Autonomic Nervous System

The autonomic nervous system regulates the internal activities of the body - blood circulation, breathing, digestion. It is involuntary because its activity does not depend on our will, and acts in coordination with the peripheral, or voluntary, nervous system. The autonomic nervous system begins in the ganglia, or large collections of neurons, located on either side of the spine and operates through two divisions: the sympathetic and the parasympathetic.

The sympathetic department of the autonomic nervous system performs the task of activating the activity of the body organs and stimulating various reactions in emergency situations or in cases of high energy consumption: increases metabolism, increases blood supply to the brain, dilates the bronchi and pupils, increases sweating and heartbeat, raises blood pressure through compression arteries, stimulates the adrenal glands.

The parasympathetic division of the autonomic nervous system performs the opposite, inhibitory function: the body uses this nervous system in a state of rest and relaxation, since it saves energy. It takes part in digestion, so after eating you feel drowsy. The parasympathetic nervous system slows the heartbeat, constricts the airways, lowers blood pressure, increases secretions from the nasal, salivary and lacrimal glands, and increases peristaltic movements and intestinal secretions.