Editing Basal ganglia (section)

==History==
The acceptance that the basal ganglia system constitutes one major cerebral system took time to arise.  The first [[anatomy|anatomical]] identification of distinct subcortical structures was published by [[Thomas Willis]] in 1664.<ref>Andrew Gilies, ''[http://www.anc.ed.ac.uk/~anaru/research/history/ A brief history of the basal ganglia] {{webarchive |url=https://web.archive.org/web/20050130092911/http://www.anc.ed.ac.uk/~anaru/research/history/ |date=30 January 2005 }}'', retrieved on 27 June 2005</ref> For many years, the term [[striatum|corpus striatum]]<ref>Vieussens (1685){{Verify source|needs more bibliographic info|date=December 2010}}</ref> was used to describe a large group of subcortical elements, some of which were later discovered to be functionally unrelated.<ref>{{cite journal | vauthors = Percheron G, Fénelon G, Leroux-Hugon V, Fève A | title = [History of the basal ganglia system. Slow development of a major cerebral system] | journal = Revue Neurologique | volume = 150 | issue = 8–9 | pages = 543–554 | year = 1994 | pmid = 7754290 }}</ref> For many years, the [[putamen]] and the [[caudate nucleus]] were not associated with each other. Instead, the putamen was associated with the [[pallidum]] in what was called the [[Lentiform nucleus|nucleus lenticularis]] or [[Lentiform nucleus|nucleus lentiformis]].

A thorough reconsideration by [[Cécile Vogt-Mugnier|Cécile]] and [[Oskar Vogt]] (1941) simplified the description of the basal ganglia by proposing the term [[striatum]] to describe the group of structures consisting of the caudate nucleus, the putamen, and the mass linking them [[anatomical terms of location|ventrally]], the [[nucleus accumbens]].  The striatum was named on the basis of the striated (striped) appearance created by radiating dense bundles of striato-pallido-nigral [[axons]], described by anatomist [[Samuel Alexander Kinnier Wilson]] (1912) as "pencil-like".

The anatomical link of the striatum with its primary targets, the [[pallidum]] and the [[substantia nigra]], was discovered later. The name ''[[globus pallidus]]'' was attributed by Déjerine to [[Karl Friedrich Burdach|Burdach]] (1822). For this, the Vogts proposed the simpler "[[pallidum]]".  The term "locus niger" was introduced by [[Félix Vicq-d'Azyr]] as ''tache noire'' in (1786), though that structure has since become known as the substantia nigra, due to contributions by [[Samuel Thomas von Sömmering|Von Sömmering]] in 1788. The structural similarity between the [[substantia nigra]] and [[globus pallidus]] was noted by Mirto in 1896. Together, the two are known as the pallidonigral ensemble, which represents the core of the basal ganglia. Altogether, the main structures of the basal ganglia are linked to each other by the striato-pallido-nigral bundle, which passes through the [[pallidum]], crosses the [[internal capsule]] as the "comb bundle of Edinger", and finally reaches the [[substantia nigra]].

Additional structures that later became associated with the basal ganglia are the "body of Luys" (1865) (nucleus of Luys on the figure) or [[subthalamic nucleus]], whose lesion was known to produce movement disorders. More recently, other areas such as the [[centromedian nucleus]] and the [[pedunculopontine complex]] have been thought to be regulators of the basal ganglia.

Near the beginning of the 20th century, the basal ganglia system was first associated with motor functions, as lesions of these areas would often result in disordered movement in humans ([[chorea]], [[athetosis]], [[Parkinson's disease]]).

===Terminology===
The nomenclature of the basal ganglia system and its components has always been problematic. Early anatomists, seeing the macroscopic anatomical structure but knowing nothing of the cellular architecture or neurochemistry, grouped together components that are now believed to have distinct functions (such as the internal and external segments of the globus pallidus), and gave distinct names to components that are now thought to be functionally parts of a single structure (such as the caudate nucleus and putamen).

The term "basal" comes from the fact that most of its elements are located in the basal part of the forebrain. The term [[ganglion|ganglia]] is a misnomer: In modern usage, neural clusters are called "ganglia" only in the [[peripheral nervous system]]; in the [[central nervous system]] they are called "nuclei". For this reason, the basal ganglia are also occasionally known as the "basal nuclei".<ref>{{cite book| vauthors = Soltanzadeh A |title= Neurologic Disorders|isbn=978-964-6088-03-0|publisher=Jafari|year=2004|location=Tehran}}{{Page needed|date=December 2010}}</ref> [[Terminologia anatomica]] (1998), the international authority for anatomical naming, retained "nuclei basales", but this is not commonly used.

The International Basal Ganglia Society (IBAGS)<ref>{{cite book| vauthors = Percheron G, McKenzie JS, Féger J |title=The Basal Ganglia IV: New Ideas and Data on Structure and Function|url=https://books.google.com/books?id=eoblBwAAQBAJ&pg=PR4|publisher=Springer Science & Business Media|language=en|date=6 December 2012|isbn=9781461304852|access-date=26 May 2020|archive-date=26 July 2020|archive-url=https://web.archive.org/web/20200726161411/https://books.google.com/books?id=eoblBwAAQBAJ&pg=PR4|url-status=live}}</ref> informally considers the basal ganglia to be made up of the [[striatum]], the pallidum (with two nuclei), the [[substantia nigra]] (with its two distinct parts), and the [[subthalamic nucleus]], whereas Terminologia anatomica excludes the last two. Some neurologists have included the [[centromedian nucleus]] of the thalamus as part of the basal ganglia,<ref name="Percheron1991">{{cite journal | vauthors = Percheron G, Filion M | title = Parallel processing in the basal ganglia: up to a point | journal = Trends in Neurosciences | volume = 14 | issue = 2 | pages = 55–59 | date = February 1991 | pmid = 1708537 | doi = 10.1016/0166-2236(91)90020-U | s2cid = 36913210 }}</ref><ref>{{cite journal | vauthors = Parent M, Parent A | title = Single-axon tracing and three-dimensional reconstruction of centre median-parafascicular thalamic neurons in primates | journal = The Journal of Comparative Neurology | volume = 481 | issue = 1 | pages = 127–144 | date = January 2005 | pmid = 15558721 | doi = 10.1002/cne.20348 | s2cid = 23126474 }}</ref> and some have also included the [[pedunculopontine nucleus]].<ref>{{cite journal | vauthors = Mena-Segovia J, Bolam JP, Magill PJ | title = Pedunculopontine nucleus and basal ganglia: distant relatives or part of the same family? | journal = Trends in Neurosciences | volume = 27 | issue = 10 | pages = 585–588 | date = October 2004 | pmid = 15374668 | doi = 10.1016/j.tins.2004.07.009 | s2cid = 505225 }}</ref>