Central nervous system (CNS)
Central nervous system (CNS)
The central nervous system (CNS) is part of the nervous
system which also consists of the peripheral nervous system (PNS).
It is called “central” because it processes information of the whole body and
is therefore the “central” coordinator and control authority. It is
protected from outside influences (like mechanical impact or temperature) by
three layers called “meninges”: The dura mater (outside layer), the
arachnoid mater (middle layer) and the pia mater (inside layer). Another
protective mechanism is the blood-cerebral barrier, which prevents
contaminants from entering the brain or the spinal cord.
![](https://moodle.ruhr-uni-bochum.de/pluginfile.php/2575557/mod_glossary/entry/42539/Download%20%281%29.png)
The CNS structurally consists of the brain and
the spinal cord and cell-wise of neurons (grey
matter) and their axons (white matter).
Its main functions are the following:
- Integration of inside- and outside stimuli
- Motor coordination
- Regulation of vital processes (movement, sleep
etc.)
- Cognitive functions (language, emotions,
consciousness, memory and attention)
The CNS interacts with its counterpart, the PNS
(everything outside the brain and spinal cord). The PNS gives sensory
information to the CNS (“afference”) and the CNS then gives motor
instructions back to the PNS ("efference"). Also, the PNS is
often subdivided into smaller functions (like autonomous and the somatic NS).
There are also neurological diseases that especially
concern the CNS. Some examples are:
- Parkinson disease
- Alzheimer
- Meningitis
Sources and further links: