As with other subjective experiences, such as love, fear, or anger, there's no way to objectively measure pain. We asked Sean Mackey, MD, PhD, chief of the Pain Management Division and associate professor of anesthesia at Stanford University School of Medicine, to explain the unpleasant sensation we all feel in different ways.
Pain is such a simple word, but the problem is that what people think it means is not really what it means. All of my patients tend to associate what's going on in their arm or their back as pain out there in the body. But it's not. It's something we call nociception -- electrochemical signals generated in our body in response to injury that get transmitted along nerve fibers to our spinal cord and up to our brain, where they're processed and become the experience of pain.
For example, if you cut your finger, that's not pain in your finger, that's nociception. But nociception is such a terrible word; it doesn't exactly roll off the tongue, and it's not easy for people to remember.
Pain can be an acute event, which signals there is harm and you need to get away from it. Unfortunately, when pain becomes chronic -- when it's present for long periods of time after the tissue has healed -- we can still have this perception of pain even though there is no obvious tissue damage or injury. At that point, pain fundamentally causes rewiring and alterations in our nervous system.
We need to think about pain as a disease in and of its own right -- much like any other chronic disease, such as diabetes, asthma, or heart disease.
2. What are common myths about pain?
One is that it's all in your head. This has some basis in truth, but we have to be careful. Yes, pain is all in our brain, but that doesn't mean it's made up. I spend a lot of time with my patients validating their experience of pain and then helping them understand how pain really is influenced in the brain by a multitude of factors -- stress, anger, catastrophizing, anxiety, belief systems, expectations -- all of these play a significant role in our experience of pain.