Autonomic nervous system

division of the peripheral nervous system

The autonomic nervous system (ANS) controls the conditions inside the body. It is sometimes called the 'visceral nervous system' or 'involuntary nervous system'. The ANS is part of the peripheral nervous system.

The autonomic nervous system
Blue = parasympathetic
Red = sympathetic

ANS controls all automatic actions. That means that it controls all reflexes and actions during sleep.

Most of its activities are done without the person having conscious control over them. The person usually cannot feel what the ANS is doing. However, some of the ANS's activities work together with the conscious mind, like breathing.

The ANS controls many different things, like heart rate, digestion, respiration rate, salivation, perspiration, diameter of the pupils, the discharge of urine, and erection.

There are two different sections within the ANS:

Other websites


Further reading

  • Michael D. Gershon 1998. The second brain. HarperCollins, New York.