The following article is a brief introductrion to the nervous system.
The nervous system can be divided into structurally and functionally:
- Structurally, it is divided into the following two components:
- The central nervous system or CNS (the brain and spinal cord)
- The peripheral nervous system or PNS (spinal and peripheral nerves, and ganglia)
- Functionally, it is divided into the following two components:
- Somatic nervous system or SNS
- Autonomic nervous system or ANS
The two basic directions of communication in the nervous system are:
- Afferent (sensory) nerves or fibers — towards the CNS
- Efferent (motor) nerves or fibers — towards the effector organs (muscles, glands)
An easy way to remember them is that afferent = arrive, and efferent = exit.
The sensory and motor nerves participate in both autonomic and somatic nervous systems.