They scanned the brains of 26 patients with chronic back pain and 26 healthy people.
The patients with chronic pain caused by damage to the nervous system showed shrinks in the brain by as much as 11% - equivalent to the amount of gray matter that is lost in 10-20 years of normal aging.
The decrease in volume, in the prefrontal cortex and the thalamus of the brain, was related to the duration of pain.
Every year of pain appeared to decrease gray matter by 1.3 cubic centimetres.
Is the loss related to inactivity, or to pain itself? Is it related to neuronal depletion in the spinal cords (mentioned in article) or to persistent high cortisol levels (known to cause neuron depletion)? Why is the brain so vulnerable to pain or stress anyway? Doesn't seem to make any evolutionary sense. Does the brain injury somehow perpetuate the inactivity/pain cycle -- making the condition untreatable? What can we do to change the dynamic of chronic pain development? Is the pain the primary cause, or have we discovered an unrecognized primary neurologic disorder that has, as one of its correlates, a predisposition to chronic pain syndromes? Does this neuronal loss affect cognition, or is it primarily related to perception, sensation and movement?
And those are just the truly obvious questions.
We know that chronic pain, especially when associated with disability, is very, very hard to treat. The burden on families is staggering. The economic cost is awesome. The suffering of afflicted seems never ending.
We're just beginning to understand what's going on.