The University of Oxford researchers used a novel imaging technique to determine how different levels of pain affected the brain of 17 volunteers, and noticed that dorsal posterior insula matched reports of all participants related to pain intensity.
The same method could be used in other areas for determining pain level in people who cannot easily provide a description of their pain, such as those in a coma, small children or dementia patients, said study authors.
“We have identified the brain area likely to be responsible for the core, ‘it hurts’, experience of pain,” researcher Irene Tracey said in a university news release.
In the study, Tracey and her team rubbed a cream containing the chemical capsaicin — the compound in chili peppers that causes a burning sensation — onto the legs of 17 healthy volunteers. The researchers then placed a hot or cold water bottle against the volunteers’ skin to increase or decrease their pain level, respectively.
Meanwhile, the researchers scanned the participants’ brains and asked them to rate how much pain they felt.
In all patients, dorsal posterior insula glowed more in the brain scans when the volunteers reported the most pain. This finding indicated that region acts as a pain measuring tool, researchers said.
The next step in the study will attempt to “switch off” this brain region for patients with intractable pain.
The findings were published in journal Nature Neuroscience.