Superior medullary velum | |
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Details | |
Identifiers | |
Latin | velum medullare superius |
NeuroNames | 593 |
NeuroLex ID | birnlex_1300 |
TA98 | A14.1.05.007 A14.1.05.719 |
TA2 | 5976 |
FMA | 74508 |
Anatomical terms of neuroanatomy |
The superior medullary velum (anterior medullary velum) is a thin, transparent lamina of white matter [ citation needed ] which - together with the inferior medullary velum - forms the roof of the fourth ventricle. It extends between the two superior cerebellar peduncles. The lingula of cerebellum covers - and adheres to - its dorsal surface. [1]
The superior medullary velum extends between the dorsomedial margins of the two superior cerebellar peduncles. [1] On the dorsal surface of its lower half the folia and lingula are prolonged.
It forms, together with the superior cerebellar peduncle,[ contradictory ] the roof of the upper part of the fourth ventricle; it is narrow above, where it passes beneath the facial colliculi, and broader below, where it is continuous with the white substance of the superior vermis.
A slightly elevated ridge, the frenulum veli, descends upon its upper part from between the inferior colliculi, and on either side of this the trochlear nerve emerges.
Blood is supplied by branches from the superior cerebellar artery.
The medulla oblongata or simply medulla is a long stem-like structure which makes up the lower part of the brainstem. It is anterior and partially inferior to the cerebellum. It is a cone-shaped neuronal mass responsible for autonomic (involuntary) functions, ranging from vomiting to sneezing. The medulla contains the cardiovascular center, the respiratory center, vomiting and vasomotor centers, responsible for the autonomic functions of breathing, heart rate and blood pressure as well as the sleep–wake cycle. "Medulla" is from Latin, ‘pith or marrow’. And "oblongata" is from Latin, ‘lengthened or longish or elongated'.
Articles related to anatomy include:
The brainstem is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is continuous with the thalamus of the diencephalon through the tentorial notch, and sometimes the diencephalon is included in the brainstem.
The midbrain or mesencephalon is the rostral-most portion of the brainstem connecting the diencephalon and cerebrum with the pons. It consists of the cerebral peduncles, tegmentum, and tectum.
The cerebral aqueduct is a small, narrow tube connecting the third and fourth ventricles of the brain. The cerebral aqueduct is a midline structure that passes through the midbrain. It extends rostrocaudally through the entirety of the more posterior part of the midbrain. It is surrounded by the periaqueductal gray, a layer of gray matter.
Velum may refer to:
The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. These cavities, known collectively as the ventricular system, consist of the left and right lateral ventricles, the third ventricle, and the fourth ventricle. The fourth ventricle extends from the cerebral aqueduct to the obex, and is filled with cerebrospinal fluid (CSF).
The olivary bodies or simply olives are a pair of prominent oval structures on either side of the medullary pyramids in the medulla, the lower portion of the brainstem. They contain the olivary nuclei.
The lentiform nucleus are the putamen (laterally) and the globus pallidus (medially), collectively. Due to their proximity, these two structures were formerly considered one, however, the two are separated by a thin layer of white matter - the external medullary lamina - and are functionally and connectionally distinct.
The inferior cerebellar peduncle is formed by fibers of the restiform body that join with fibers from the much smaller juxtarestiform body. The inferior cerebellar peduncle is the smallest of the three cerebellar peduncles.
The subarachnoid cisterns are spaces formed by openings in the subarachnoid space, an anatomic space in the meninges of the brain. The space is situated between the two meninges, the arachnoid mater and the pia mater. These cisterns are filled with cerebrospinal fluid (CSF).
The cisterna magna is the largest of the subarachnoid cisterns. It occupies the space created by the angle between the caudal/inferior surface of the cerebellum, and the dorsal/posterior surface of the medulla oblongata. The fourth ventricle communicates with the cistern via the unpaired midline median aperture. It is continuous inferiorly with the subarachnoid space of the spinal canal.
The posterior inferior cerebellar artery (PICA) is the largest branch of the vertebral artery. It is one of the three main arteries that supply blood to the cerebellum, a part of the brain. Blockage of the posterior inferior cerebellar artery can result in a type of stroke called lateral medullary syndrome.
The superior cerebellar artery (SCA) is an artery of the head. It arises near the end of the basilar artery. It is a branch of the basilar artery. It supplies parts of the cerebellum, the midbrain, and other nearby structures. It is the cause of trigeminal neuralgia in some patients.
The cerebellar peduncles are three paired bundles of fibres that connect the cerebellum to the brain stem.
The rhomboid fossa is a rhombus-shaped depression that is the anterior part of the fourth ventricle. Its anterior wall, formed by the back of the pons and the medulla oblongata, constitutes the floor of the fourth ventricle.
In the human brain, the superior cerebellar peduncle is one of the three paired cerebellar peduncles of bundled fibers that connect the cerebellum to the brainstem. The superior cerebellar peduncle connects to the midbrain. It consists mainly of efferent fibers, the cerebellothalamic tract that runs from a cerebellar hemisphere to the contralateral thalamus, and the cerebellorubral tract that runs from a cerebellar hemisphere to the red nucleus. It also contains afferent tracts, most prominent of which is the ventral spinocerebellar tract. Other afferent tracts are the ventral trigeminal tract, tectocerebellar fibers, and noradrenergic fibers from the locus coeruleus. The superior peduncle emerges from the upper and medial parts of the white matter of each cerebellar hemisphere and is placed under cover of the upper part of the cerebellum.
The middle cerebellar peduncle is one of three paired cerebellar peduncles connecting the brainstem to the cerebellum. The connection is from the pons. It connects the pons to the cerebellum, with fibres originating from the pontine nuclei, and travelling to the opposite cerebellar hemisphere. It is supplied by the anterior inferior cerebellar artery (AICA) and branches from the basilar artery. It conveys information from the cerebrum and the pons to the cerebellum.
The roof of fourth ventricle is the dorsal surface of the fourth ventricle.
This article incorporates text in the public domain from page 793 of the 20th edition of Gray's Anatomy (1918)