Health Encyclopedia

Autonomic Nervous System

Autonomic Nervous System

The autonomic nervous system controls all "automatic" body functions, such as breathing, heart rate, blood pressure, sweating, mouth-watering (salivating), and the movement of food through the intestines (peristalsis).

One part of the autonomic nervous system, called the sympathetic nervous system, reacts when a person is facing a dangerous or frightening situation and will automatically increase the heart rate and breathing and move blood to the muscles.

The other part of the autonomic nervous system, the parasympathetic nervous system, helps the body return to normal after the threat is over. It will automatically lower heart rate and breathing and move blood back to the rest of the body (for example, the digestive system or reproductive system).

The autonomic nervous system differs from the voluntary nervous system, which allows a person to control the muscles and body movements.

Last Revised: December 5, 2012

Author: Healthwise Staff

Medical Review: Anne C. Poinier, MD - Internal Medicine & G. Frederick Wooten, MD - Neurology

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.

© 1995-2013 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.

USNWR 2013-2014Magnet Hospital RecognitionConsumer Choice2014 Best DoctorsJoint Commission Report

Disclaimer: The information on this website is for general informational purposes only and SHOULD NOT be relied upon as a substitute for sound professional medical advice, evaluation or care from your physician or other qualified health care provider.