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Medullary Striae Of Fourth Ventricle
Medullary striae of fourth ventricle are a landmark of the rhomboid fossa - the floor of the fourth ventricle. They are part of the auditory system. The medullary striae are formed by crossed-over anterior internal arcuate fibers - efferents of the arcuate nucleus of medulla oblongata - as they pass laterally beneath the ependyma of the fourth ventricle to reach the contralateral cerebellum. The striae pass over the dorsal aspect of the medial vestibular nucleus. The medullary striae delineate the boundary between the pons and medulla oblongata 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 (involun ... dorsally/posteriorly. Additional images File:Slide2PITER.JPG, Fourth ventricle. Posterior view. Deep dissection. References External links Diagram at UMich Vestibulocochlear n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhomboid Fossa
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. It is covered by a thin layer of grey matter continuous with that of the spinal cord; superficial to this is a thin lamina of neuroglia which constitutes the ependyma of the Ventricular system, ventricle and supports a layer of ciliated epithelium. Parts The fossa consists of three parts, superior, intermediate, and inferior: ;The superior part :The superior part is triangular in shape and limited laterally by the superior cerebellar peduncle; its apex, directed upward, is continuous with the cerebral aqueduct; its base is represented by an imaginary line at the level of the upper ends of the superior foveae. ;The intermediate part :The intermediate part extends from this level to that of the horizontal portions of the Taenia of fourth ventricle, taeniae of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fourth Ventricle
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 (''aqueduct of Sylvius'') to the obex, and is filled with cerebrospinal fluid (CSF). The fourth ventricle has a characteristic diamond shape in cross-sections of the human brain. It is located within the pons or in the upper part of the medulla oblongata. CSF entering the fourth ventricle through the cerebral aqueduct can exit to the subarachnoid space of the spinal cord through two lateral apertures and a single, midline median aperture. Boundaries The fourth ventricle has a roof at its ''upper'' (posterior) surface and a floor at its ''lower'' (anterior) surface, and side walls formed by the cerebellar peduncles (nerve bundles joining the structure on the post ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Internal Arcuate Fibers
Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and axes. The meaning of terms that are used can change depending on whether a vertebrate is a biped or a quadruped, due to the difference in the neuraxis, or if an invertebrate is a non-bilaterian. A non-bilaterian has no anterior or posterior surface for example but can still have a descriptor used such as proximal or distal in relation to a body part that is nearest to, or furthest from its middle. International organisations have determined vocabularies that are often used as standards for subdisciplines of anatomy. For example, ''Terminologia Anat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcuate Nucleus (medulla)
In the medulla oblongata, the arcuate nucleus is a group of neurons located on the anterior surface of the medullary pyramids. These nuclei are the extension of the pontine nuclei. They receive afferents from the corticospinal tract. They in turn project efferents into the cerebellum through the inferior cerebellar peduncle as: * the anterior internal arcuate fibers which pass along the midline before decussating near the rhomboid fossa (floor of fourth ventricle) then passing laterally as the medullary striae; * the anterior external arcuate fibers. Function Arcuate nuclei are capable of chemosensitivity and have a proven role in the respiratory center controlling the breathing rate The respiratory rate is the rate at which breathing occurs; it is set and controlled by the respiratory center of the brain. A person's respiratory rate is usually measured in breaths per minute. Measurement The respiratory rate in humans is me .... Additional images File:Gray699.png, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elsevier
Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell (journal), Cell'', the ScienceDirect collection of electronic journals, ''Trends (journals), Trends'', the ''Current Opinion (Elsevier), Current Opinion'' series, the online citation database Scopus, the SciVal tool for measuring research performance, the ClinicalKey search engine for clinicians, and the ClinicalPath evidence-based cancer care service. Elsevier's products and services include digital tools for Data management platform, data management, instruction, research analytics, and assessment. Elsevier is part of the RELX Group, known until 2015 as Reed Elsevier, a publicly traded company. According to RELX reports, in 2022 Elsevier published more than 600,000 articles annually in over 2,800 journals. As of 2018, its archives contained over 17 million documents and 40,000 Ebook, e-books, with over one b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medial Vestibular Nucleus
The medial vestibular nucleus (Schwalbe nucleus) is one of the vestibular nuclei. It is located in the medulla oblongata. Lateral vestibulo-spinal tract (lateral vestibular nucleus “Deiters”)- via ventrolateral medulla and spinal cord to ventral funiculus (lumbo-sacral segments). ..Ipsilaterally for posture Medial vestibulo-spinal tract (medial, lateral, inferior, vestibular nuclei), bilateral projection via descending medial longitudinal fasciculus to cervical segments. DESCENDING MLF..Bilaterally for head/neck/eye movements It is one of the nuclei that corresponds to CN VIII, corresponding to the vestibular nerve, which joins with the cochlear nerve. It receives its blood supply from the Posterior Inferior Cerebellar Artery, which is compromised in the lateral medullary syndrome. See also * Vestibular nerve * Vestibular system The vestibular system, in vertebrates, is a sensory system that creates the sense of balance and spatial orientation for the purpose of coordin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pons
The pons (from Latin , "bridge") is part of the brainstem that in humans and other mammals, lies inferior to the midbrain, superior to the medulla oblongata and anterior to the cerebellum. The pons is also called the pons Varolii ("bridge of Varolius"), after the Italian anatomist and surgeon Costanzo Varolio (1543–75). This region of the brainstem includes neural pathways and tracts that conduct signals from the brain down to the cerebellum and medulla, and tracts that carry the sensory signals up into the thalamus. Structure The pons in humans measures about in length. It is the part of the brainstem situated between the midbrain and the medulla oblongata. The horizontal ''medullopontine sulcus'' demarcates the boundary between the pons and medulla oblongata on the ventral aspect of the brainstem, and the roots of cranial nerves VI/VII/VIII emerge from the brainstem along this groove. The junction of pons, medulla oblongata, and cerebellum forms the cerebellopontine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medulla Oblongata
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'. During embryonic development, the medulla oblongata develops from the myelencephalon. The myelencephalon is a secondary brain vesicle which forms during the maturation of the rhombencephalon, also referred to as the hindbrain. The bulb is an archaic term for the medulla oblongata. In modern clinical usage, the word bulbar (as in bulbar palsy) is r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestibulocochlear Nerve
The vestibulocochlear nerve or auditory vestibular nerve, also known as the eighth cranial nerve, cranial nerve VIII, or simply CN VIII, is a cranial nerve that transmits sound and equilibrium (balance) information from the inner ear to the brain. Through olivocochlear fibers, it also transmits motor and modulatory information from the superior olivary complex in the brainstem to the cochlea. Structure The vestibulocochlear nerve consists mostly of bipolar neurons and splits into two large divisions: the cochlear nerve and the vestibular nerve. Cranial nerve 8, the vestibulocochlear nerve, goes to the middle portion of the brainstem called the pons (which then is largely composed of fibers going to the cerebellum). The 8th cranial nerve runs between the base of the pons and medulla oblongata (the lower portion of the brainstem). This junction between the pons, medulla, and cerebellum that contains the 8th nerve is called the cerebellopontine angle. The vestibulocochlea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
