Editing Ganglion

{{Short description|Clusters of neurons in the peripheral nervous system}}
{{About|neuron clusters}}
{{Redirect|Ganglia}}
{{Infobox anatomy
| Name        = Ganglion
| Latin       = ganglion
| Image       = Ganglion high mag.jpg
| Caption     = [[Micrograph]] of a ganglion. [[H&E stain]].
| System      = [[Nervous system]]
}}
[[File:DRG Chicken e7.jpg|thumb|right|A dorsal root ganglion (DRG) from a chicken embryo (around stage of day 7) after incubation overnight in NGF growth medium stained with anti-neurofilament antibody. Note the axons growing out of the ganglion.]]

A '''ganglion''' ({{plural form}}: '''ganglia''') is a group of [[neuron cell body|neuron cell bodies]] in the [[peripheral nervous system]]. In the [[somatic nervous system]], this includes [[Dorsal root ganglion|dorsal root ganglia]] and [[Trigeminal ganglion|trigeminal ganglia]] among a few others. In the [[autonomic nervous system]], there are both [[Sympathetic ganglion|sympathetic]] and [[Parasympathetic ganglion|parasympathetic ganglia]] which contain the cell bodies of postganglionic sympathetic and parasympathetic neurons respectively.

A '''pseudoganglion''' looks like a ganglion, but only has nerve fibers and has no nerve cell bodies.

==Structure==
Ganglia are primarily made up of [[Soma (biology)|somata]] and [[dendrite|dendritic structures]], which are bundled or connected. Ganglia often interconnect with other ganglia to form a complex system of ganglia known as a [[Nerve plexus|plexus]]. Ganglia provide relay points and intermediary connections between different neurological structures in the body, such as the [[peripheral nervous system|peripheral]] and [[central nervous system|central]] nervous systems.

Among vertebrates there are three major groups of ganglia:
* [[Dorsal root ganglion|Dorsal root ganglia]] (also known as the spinal ganglia) contain the cell bodies of [[Afferent nerve|sensory (afferent)]] [[neurons]].
* [[Cranial nerve ganglia]] contain the cell bodies of cranial nerve neurons.
* [[Autonomic ganglion|Autonomic ganglia]] contain the cell bodies of [[autonomic nervous system|autonomic]] nerves.

In the autonomic nervous system, fibers from the [[central nervous system]] to the ganglia are known as [[preganglionic fiber]]s, while those from the ganglia to the effector organ are called [[postganglionic fiber]]s.

===Basal ganglia===
The term "ganglion" refers to the [[peripheral nervous system]].<ref name="titleUNSW Embryology- Glossary G">{{cite web|url=http://embryology.med.unsw.edu.au/Notes/Index/G.htm |website=UNSW Embryology |title=Glossary G |access-date=2008-01-13 |url-status=dead |archive-url=https://web.archive.org/web/20071214053205/http://embryology.med.unsw.edu.au/Notes/Index/G.htm |archive-date=14 December 2007 }}</ref>

However, in the brain (part of the [[central nervous system]]), the [[basal ganglia]] are a group of [[nucleus (neuroanatomy)|nuclei]] interconnected with the [[cerebral cortex]], [[thalamus]], and [[brainstem]], associated with a variety of functions: motor control, cognition, emotions, and learning.{{cn|date=April 2023}}

Partly due to this ambiguity, the ''[[Terminologia Anatomica]]'' recommends using the term 'basal nuclei' instead of 'basal ganglia'; however, this usage has not been generally adopted.{{cn|date=April 2023}}

===Pseudoganglion===
A pseudoganglion is a localized thickening of the main part or trunk of a nerve that has the appearance of a ganglion<ref>{{cite web|title=pseudoganglion|url=http://medical-dictionary.thefreedictionary.com/pseudoganglion|website=[[The Free Dictionary]]|access-date=19 December 2016}}</ref> but has only nerve fibers and no nerve cell bodies.

Pseudoganglia are found in the [[teres minor muscle]]<ref name=pmid13475146>{{cite journal |last=Gitlin |first=G. |date=Oct 1957 |title=Concerning the gangliform enlargement (pseudoganglion) on the nerve to the teres minor muscle |journal=Journal of Anatomy |pmid=13475146 |pmc=1244902 |volume=91 |issue=4 |pages=466–70}}</ref> and [[radial nerve]].{{citation needed|date=February 2014}}

==See also==
* [[Sympathetic ganglion]]
* [[Ganglion cyst]]
* [[Nervous system]]
* [[Neuron]]
* [[Chiasm (anatomy)|Chiasm]]

==References==
{{Reflist}}

==External links==
* {{Commonscat-inline|Ganglia}}

{{Nervous tissue |state=}}
{{Authority control}}

[[Category:Neurohistology]]