Scientists Say Brain ‘Hot Wired’ for Chronic Pain

Scientists Say Brain ‘Hot Wired’ for Chronic Pain

People suffering from chronic pain hate to hear it, but the pain may really be “all in your head” according to a new study funded by the National Institutes of Health.

The research, published in the journal Pain, found that irregularities in the brain may predict whether a person will suffer chronic lower back pain. Scientists say it’s a discovery that may ultimately lead to changes in the way patients are diagnosed and treated.

The red dots represent differences in white matter (green in this image) that can predict who will suffer from chronic low back pain. Image courtesy of Feinberg School of Medicine.

The red dots represent differences in white matter (green in this image) that can predict who will suffer from chronic low back pain. Image courtesy of Feinberg School of Medicine.

“We’ve found the pain is triggered by these irregularities in the brain,” said A. Vania Apkarian, a senior author of the study and a professor of physiology at Northwestern University’s Feinberg School of Medicine.  “We’ve shown abnormalities in brain structure connections may be enough to push someone to develop chronic pain once they have an injury.”

Using MRI brain scans of people who had a lower back injury, scientists found they could predict with about 85% accuracy which patients’ pain would persist.

“We were surprised how robust the results were and amazed at how well the brain scans predicted persistence of low back pain. Prediction is the name of the game for treating chronic pain,” Apkarian said.

The predictor was a specific irregularity or marker the scientists identified in the axons, pathways in the brain’s white matter that connect brain cells so they can communicate with each other.

Apkarian and his colleagues scanned the brains of 46 people who had an episode of lower back pain for at least four weeks and had not experienced any pain for at least one year before that.

Over the course of the next year, they evaluated the patients’ pain with examinations and questionnaires. About half of the subjects recovered at some time during the year, but the other half continued to have pain, which the researchers categorized as persistent.

The scientists found a consistent difference in white matter between the subjects who recovered and those who experienced pain throughout the year.

The researchers also found that the white matter of subjects who had persistent pain looked similar to a third group of subjects known to suffer from chronic pain. In contrast, the white matter of the subjects who recovered looked similar to that of healthy control subjects.

The abnormalities identified in the study were found in two brain regions involved in processing emotion and pain.

“The abnormality makes them vulnerable and predisposes them to enhanced emotional learning that then amplifies the pain and makes it more emotionally significant,” Apkarian said.

He explained more about his findings in this interview:

Low back pain represents about 28% of all types of pain in the United States. About 23% of these patients suffer chronic, or long-term, low back pain.

“Currently we know very little about why some patients suffer chronic low back pain,” said Debra Babcock, MD, a program director at the National Institute of Neurological Disorders and Stroke.

“The earlier we detect pain will become chronic, the better we may be able to treat patients.”

Authored by: Richard Lenti

There are 11 comments for this article
  1. John Quintner at 8:37 am

    @ Dave. Could you please explain what you mean by “adaptive” research? What are your suggestions for future research topics in the area of Pain? How will you ensure the involvement of people in pain in such research?

  2. dave at 6:07 pm

    The researchers have failed to do adaptive research and involve people in pain as to what research they believe might help. In addition research is largely aligned with the interests of pharmaceutical companies and device manufacturers. Science is for sale at NIH and researchers at NIH, just wish to do more biomedical research and not results oriented research. Look whose on advisory councils at NIH-MD’s and Ph.Ds-and what do they do-they only ensure their interests and occupational strategies are considered. Research at NIH for pain is capitalistic and not humanistic and the interests of people in pain is not represented.

  3. John Quintner at 9:53 pm

    @ Melisa. I am not against research. However, all to commonly researchers (and clinicians) try to reduce the lived experience that we call pain to a material “thing” that can be the cause of structural changes in the nervous system. The attempt to classify chronic pain as being a disease in its own right is another example of such muddled thinking. Pain is not a “thing” but is not “no-thing”!

    You ask “What do we do with the people who are suffering?” Doing things to such people has been a monumental failure of biomedicine. We need to teach these people that the discovery that our nervous systems have the property of plasticity means that all experiences, including pain, are modifiable.

  4. Melisa at 5:55 pm

    Okay….so meanwhile? What do we do with the people that are suffering?
    Whether it’s in their heads or real pain!
    So in the future they will give everyone an MRI to see if they will suffer from “make believe” chronic pain in the future?

    Thanks John Quintner for your comments…right on!

  5. dave at 11:28 am

    Researchers in pain remind me of the Battle of the Bulge-when colonel Hesslers second in command asks him why the Germans were still fighting the war when the knew they couldn’t win Hessler responding by saying they just wanted to keep wearing the uniform. Researchers want to keep doing research in pain care-they aren’t winning the war on pain. The pain experts in the IOMs June 2011 on pain care in America indicated clearly that they don’t believe in cures for pain- but Sean Mackey sure got a lot of money for research shortly after he completed his role on the IOM Committee- and isn’t dr. Mackey a leading proponent of brain research for pain. I rest my case.

  6. Joy H Selak at 9:38 am

    I found it a great relief when I learned of this connection, it made sense and I was able to connect the dots that led to my condition.
    Knowledge is good!

  7. John Quintner at 9:00 am

    Furthermore, in their pursuit of a structural explanation of chronic back pain, it seems to me that the authors of this paper have failed to appreciate that the lived experience that we call pain is created on a moment to moment basis by our brains. Otherwise, why would they talk about “a physiological state reflecting the brain’s response to back pain”?

    Their use of the term “chronification” when describing an obscure physiological process (a change in “brain functional connectivity”) whereby acute pain undergoes a transition to chronic pain should not be allowed to pass without comment. What exactly do they mean by this?

    My overall impression of this paper is that the authors lack both the theory and language necessary to make any sense of the MRI findings in their study.

    I may be missing the point but I cannot see how these findings are likely to change the way patients are diagnosed and treated.

  8. dave at 6:37 am

    Dr Apkarian has falledn pray to neurocentrism and mistakes appearances for reality. But it is commonplace for researchers and experts in pain care to mistake appearances for reality. And since medical science as failed to find reliable biomarkers for pain they know seek to blame pain on brain dysfunction. The dysfunction in pain is the chronic misdirection in pain care-that has lead to ever rising prevalence of painful conditions like arthritis and neuropathic pain with a medical profession constantly bragging about how much they understand pain mechanisms. The reality is that the experts in pain care truly know so little and live in a state of denial about the realities of pain. Lets not forget 85% of back pain is still considered of unknown origin- so much for the experts in pain care.

  9. John Quintner at 9:44 pm

    Thanks Pat. Their paper contains the following nonsensical statement on page 2167: “More importantly, in light of (the) current study, brain white matter abnormalities reported in diverse chronic pain conditions should be considered as evidence for structural predisposition for developing these specific chronic pain conditions.” Another circular argument?

  10. Pat Anson, Editor at 7:58 pm

    John, that is an accurate quote. We agree the meaning is rather obtuse.

  11. John Quintner at 7:42 pm

    @ Richard. The following quote does not make any sense to me – “The abnormality makes them vulnerable and predisposes them to emotional learning that then amplifies the pain and makes it more emotionally significant.” Seems like a circular argument to me.