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Updated: May 24, 2026
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Spatiotemporal Mapping of Motility in Ex Vivo Preparations of the Intestines
Published on: January 27, 2016
The physiology of human defecation.
Somnath Palit1, Peter J Lunniss, S Mark Scott
1Academic Surgical Unit (GI Physiology Unit), Barts and the London School of Medicine and Dentistry, Blizard Institute, Queen Mary University, London, UK. s.palit@qmul.ac.uk
Digestive Diseases and Sciences
|February 28, 2012
Summary
Human defecation is a complex process involving coordinated neural activities and anatomical structures. Understanding normal defecation is key to treating constipation and fecal incontinence.
Area of Science:
- Neurogastroenterology
- Physiology
- Pelvic Floor Disorders
Background:
- Defecation is a complex sensorimotor function.
- It involves integrated neural control from the central, spinal, peripheral, and enteric nervous systems.
- The gastrointestinal tract, pelvic floor, and anal sphincters are critical anatomical components.
Purpose of the Study:
- To detail the current understanding of normal human defecation.
- To highlight recent advances in the field.
- To identify gaps in knowledge and areas lacking consensus regarding defecation physiology.
Main Methods:
- Review of current scientific literature on human defecation.
- Analysis of integrated sensorimotor functions.
- Description of four distinct physiological phases of defecation.
Main Results:
- Normal defecation relies on coordinated neural activities and intact anatomy.
- Four distinct temporal and physiological phases characterize the defecation process.
- Recent advances have improved understanding, but knowledge gaps persist.
Conclusions:
- A thorough understanding of normal defecation physiology is essential.
- This knowledge is fundamental for effective treatment of constipation and fecal incontinence.
- Further research is needed to address existing knowledge gaps and achieve consensus.
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