Chronic pain in the brain
In a recent study Mackey 2014 of 94 people, half without pain issues and half with chronic lower back pain, analysis of the data was able to predict the individual with pain 76% of the time.
Areas of the brains of individuals with lower back pain have less dense gray matter in the amygdala (memory and emotions) and more dense gray matter in the cerebellum (sensory) and the prefrotnal cortex (movement planning and abstract reasoning). Unfortunately, it is not known whether these differences help cause the pain OR if the pain causes these differences; but there does seem to exist an association. It’s also unclear whether the pain is related to a decrease in certain areas, an increase in excitability in some areas, or both.
As these questions are answered, treatments may be able to be devised that stimulate or de-stimulate certain areas of the brain.
Is chronic pain associated with similar brain findings despite where it occurs? For instance what does a TMD patient’s brain look like? Would this analysis give similar results if done on TMD patients? I emailed Sean Mackey to get his thoughts.
As with any research it is wise to scrutinize the results. My only question would be does this accuracy hold up if you are given a random sampling of people. This sample was known to contain 50% of those with pain and perhaps that factored in as an issue.
Neuroimmunomodulation and treatment of chronic pain
Really the only chronic pain we deal with is chronic TMD. There have be a plethora of creative “solutions” in dealing with this condition, nearly all are only temporary fixes. To learn more about chronic TMD, it’s causes and it’s treatments one must look at how chronic pain in the body works. The study linked here is interesting because it links the neruo system and the immune system through control and application of the inflammation processes that occur within our bodies. They discovered a previously unknown cholinergic anti-inflammatory pathway.
Turns out stimulation of the vagus nerve may control a wide range of previously very difficult condition to control. Severe depression and epilepsy are 2 conditions that have been successfully treated so far.
A systemic review of low dose naltrexone, .1-4.5 mg of the anti-inflammatory immunomodulator, has shown pain reduction for chronic pain. Hatfield JADA 2020