GI Motility Testing: A Laboratory and Office Handbook

Henry P. Parkman, MD; Richard W. McCallum, MD, FACP, FRACP (Aust), FACG; Satish SC Rao, MD, PhD, FRCP (Lon)

Chapter 26: Functional Brain Imaging In Gi Neurophysiology (continued)

Howard R. Mertz, MD

Abnormal sensory processing appears to play a key role in generation of symptoms in disorders such as noncardiac chest pain, functional dyspepsia, and irritable bowel syndrome (IBS) for which symptoms may in part be due to visceral hypersensitivity.1 Distension causes pain or discomfort at lower thresholds in functional patients than in control subjects. Furthermore, such stimulation generally reproduces clinical symptoms. These painful sensations are thought to ascend from the gut to the brain via a system of nerves termed the brain-gut axis2 (Figure