Physiology of Defecation

  • Rauf A. Wani
  • Natasha Thakur


Defecation is a reflex provoked through a sacral arc by distention of the rectum. In infancy, the evacuation of the rectum occurs reflexly. The development of the control over defecation reflex is associated with the growth of inhibition over it. The cerebral cortex cannot only inhibit the reflex but can also initiate it when suitable circumstances are available for voiding. Thus, continence is an acquired capacity to suppress the natural urge to defecate. When this capacity is impaired, incontinence occurs.


Pelvic Floor Anal Canal Pelvic Floor Muscle External Anal Sphincter External Sphincter 
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Copyright information

© Springer India 2016

Authors and Affiliations

  1. 1.Department of Colorectal SurgerySheri Kashmir Institute of Medical SciencesSrinagarIndia
  2. 2.Department of General and Minimal Invasive SurgerySherikashmir Institute of Medical Sciences Medical CollegeSrinagarIndia

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