This is a fascinating article with excellent sources.
The past two centuries have produced a cascade of life-altering advances in medicine, yet we have been unable to deal with one seemingly straightforward condition: chronic pain. It affects 1 in 5 people around the world, yet in large part because of a fundamental misunderstanding of its basic nature, it remains poorly treated.
Our failure to understand pain is most clearly exemplified in the opioid epidemic. While opioid medications are effective in treating patients with acute pain, such as the type one develops after breaking a limb, the cumulative evidence suggests that they are no better at helping patients with chronic pain — generally defined as pain that lasts for six months or more — than safer painkillers such as ibuprofen or acetaminophen.
Prescription opioid use skyrocketed in part because of a now-discredited public health campaign that sought to position all pain as a purely physical sensation, a “vital sign” similar to one’s heart rate or blood pressure. Yet research studies are revealing that acute pain may have little in common with chronic pain. If you study the brain using MRI scans or other techniques, these studies show, the phenomenon that chronic pain appears most similar to is memory, and the condition with the most parallels to chronic pain is post-traumatic stress disorder (PTSD).
Pain and memory
The relationship between pain and memory is incredibly close, as many studies have shown, and for good reason. Evolutionarily speaking, pain’s chief purpose is to keep us safe from harm, and to achieve that, it has evolved into an effective teacher. No matter how many times I warn against it, it is only after my daughter touches the hot skillet once that she learns to never do it again.
Because humans are some of the longest-living animals, we need to be able to remember how we got hurt for a very long time. And because our bodies would much rather we be overcautious, our recollections of agony are often exaggerated.
This memory phenomenon, called the peak-end rule, says that we tend to remember an experience through its most emotionally intense points and its end. When it comes to chronic pain, that means the more pain a person lives with, the more likely they are to misremember it as being worse than it was. Even if infrequent, pain’s worst spikes are embedded much more deeply than moments of relative respite; thus our recollection is skewed negatively.