myelencephalon

1. The posterior portion of the embryonic hindbrain, from which the medulla oblongata develops.
2. The medulla oblongata of the adult brain.

The posterior portion of the embryonic hindbrain, from which the medulla oblongata develops.

1. the part of the central nervous system comprising the medulla oblongata and caudal of the fourth ventricle.
2. the posterior of the two brain vesicles formed by specialization of the rhombencephalon in the developing embryo.

The noun has one meaning:

Meaning #1: the posterior part of the hindbrain in developing vertebrates; forms the medulla oblongata in adults

Brain: Myelencephalon
Diagram depicting the main subdivisions of the embryonic vertebrate brain. These regions will later differentiate into forebrain, midbrain and hindbrain structures.
Gray's	subject #187 767
NeuroNames	hier-695
MeSH	Myelencephalon

The myelencephalon is a developmental categorization of a portion of the central nervous system. The myelencephalon is composed of the medulla oblongata; contains a portion of the fourth ventricle; as well as 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).

Developing from the hindbrain, a structure present in all vertebrate embryos, the myelencephalon is differentiated from the 5 metencephalon at the age of approximately weeks, and develops mainly into the medulla oblongata. Evolutionarily, this area of the brain is the most ancestral, controlling visceral (autonomic and homeostatic) mechanisms such as breathing, heart and blood vessel activity, digestions, and peristalsis (forward and reverse).

This neuroscience article is a stub. You can help Wikipedia by expanding it. v • d • e

v • d • e Human brain: rhombencephalon, myelencephalon: medulla (TA A14.1.04, GA 9.767) Dorsal Surface Posterior median sulcus · Posterolateral sulcus · Area postrema · Vagal trigone · Hypoglossal trigone · Medial eminence Grey: Cranial nuclei afferent: GVA: VII,IX,X: Solitary/tract/Dorsal respiratory group · SVA: Gustatory nucleus efferent: GSE: XII  · GVE: IX,X,XI: Ambiguus · SVE: X: Dorsal · IX: Inferior salivatory nucleus Grey: other Gracile nucleus · Cuneate nucleus (Accessory cuneate nucleus) White: Sensory/ascending Sensory decussation  · Medial lemniscus · Inferior cerebellar peduncle (Juxtarestiform body) · Ascending dorsal longitudinal fasciculus · MLF, III, IV and VI White: Motor/descending Descending dorsal longitudinal fasciculus · MLF, III, IV and VI Ventral White: Motor/descending Motor decussation · Olivocerebellar tract · Rubro-olivary tract Grey matter Ventral respiratory group · Arcuate nucleus of medulla · Inferior olivary nucleus Surface Anterior median fissure · Antero-lateral sulcus · Olive · Pyramid Grey: Raphe/ reticular Reticular formation (Gigantocellular, Parvocellular, Ventral, Lateral, Paramedian) · Raphe nuclei (Obscurus, Magnus, Pallidus)

v • d • e Ventricular system, rhombencephalon, met- and myel-: fourth ventricle (TA A14.1.05.701-726, GA 9.797) Roof (dorsal) rostral: Superior medullary velum (Frenulum) caudal: Inferior medullary velum · Taenia of fourth ventricle Floor/rhomboid fossa (ventral) rostral (pons): Facial colliculus · Locus coeruleus caudal (medulla}: Vagal trigone · Hypoglossal trigone · Area postrema · Obex Medial eminence · Sulcus limitans Apertures Median/Magendie · Lateral recess to Lateral/Luschka Other Tela chorioidea of fourth ventricle · Fastigium

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