Does Acupuncture Therapy Alter Activation of Neural Pathway for Pain Perception in Irritable Bowel Syndrome?: A Comparative Study of True and Sham Acupuncture Using Functional Magnetic Resonance Imaging

Patients with irritable bowel syndrome (IBS) are characterized by abnormal central processing with altered brain activation in re-sponse to visceral nociceptive signals. The effect of electroacupuncture (EA) on IBS patients is unclear. The study is set to study the effect of EA on brain activation during noxious rectal distension in IBS patients using a randomized sham-controlled model. Methods Thirty IBS-diarrhea patients were randomized to true electroacupuncture or sham acupuncture. Functional MRI was performed to evaluate cerebral activation at the following time points: (1) baseline when there was rectal distension only, (2) rectal dis-tension during application of EA, (3) rectal distension after cessation of EA and (4) EA alone with no rectal distension. Group comparison was made under each condition using SPM5 program. Results Rectal distension induced significant activation of the anterior cingulated cortex, prefrontal cortex, thalamus, temporal regions and cerebellum at baseline. During and immediately after EA, increased cerebral activation from baseline was observed in the anterior cingulated cortex, bilateral prefrontal cortex, thalamus, temporal regions and right insula in both groups. However