Ganglion

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Micrograph of a ganglion. H&E stain.
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.

In anatomy, a ganglion (/ˈɡæŋɡliən/ GANG-glee-ən; plural ganglia) is a nerve cell cluster[1] or a group of nerve cell bodies outside of the central nervous system.[2][3] Cells found in a ganglion are called ganglion cells, though this term is also sometimes used to refer specifically to retinal ganglion cells.

Neurology[edit]

In neurological contexts, ganglia are composed mainly of somata and dendritic structures which are bundled or connected. Ganglia often interconnect with other ganglia to form a complex system of ganglia known as a plexus. Ganglia provide relay points and intermediary connections between different neurological structures in the body, such as the peripheral and central nervous systems.

Among vertebrates there are three major groups of ganglia:

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

Basal ganglia[edit]

The term "ganglion" refers to the peripheral nervous system.[4]

However, in the brain (part of the central nervous system), the "basal ganglia" is a group of nuclei interconnected with the cerebral cortex, thalamus and brainstem, associated with a variety of functions: motor control, cognition, emotions, and learning.

Partly due to this ambiguity, the Terminologia Anatomica recommends using the term basal nuclei instead of basal ganglia.

See also[edit]

References[edit]

  1. ^ Sadava, David; Heller, H. Craig; Orians, Gordon H.; Purves, William K.; Hillis, David M. (2008). Life: The Science of Biology (8th ed.). W. H. Freeman. p. 943. ISBN 9780716776710. 
  2. ^ "ganglion" at Dorland's Medical Dictionary
  3. ^ Brodal, Per (2010). The Central Nervous System. Oxford University Press. ISBN 9780195381153. 
  4. ^ "UNSW Embryology- Glossary G". Retrieved 2008-01-13. [dead link]