Rhombencephalon
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{{Infobox Brain|
Name = Rhombencephalon |
GraySubject = 187 |
GrayPage = 767 |
Image = EmbryonicBrain.svg |
Caption = Diagram depicting the main subdivisions of the embryonic vertebrate brain. These regions will later differentiate into [[forebrain]], [[midbrain]] and [[hindbrain]] structures. |
Image2 = Gray682.png |
Caption2 = Superficial dissection of [[brain-stem]]. Lateral view. |
IsPartOf = |
Components = |
Artery = |
Vein = |
BrainInfoType = hier |
BrainInfoNumber = 531 |
MeshName = Rhombencephalon |
MeshNumber = A08.186.211.132.810 |
DorlandsPre = r_12 |
DorlandsSuf = 12709581 |
}}
The '''rhombencephalon''' (or '''hindbrain''') is a [[Morphogenesis|developmental]] categorization of portions of the [[central nervous system]] in [[vertebrates]].
The rhombencephalon can be subdivided in a variable number of transversal swellings called [[rhombomere]]s. In the human embryo we can distinguish eight rhombomeres, from caudal to rostral: Rh7-Rh1 and the [[List of anatomical isthmi| isthmus]] (the most [[Anatomical_terms_of_location|rostral]] rhombomere).
A rare disease of the rhomencephalon, "rhombencephalosynapsis" is characterized by a missing [[vermis]] resulting in a fused cerebellum. Patients generally present with cerebellar ataxia.
The caudal rhombencephalon has been generally considered as the initiation site for neural tube closure.<ref>http://www.springerlink.com/content/f3fc056wde57c1yc/</ref>
==Myelencephalon==
Rhombomeres Rh7-Rh4 form the [[myelencephalon]].
The myelencephalon forms the [[medulla oblongata]] in the adult brain; it contains:
* a portion of the [[fourth ventricle]],
* the [[glossopharyngeal nerve]] (CN IX),
* [[vagus nerve]] (CN X),
* [[accessory nerve]] (CN XI),
* [[hypoglossal nerve]] (CN XII),
* and a portion of the [[vestibulocochlear nerve]] (CN VIII).
==Metencephalon ==
Rhombomeres Rh3-Rh1 form the [[metencephalon]].
The metencephalon is composed of the [[pons]] and the [[cerebellum]]; it contains:
* a portion of the fourth ventricle,
* the [[trigeminal nerve]] (CN V),
* [[abducens nerve]] (CN VI),
* [[facial nerve]] (CN VII),
* and a portion of the [[vestibulocochlear nerve]] (CN VIII).
==Additional images==
<gallery>
Image:Gray18.png|Chick embryo of thirty-three hours’ incubation, viewed from the dorsal aspect. X 30.
Image:Gray40.png|Embryo between eighteen and twenty-one days.
</gallery>
{{Wiktionary}}
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{{Rhombencephalon}}
{{Cerebellum}}
[[Category:Neuroanatomy]]
[[Category:Brainstem]]
[[Category:Central nervous system]]
[[Category:Cranial nerves]]
[[Category:Developmental biology]]
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[[ru:Задний мозг]]