Basic systems arrangement of the nervous system
Nerves comprise a cell body, or soma (plural = somata), and cell processes/neurites. Dendrites are the processes that receive information, whereas axons/nerve fibres convey efferent information as action potentials/nerve impulses.
The axons may be unmyelinated or myelinated with a lipid-rich, insulating myelin sheath that both speeds up nerve conduction and protects the axon. Ganglia are collections of nerve cell bodies outside the CNS. Nuclei are collections of nerve cell bodies with a similar function, inside the CNS.Nerve fibres are of three basic types:
1. Afferent/sensory fibres bring information into the central nervous system (CNS) from the periphery and convey that information to higher centres for processing.
2. Efferent/motor fibres take information from motor planning centres through the CNS to connect with other motor fibres that take information into the periphery.
3. Integrating fibres that may connect afferent fibres with storage centres, other processing centres or efferent fibres. They process, organise and/or store information.