Perceptions Of Pain Intensity Associated With Grey Matter In Brain: Study

How intensely you feel pain may have something to do with how your brain is structured, according to a new study.

Researchers from Wake Forest Baptist Medical Center found that people with less grey matter in certain brain regions are more likely to report higher intensity of pain in a pain sensitivity test, compared with people with more grey matter in those regions.

The findings, published in the journal Pain, included 116 healthy people who underwent sensitivity tests that involved having a part of their arm or leg heated to 120 degrees Fahrenheit. There were asked to rate their pain intensity, and then after the test, researchers conducted MRI brain scans on them.

The people who rated higher pain intensity had less grey matter in the posterior cingulate cortex, parts of the posterior parietal cortex and the precuneus. These brain regions are known to "contribute to internal thoughts and control of attention," study researcher Nichole Emerson, who is a graduate student at the university, said in a statement.

Specifically, the posterior parietal cortex is known to be involved in our ability to pay attention -- suggesting that ability to focus attention could play a role in perception of pain.

In addition, the posterior cingulate cortex and precuneus are known to be some bar regions that are part of the "default mode network," which is associated with daydreaming and free-flowing thoughts. Therefore, "default mode activity may compete with brain activity that generates an experience of pain, such that individuals with high default mode activity would have reduced sensitivity to pain," study researcher Robert Coghill, Ph.D., a professor of neurobiology and anatomy at the university, noted in the statement.