Rhombencephalon 2412117 217385495 2008-06-05T20:22:33Z Ccolen 7254237 {{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}} {{neuroanatomy-stub}} {{Rhombencephalon}} {{Cerebellum}} [[Category:Neuroanatomy]] [[Category:Brainstem]] [[Category:Central nervous system]] [[Category:Cranial nerves]] [[Category:Developmental biology]] [[de:Rhombencephalon]] [[es:Rombencéfalo]] [[it:Rombencefalo]] [[nl:Rhombencephalon]] [[ru:Задний мозг]]