Urology & Urogynecology > Education and Reference

Regulatory / Sensory Loop Landmarks

The MOTOR CORTEX is a social ON/OFF SWITCH. The pontine micturition center performs cerebral, conscious control of the lower urinary tract (“potty training”).  It serves an inhibitory function and is responsible for the inactivation of the micturition reflex.

A lesion in the micturition center (organic brain disease, injury, and stroke) causes loss of voluntary control, but the micturition reflex (reflex loop) remains intact, so the patient is incontinent (“reflex voiding”). Disruption of the ascending sensory pathway causes incontinence, if the motor pathway is intact. There is no sensation of fullness so voiding occurs spontaneously. Disruption of the descending regulatory (motor) pathway causes retention. If the sensory pathway is intact, there may be a sense of fullness, but voiding cannot be initiated. Interesting point:  The pontine micturition center is under the influence of the limbic system and is affected by emotions, which explains physiologic frequency when under stress. This is important to remember when doing urodynamics (stressor) and attempting to elicit sensation and capacity from the study.

Sectional References

Lecture by George Webster, MD at Life-Tech seminar: Clinical Urodynamic    Workshop. Schafer W, Abrams P, et al, Good Urodynamic Practices: Uroflowmetry, Filling Cystometry, and Pressure-Flow Studies. Wiley-Liss, Inc. 2002 Abrams P, et al, The Standardization of Terminology of Lower Urinary Tract Function: Report from the Standardisation Sub-committee of the    International Continence Society. Abrams P, Blaivas JG, and Stanton SL, et al:  The Standardization of Terminology of Lower Urinary Tract Function. Scand J Urol Nephrol, Supplelmentum 114, 1988. Burgio K, Pearce K, Lucco A: Staying Dry.  Baltimore:  Johns Hopkins University Press, 1989 Chalker R, Whitmore K, Overcoming Bladder Disorders.  New York: Harper Perennial, 1990, pp 62 – 63. Nitti  V (ed), Practical Urodynamics.  Philadelphia:  W B Saunders Company, 1998. Ostergard D, Bent A, ed:  Urogynecology and Urodynamics, Theory and Practice.    Baltimore:  Williams & Wilkins, 1989, pp 258-259. Lecture  by Kathy Davis, RN at seminar:  Quest for Excellence in continence Care, Emory University School of Medicine, 1997 O’Donnell P, Urinary Incontinence.  St. Louis: Mosby, 1997, Chapter 62, pp 440—441. Lecture by Anne Weber, MD and Pat Clouse, PT , Bladder Training and Behavioral Modification,  at the Cleveland Clinic Foundation:  Advances in Female Voiding Dysfunction and Pelvic Disorders, 3/16/96 Karlowicz K, ed:  Urologic Nursing, Principals & Practice.  Philadelphia:   Saunders, 1995, p. 51. Consortium for Spinal Cord Medicine, Acute Management of Autonomic Dysreflexia, Paralyzed Veterans of America, Feb 1997.

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