autonomic nervous system

autonomic nervous system (ANS) Part of the body's nervous system that regulates the body's involuntary functions. It helps to regulate the body's internal environment by controlling the rate of heart beat, peristalsis (movements of food through the digestive tract) and sweating. This system is also part of an individual's emotional response, such as blushing and a quickened heartbeat. See also homeostasis; involuntary muscle

autonomic nervous system The part of the nervous system which controls involuntary activities such as homoeostasis. The autonomic nervous system is regulated by the hypothalamus and comprises two antagonistic parts, the parasympathetic and sympathetic nervous systems. See also CENTRAL NERVOUS SYSTEM; PERIPHERAL NERVOUS SYSTEM.

autonomic nervous system (ANS) The part of the vertebrate peripheral nervous system that supplies stimulation via motor nerves to the smooth and cardiac muscles (the involuntary muscles) and to the glands of the body. It is divided into the parasympathetic and the sympathetic nervous systems, which tend to work antagonistically on the same organs (see illustration). The activity of the ANS is controlled principally by the medulla oblongata and hypothalamus of the brain.