Editing Hippocampus (section)

== Name ==
[[File:Hippocampus and seahorse cropped.JPG|thumb|right|The human hippocampus and [[Fornix of the brain|fornix]] (left) compared with a [[seahorse]] (right)<ref>Preparation by László Seress in 1980.</ref>]]

The earliest description of the ridge running along the floor of the [[Lateral ventricles#Inferior horn|inferior horn]] of the [[lateral ventricle]] comes from the Venetian anatomist [[Julius Caesar Aranzi]] (1587), who likened it first to a [[Bombyx mori|silkworm]] and then to a [[seahorse]] ([[Latin language|Latin]] ''hippocampus'', from [[Ancient Greek|Greek]] ἱππόκαμπος, from ἵππος, 'horse' + κάμπος, 'sea monster').<ref name="Tatu">{{cite journal |vauthors=Tatu L, Bogousslavsky J |title=Beasts and Gods: Hippocampal quarrels before memory |journal=Rev Neurol (Paris) |volume=178 |issue=10 |pages=991–995 |date=December 2022 |pmid=35927101 |doi=10.1016/j.neurol.2022.03.022 |url=}}</ref> The German anatomist Duvernoy (1729), the first to illustrate the structure, also wavered between "seahorse" and "silkworm". "Ram's horn" was proposed by the Danish anatomist [[Jacob B. Winslow|Jacob Winsløw]] in 1732; and a decade later his fellow Parisian, the surgeon de Garengeot, used ''cornu Ammonis'' – horn of [[Amun]],<ref name="Duv05">{{cite book | vauthors = Duvernoy HM | title = The Human Hippocampus | edition = 3rd | year = 2005 | publisher = Springer-Verlag | location = Berlin | isbn = 978-3-540-23191-2 | page = 1 | chapter = Introduction | chapter-url = https://books.google.com/books?id=5GkpPjk5z1IC&pg=PP1 | ref = refDuvernoy2005 | access-date = 2016-03-05 | archive-date = 2016-08-28 | archive-url = https://web.archive.org/web/20160828091605/https://books.google.com/books?id=5GkpPjk5z1IC&pg=PP1 | url-status = live }}</ref> after the ancient Egyptian god who was often represented as having a ram's head.<ref name="Neurologia2014">{{cite journal |last1=Iniesta |first1=I. |title=On the origin of Ammon's horn |journal=Neurología (English Edition) |date=October 2014 |volume=29 |issue=8 |pages=490–496 |doi=10.1016/j.nrleng.2012.03.024}}</ref> ''Ammon'' is the Greek name for Amun.<ref name="autogenerated1">{{cite journal | vauthors = Pearce JM | title = Ammon's horn and the hippocampus | journal = Journal of Neurology, Neurosurgery, and Psychiatry | volume = 71 | issue = 3 | pages = 351 | date = September 2001 | pmid = 11511709 | pmc = 1737533 | doi = 10.1136/jnnp.71.3.351 | ref = refPearce2001 | department = Historical Note }}</ref>

The head region of the hippocampus is enlarged, and presents two or three rounded elevations or foot-like digitations, and hence it was named the '''pes hippocampi''' (''pes'' meaning ''foot'').<ref>{{cite web|title=BrainInfo|url=http://braininfo.rprc.washington.edu/centraldirectory.aspx?ID=2283|website=braininfo.rprc.washington.edu}}</ref><ref name="Anand">{{cite journal |vauthors=Anand KS, Dhikav V |title=Hippocampus in health and disease: An overview |journal=Ann Indian Acad Neurol |volume=15 |issue=4 |pages=239–46 |date=October 2012 |pmid=23349586 |pmc=3548359 |doi=10.4103/0972-2327.104323 |doi-access=free |url=}}</ref> Later this part was described as ''pes hippocampi major'', with an adjacent bulge in the [[Lateral ventricles#Structure|occipital horn of the lateral ventricle]], described as ''pes hippocampi minor'' later renamed as the [[calcar avis]].<ref name="Duv05" /><ref>{{cite journal | vauthors = Owen CM, Howard A, Binder DK | title = Hippocampus minor, calcar avis, and the Huxley-Owen debate | journal = Neurosurgery | volume = 65 | issue = 6 | pages = 1098–1104; discussion 1104–1105 | date = December 2009 | pmid = 19934969 | doi = 10.1227/01.neu.0000359535.84445.0b | s2cid = 19663125 }}</ref> In 1786 [[Félix Vicq-d'Azyr]] published an authoritative description naming just the ''hippocampus'' but the term remained largely unused with no description of any function proposed until in the middle of the 20th century it was associated with memory.<ref name="Tatu" />

[[Johann Christoph Andreas Mayer|Mayer]] mistakenly used the term [[hippopotamus]] in 1779, and was followed by some other authors until [[Karl Friedrich Burdach]] resolved this error in 1829. In 1861 the hippocampus minor became the center of a dispute over [[human evolution]] between [[Thomas Henry Huxley]] and [[Richard Owen]], satirized as the [[Great Hippocampus Question]]. The term hippocampus minor fell from use in anatomy textbooks and was officially removed in the [[Nomina Anatomica]] of 1895.<ref>{{cite journal | vauthors = Gross CG | title = Hippocampus minor and man's place in nature: a case study in the social construction of neuroanatomy | journal = Hippocampus | volume = 3 | issue = 4 | pages = 403–415 | date = October 1993 | pmid = 8269033 | doi = 10.1002/hipo.450030403 | ref = refGross1993 | s2cid = 15172043 }}
</ref> Today, the structure is just called the hippocampus, with the term ''cornu Ammonis'' (that is, 'Ammon's horn')  surviving in the names of the [[hippocampal subfields]] CA1–CA4.<ref name="Pang">{{cite journal | vauthors = Pang CC, Kiecker C, O'Brien JT, Noble W, Chang RC | title = Ammon's Horn 2 (CA2) of the Hippocampus: A Long-Known Region with a New Potential Role in Neurodegeneration | journal = The Neuroscientist | volume = 25 | issue = 2 | pages = 167–180 | date = April 2019 | pmid = 29865938 | doi = 10.1177/1073858418778747 | s2cid = 46929253 | url = https://kclpure.kcl.ac.uk/portal/en/publications/0547351a-ef50-44ac-b15d-e192706f446b }}</ref><ref name="Oxford">{{cite web |title=Search Results for ammon's horn |url=https://www.oxfordreference.com/search?q=ammon%27s+horn&searchBtn=Search&isQuickSearch=true |website=Oxford Reference |access-date=9 December 2021}}</ref><ref name="Colman">{{cite web | vauthors = Colman AM |title=dentate gyrus |url=https://www.oxfordreference.com/view/10.1093/acref/9780199657681.001.0001/acref-9780199657681-e-2184?rskey=auIwwd&result=10 |website=A Dictionary of Psychology |publisher=Oxford University Press |access-date=10 December 2021 |language=en |doi=10.1093/acref/9780199657681.001.0001 |date=21 May 2015|isbn=978-0-19-965768-1 }}</ref>