Douglas A. Drossman, MD: Stress can affect GI function. When you have a lot of GI difficulties, you get emotional distress. The nerve pathways are the same, in fact a lot of the medications that we use can be used in the bowel as well as in the brain. So the connection is there and we basically have to capitalize on that to try to understand these conditions. And all of this you don't see on X-ray or endoscopy. And that in fact creates problems because the patients and sometimes the doctors, don't think it's as real or legitimate because they don't see anything.