Public release date: 8-Jan-2008
UCLA researchers found that women with IBS cannot effectively turn-off a pain modulation mechanism in the brain, which causes them to be more sensitive to abdominal pain, compared to women without IBS.
The findings, appearing in the January 9 issue of the Journal of Neuroscience, may lead to a greater understanding of irritable bowel syndrome and new treatment approaches.
Irritable bowel syndrome affects 10 to 15 percent of the U.S. population and causes discomfort in the abdomen, along with diarrhea and/or constipation. Currently there is no cure and treatments only lessen symptoms.
During anticipation of pain, subjects without IBS decreased activity within brain areas involved with pain and emotional arousal, including the insula, amygdala and brainstem. IBS patients could not deactivate these circuits effectively, although they also knew the pain was not dangerous.
“The abdominal hypersensitivity that is a hallmark of IBS may represent an inability to downregulate pain and emotional arousal circuits, said Steven Berman, lead study author and a senior research scientist at UCLA. “IBS patients may have an inability to inhibit the competing tendency to upregulate emotional arousal in order to escape pain faster.”