Within a few days of injury, scientists can predict which patients will develop chronic pain based on the extent of cross "talk" between two regions of the brain, and the person’s anxiety level after the injury, according to a new Northwestern study.
Today, more than 50 million adults in the U.S. suffer from chronic pain — pain lasting longer than three months — and is the most common reason why people seek medical attention, according to the Centers for Disease Control and Prevention (CDC).
A better grasp of how chronic pain changes the central nervous system has emerged since Woolf’s experiment. A.Vania Apkarian’s pain lab at Northwestern University found that when back pain persists, the activity in the brain shifts from the sensory and motor regions to the areas associated with emotion, which include the amygdala and the hippocampus. "It’s now part of the internal psychology," Apkarian says, "a negative emotional cloud that takes hold."
Imaging technology further validates that psychological and emotional factors spur chronic pain. A. Vania Apkarian, who runs a neuroscience pain lab at Northwestern University, predicted with 85 percent accuracy which subjects would develop chronic pain by looking not at their backs but at their brains.
"If the placebo response is predictable and persistent, it has all the pieces of being an innocuous way of treating these people," says A. Vania Apkarian, a neuroscientist and long-time pain researcher at Northwestern University. "It’d be a cheap way to do it. You don't need thousands and thousands of dollars of pharmaceutical industries' stuff to be put in your body, which always has side effects."
Vania Apkarian, director of the Center for Translational Pain Research at Northwestern University Feinberg School of Medicine, studies which patients respond to placebo. In a 2016 study in the journal PLOS Biology, he used brain scans to identify the regions in the brain that can predict a response to placebo in 56 chronic knee osteoarthritis pain patients compared with 20 control patients. He replicated the findings in a 2018 study in Nature Communications with 63 chronic-back-pain patients.
Chronic pain, such as lower back pain that lasts for months or years, affects 100 million Americans and costs half a trillion dollars a year in healthcare costs. It is also contributing to the current opioid crisis. A. Vania Apkarian, PhD, explains his recent discoveries related to chronic pain and how placebos may be a very effective option for some.