According to new research the brains of those who suffer from irritable bowel syndrome are more sensitive to pain than those of healthy people.
Irritable bowel syndrome (IBS) is the most commonly diagnosed gastrointestinal condition across the developed world. Exactly what causes it remains a mystery since no tissue damage or infection is typically found in patients. A number of different factors are thought to play a role in IBS but patients are often left feeling like the condition is all in their head and treatment results are patchy at best.
Now, new research has shed more light on one possible trigger for IBS. The research in fact does point to the condition being in patient's heads, but not in the sense that they need to see a psychiatrist.
The study which was conducted at the University of California, Los Angeles (UCLA) and published in the Journal of Neuroscience reveals that certain regions of the brain are much more active in IBS patients than healthy individuals when the person is experiencing pain.
The researchers, led by Steven Berman exposed women with and without IBS to predictable, mildly painful abdominal pain and then looked at how various areas of their brains responded using functional MRI scans.
In healthy people the brain has the ability to partially suppress the pain response when the person has prior warning of a painful stimulus or when a short-term increase in pain will lead to lasting benefit such as removing foreign material from a wound.
In this study, Berman and colleagues found that when healthy women were warned before being given a painful stimulus their MRIs showed their brains damping down the pain response. In contrast, MRIs of the women with IBS revealed that areas of the brain involved with pain perception remained highly active.
The results suggest that part of what is going on in IBS is due to patients handling pain differently to healthy people. The study doesn't reveal whether the pain is due to normal gut sensations being perceived as pain or whether genuine pain stimuli in the gut are being amplified.
IBS patients are often dismissed as suffering from purely phychological problems due to a high degree of co-existing depression and anxiety. The areas of the brain seen to remain active in this study were the insula, amygdala and brainstem, all of which are associated with pain, as well as emotion. The findings also therefore represent a biological explanation for this connection between IBS and emotional disorders.