Some Brains are hardwired for Chronic Pain, Scientists Say

Sharon Moore September 23, 2013

Tweet

The structure of the brain may predict whether a person will suffer from low back pain, a new study found. Their findings support the growing claim that the brain plays a big role in chronic pain, a concept that may change how doctors treat patients.

Nearly 8 million people in the UK suffer from chronic pain, most particularly low back pain, according to the British Pain Society. Majority of them wait for an average of 6 years for a diagnosis and three more years for a treatment. Furthermore, almost 10 million Britons suffer from pain almost every day, resulting in a major impact on their work and quality of life. 

Scientists have long believed that the cause of low back pain may be found at the site of the injury, but a growing body of research suggests that the brain may be more involved.

Some brains are hardwired for chronic pain

Researchers at the National Institute of Neurological Disorders and Stroke (NINDS), a division of the National Institutes of Health in the US, suggest that the brain is hardwired for chronic pain. Their studyinvolved measuring the structure of white matter and the nerve cell wires or axons, which connect brain cells in different parts of the brain – using the diffusion tensor imaging (DTI) technology. 46 people who had low back pain for about three months before being treated in the hospital but had not experienced pain at least in the previous year, were recruited to undergo the DTI scan.

Other than the brain scans, the researchers also evaluated the pain as experienced by the subjects using their doctors’ examinations and questionnaires four times during the study period. At the end of the study, half of the participants recovered at some time within the year and the rest had pain throughout, which the researchers categorised as “persistent”.

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

"We may have found an anatomical marker for chronic pain in the brain," said Vania Apkarian, Ph.D., a senior author of the study and professor of physiology at Northwestern University Feinberg School of Medicine in Chicago.

They also found that the white matter of the patients who had persistent pain looked similar to a third group of subjects known to suffer from chronic pain. On the other hand, the white matter of those who recovered looked similar to that of healthy people. The white matter brain scans predicted at least 80% of the outcomes.

In particular, the nucleus accumbens and the medial prefrontal cortex are involved in pain, the researchers note. According to Dr Apkarian, understanding these networks will help doctors diagnose chronic pain better and develop more precise treatments.

Their work was published in the journal Pain.

Source of this article:

Brain white matter structural properties predict transition to chronic pain