Understanding Mechanisms of Normal and Disordered Defecation

Contractions will be recorded with a balloon inserted into the rectum and inflated

Rectum will be filled with a small amount of paste.Two thin catheters will be inserted into the anus to measure pressures and electrical activity (electromyography or EMG). Subjects will be asked to sit on a commode, contract (squeeze) your anal muscles, blow into a balloon, and expel the paste into the commode.