By Neil Wagner
Researchers at Northwestern University may finally have found the cause of chronic pain, pain that simply will not go away after an injury has healed or long-lasting pain of unknown origin. The cause appears to be excessive signaling between two regions of the brain, the frontal cortex and the nucleus accumbens.
How confident are the researchers in their findings? They were able to predict with 85% accuracy which people with a back injury would ultimately go on to experience episodes of chronic pain and which would not, based on a single brain scan at the study's start.
According to a 2011 report by the Institute of Medicine, there are 100 million chronic pain sufferers in the U.S.
Possibly because chronic pain has proven so difficult to treat, there can be an attitude in the medical community that chronic pain sufferers are malingerers, people who are simply unable to keep a stiff upper lip, cope with the pain and get on with their lives like most people do. Hopefully this study will put an end to that attitude.
Because there has usually been no known source for a patient's chronic pain, most treatments have focused on simply trying to relieve the pain that does occur. Now researchers have a starting point for developing effective therapies that will treat the pain at its source by blocking the brain signals that cause it.
The study followed 40 people who had experienced an episode of back pain for the first time in their lives. Brain scans were conducted on the subjects at the study's start and three more times over the course of a year. Along with increased communication between the frontal cortex and nucleus accumbens, the subjects who ultimately experienced chronic pain also showed a loss in gray matter density.
An article on the study was published online in Nature Neuroscience.
August 3, 2012