more noticeable pain like breaking a bone. Our body is constantly processing signals from our environment and perception of pain is one of those signals.
Our experience of pain is a combination of neurological (brain) and psychological (mind) factors. At a basic level, there are specialized nerve endings called nociceptors in our tissues (e.g. skin, organs, bones, and joints) that are alerted when there is damage to the tissue that our brain perceives as pain. For example if you place your hand on a hot stove these nociceptors will perceive the damaged tissue and send the signal alerting your brain to danger. The signals travel from the site of the injury to your spinal cord, then up to your brain.
There are many parts of the brain involved in processing pain including sensory areas of the brain (to identify where the pain is in your body), motor areas of the brain (to respond to the pain), and the areas of the brain that process emotion and memory. Because these higher cortical areas involved in memory, emotion, and complex thought are involved in experiencing pain, our past experiences will impact our perception of pain. For example if you have touched a hot stove before and felt pain, the next time you see a hot stove you are going to react faster and maybe even before you touch the stove because your brain has learned to avoid the stove and the associated pain.
Touching a hot surface is an example of acute pain. Our brain is really efficient at reacting to acute pain so that we get away from the source of the pain (take our hand off the stove) and start to heal. This type of acute pain reaction is our brain’s response to danger and helps us survive.
Another type of pain is chronic pain. Chronic pain is pain that lasts beyond normal injury recovery time. For example say I fall and sprain my knee. The sprain heals in 6-8 weeks, but six months later I still have pain. The injury has healed but my brain is still reacting as if I am experiencing acute pain. This pain is an example of chronic pain. Sometimes the original cause of the chronic pain is known like in this example but often it is not. Chronic pain can develop gradually over time such as chronic back pain, or chronic headaches.
Like I said from an evolutionary perspective pain is beneficial. It helps us avoid danger and protect our bodies. However, in chronic pain this normal brain response goes awry. Because pain is partly a learned process, sometimes our brains can overreact to situations and interpret pain as more severe or more dangerous than it should be. Rather than becoming less bothered by pain over time as the injury heals, individuals prone to chronic pain can become very alert for pain, they start to avoid activities that will trigger the pain, and this results in the brain becoming less tolerant and less able to cope with pain. Just like my example from last week of the individual who starts avoiding bright lights because they are aggravating, individuals who start avoiding situations that might cause pain lose physical and mental tolerance/stamina/strength to tolerate pain. I feel pain, so I stop the activity that causes pain, so my body and my brain have less strength and tolerance to cope with pain, so next time I go into the situation my brain is going to perceive it as more painful and I will further limit my activities. Think about if you had broken your arm and it had to be in a cast for several months. When I take my cast off my arm is going to be weak. When I start using the arm again it is going to hurt because my muscles are weak. If I avoid exercising my arm, it’s going to get even weaker over time, and I’m going to be in even more pain when I try and use it again. This is how chronic pain can develop.
So why do some people have more tolerance for pain? When a pain signal reaches the brain it passes through brain regions involved in emotion, decision-making, and physical sensation. How we react to pain is determined by a number of individual factors. In this way pain is all in your head because it’s impacted by her past experiences and her brains perception.
Psychological factors impact our perception of pain. We know that chronic stress, anxiety, low mood, and poor sleep can increase perceived pain. We feel pain as more severe when we are stressed. Experiences we had in childhood or throughout our lives can also impact how we perceive pain. For example, if our family members struggle with pain management we are more likely to struggle with managing pain. As well if we’ve had past negative experiences in situations associated with pain we are more likely to have a stronger pain reaction. For instance if you’ve had a bad experience at the dentist before with lots of pain even a minor dental procedure can be perceived as more painful. Again, our brain learns to react to situations that might cause discomfort or pain from our past experiences.
The good news is we have many strategies that can help us retrain our brains to have higher tolerance for pain. Again it can be helpful to think of the brain like a muscle. We slowly increase our exposure to activities that cause pain and our brain learns that it can handle situations, the pain is not a signal of something horribly wrong with our body, and over time our brains get stronger at managing pain. Think back to my example of elite athletes last week. While we can’t all be professional athletes, we can develop mental strength like an athlete to help manage pain. I would encourage you to check out the Canadian Psychological Association fact sheet on chronic pain for more information.
There are also some strategies that can trick our brain into managing acute pain better. Here are some strategies for helping with acute pain:
Rub the area - If you stub your toe or bump into your desk, rub the area. This will help the pain go away faster. According to gate control theory of pain by rubbing the area around where the injury occurred we stimulate the nerve fibers that recognize touch and this inhibits the pain receptors. So the pain becomes less intense.
Swear like a sailor - Next time you stub your toe let the profanities fly. Research suggests that uttering curse words helps with acute pain management. This is because of how pain signals pass through the parts of brain that are involved in preventing us from doing socially inappropriate things (like swearing). You have to use profanities though, just yelling random words doesn’t work.
Distract yourself - Another option to manage pain is distraction. If we are able to find another task we like doing it helps manage pain.
Remember pain is an experience that combines the mind and the body. This means that we can learn to have more control over our pain and improve our quality of life.