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Paramedian Reticular Nucleus
The paramedian reticular nucleus (in Terminologia Anatomica, or paramedian medullary reticular group in NeuroNames) sends its connections to the spinal cord in a mostly ipsilateral manner, although there is some decussation. It projects to the vermis in the anterior lobe, the pyramis and the uvula. The paramedian nucleus also projects to the contralateral PRN, the gigantocellular nucleus, and the nucleus ambiguous. The paramedian reticular formation is adjacent to the abducens (VI)nucleus in the pons and adjacent to the oculomotor nucleus(III) in the midbrain. The paramedian nucleus receives afferents mostly from the fastigial nucleus in the cerebellum and the cerebral cortex; however, the projections from the spinal cord are very sparse. The descending afferent connections come mostly from the frontal and parietal lobes; however the pontine reticular formation also sends projections to the paramedian reticular nucleus. There are also very sparse innervations from the superio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terminologia Anatomica
''Terminologia Anatomica'' (commonly abbreviated TA) is the international standard for human anatomy, human anatomical terminology. It is developed by the Federative International Programme on Anatomical Terminology (FIPAT) a program of the International Federation of Associations of Anatomists (IFAA). History The sixth edition of the previous standard, ''Nomina Anatomica'', was released in 1989. The first edition of ''Terminologia Anatomica'', superseding Nomina Anatomica, was developed by the Federative Committee on Anatomical Terminology (FCAT) and the International Federation of Associations of Anatomists (IFAA) and released in 1998. In April 2011, this edition was published online by the Federative International Programme on Anatomical Terminologies (FIPAT), the successor of FCAT. The first edition contained 7635 Latin items. The second edition was released online by FIPAT in 2019 and approved and adopted by the IFAA General Assembly in 2020. The latest errata is dated Au ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NeuroNames
''NeuroNames'' is an integrated nomenclature for structures in the brain and spinal cord of the four species most studied by neuroscientists: human, macaque, rat and mouse. It offers a standard, controlled vocabulary of common names for structures, which is suitable for unambiguous neuroanatomical indexing of information in digital databases. Terms in the standard vocabulary have been selected for ease of pronunciation, mnemonic value, and frequency of use in recent neuroscientific publications. Structures and their relations to each other are defined in terms of the standard vocabulary. Currently NeuroNames contains standard names, synonyms and definitions of some 2,500 neuroanatomical entities. The nomenclature is maintained by the University of Washington and is the core component of a tool called "BrainInfo". BrainInfo helps one identify structures in the brain. One can either search by a structure name or locate the structure in a brain atlas and get information such as it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermis
The cerebellar vermis (from Latin ''vermis,'' "worm") is located in the medial, cortico-nuclear zone of the cerebellum, which is in the posterior fossa of the cranium. The primary fissure in the vermis curves ventrolaterally to the superior surface of the cerebellum, dividing it into anterior and posterior lobes. Functionally, the vermis is associated with bodily posture and locomotion. The vermis is included within the spinocerebellum and receives somatic sensory input from the head and proximal body parts via ascending spinal pathways. The cerebellum develops in a rostro-caudal manner, with rostral regions in the midline giving rise to the vermis, and caudal regions developing into the cerebellar hemispheres. By 4 months of prenatal development, the vermis becomes fully foliated, while development of the hemispheres lags by 30–60 days. Postnatally, proliferation and organization of the cellular components of the cerebellum continues, with completion of the foliati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uvula
The uvula (: uvulas or uvulae), also known as the palatine uvula or staphyle, is a conic projection from the back edge of the middle of the soft palate, composed of connective tissue containing a number of racemose glands, and some muscular fibers. It also contains many serous glands, which produce thin saliva. It is only found in humans. Structure Muscle The muscular part of the uvula () shortens and broadens the uvula. This changes the contour of the posterior part of the soft palate. This change in contour allows the soft palate to adapt closely to the posterior pharyngeal wall to help close the nasopharynx during swallowing. Its muscles are controlled by the pharyngeal branch of the vagus nerve. Variation A bifid or bifurcated uvula is a split or cleft uvula. Newborns with cleft palate often also have a split uvula. The bifid uvula results from incomplete fusion of the palatine shelves but it is considered only a slight form of clefting. Bifid uvulas have les ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gigantocellular Nucleus
The gigantocellular reticular nucleus (also magnocellular reticular nucleus) is the (efferent/motor) medial zone of the reticular formation of the caudal pons and rostral medulla oblongata. It consists of a substantial number of giant neurons, but also contains small and medium sized neurons. It gives rise to the lateral (medullary) reticulospinal tract which influences muscle tone of limb and trunk muscles, is involved in coordination of head-eye movements, promotes parasympathetic reduction of heart rate to decrease blood pressure, induces inspiration, and participates in the descending pain-inhibiting pathway. Anatomy Afferents It receives connections from the periaqueductal gray, the paraventricular hypothalamic nucleus, central nucleus of the amygdala, lateral hypothalamic area, and parvocellular reticular nucleus. It receives afferent corticoreticular fibers from the premotor cortex and supplementary motor area which modulate the activity of reticulospinal and reticul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleus Ambiguous
The nucleus ambiguus ("ambiguous nucleus" in English) is a group of large motor neurons, situated deep in the medullary part of the reticular formation named by Jacob Clarke. The nucleus ambiguus contains the cell bodies of neurons that innervate the muscles of the soft palate, pharynx, and larynx which are associated with speech and swallowing. As well as motor neurons, the nucleus ambiguus contains preganglionic parasympathetic neurons which innervate postganglionic parasympathetic neurons in the heart.Machado, BH and Brody, MJ"Role MJ of the nucleus ambiguus in the regulation of heart rate and arterial pressure."/ref> It is a region of histologically disparate cells located just dorsal ( posterior) to the inferior olivary nucleus in the lateral portion of the upper (rostral) medulla. It receives upper motor neuron innervation directly via the corticobulbar tract. This nucleus gives rise to the branchial efferent motor fibers of the vagus nerve (CN X) terminating in the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fastigial Nucleus
The fastigial nucleus (roof nucleus-1) is located in each cerebellar hemisphere. It is one of the four paired deep cerebellar nuclei of the cerebellum. It is made up of two sections: the rostral fastigial nucleus and the caudal fastigial nucleus. Anatomy The fastigial nuclei is situated atop the roof of the fourth ventricle (thence its name: "''fastigus''" is Latin for "summit"). The fastigial nucleus is a mass of gray matter nearest to the middle line at the anterior end of the superior vermis, immediately over the roof of the fourth ventricle (the peak of which is called the ''fastigium''), from which it is separated by a thin layer of white matter. It is smaller than the dentate nucleus, but somewhat larger than the emboliform nucleus and globose nucleus. Afferents The fastigial nucleus receives afferents from the vestibulocerebellar tract (containing first-order axons from the vestibular nerve as well as second-order axons from the vestibular nuclei), and fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superior Colliculus
In neuroanatomy, the superior colliculus () is a structure lying on the tectum, roof of the mammalian midbrain. In non-mammalian vertebrates, the Homology (biology), homologous structure is known as the optic tectum or optic lobe. The adjective form ''tectum, tectal'' is commonly used for both structures. In mammals, the superior colliculus forms a major component of the midbrain. It is a paired structure and together with the paired inferior colliculi forms the corpora quadrigemina. The superior colliculus is a layered structure, with a pattern that is similar in all mammals. The layers can be grouped into the superficial layers (retinal nerve fiber layer, stratum opticum and above) and the deeper remaining layers. Neurons in the superficial layers receive direct input from the retina and respond almost exclusively to visual stimuli. Many neurons in the deeper layers also respond to other modalities, and some respond to stimuli in multiple modalities. The deeper layers also conta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eye Movement (sensory)
Eye movement includes the voluntary or involuntary movement of the eyes. Eye movements are used by a number of organisms (e.g. primates, rodents, flies, birds, fish, cats, crabs, octopus) to fixate, inspect and track visual objects of interests. A special type of eye movement, rapid eye movement, occurs during REM sleep. The eyes are the visual organs of the human body, and move using a system of six muscles. The retina, a specialised type of tissue containing photoreceptors, senses light. These specialised cells convert light into electrochemical signals. These signals travel along the optic nerve fibers to the brain, where they are interpreted as vision in the visual cortex. Primates and many other vertebrates use three types of voluntary eye movement to track objects of interest: smooth pursuit, vergence shifts and saccades. These types of movements appear to be initiated by a small cortical region in the brain's frontal lobe. This is corroborated by removal of the fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ipsilateral
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, '' Terminolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paramedian Pontine Reticular Formation
The paramedian pontine reticular formation (PPRF) is a subset of neurons of the oral and caudal pontine reticular nuclei. With the abducens nucleus it makes up the horizontal gaze centre. It is situated in the pons adjacent to the abducens nucleus. It projects to the ipsilateral abducens (cranial nerve VI) nucleus, and contralateral oculomotor (cranial nerve III) nucleus to mediate conjugate horizontal gaze and saccades. Anatomy The PPRF is situated in the pons just ventralmedial to the abducens nucleus. It is located anterior and lateral to the medial longitudinal fasciculus. It is continuous caudally with the nucleus prepositus hypoglossi. The PPRF (and adjacent regions of the pons) are traversed by fibers projecting to the abducens nucleus that mediate smooth pursuit, vestibular reflexes, and gaze holding. Afferents The PPRF receives afferents from: * contralateral frontal eye field of the middle frontal gyrus of the frontal lobe (via frontopontine fibers The f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
