Day of exam, subject will report to the endoscopy unit. At that time, subject will be prepared for examination by doctor who will apply a sensor array to the abdomen with adhesive sleeves. In addition, a waist belt device that holds the data recorder will be fitted to subject. Subjects will swallow the capsule endoscope. The capsule endoscope passes naturally through digestive tract while transmitting video images to the data recorder worn on the belt for approximately eight hours. At this point, subjects will be free to leave the University of Chicago hospital until they return eight hours later for disconnection of the recording equipment.