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Nucleus Raphe Obscurus
The nucleus raphe obscurus is one of the medullary raphe nuclei. It is located caudal to the nucleus raphe magnus. The nucleus raphe obscurus projects to the cerebellar lobes VI and VII and to crus II along with the nucleus raphe pontis. The nucleus raphes obscurus has also been implicated in the modulation of the hypoglossal nerve. It has been observed that the ablation of this nucleus causes a change in the firing pattern of this cranial nerve. In addition, the nucleus raphe obscurus mediates expiration via the effect of serotonin and depresses periodic synaptic potentials. It has also been shown that this nucleus stimulates gastrointestinal motor function; microinjections of 5-HT into the nucleus raphe obscurus increase gastric movement. See also * Raphe nuclei The raphe nuclei (, "seam") are a moderate-size cluster of nuclei found in the brain stem. They have 5-HT1 receptors which are coupled with Gi/Go-protein-inhibiting adenyl cyclase. They function as autoreceptors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleus Raphe Magnus
The nucleus raphe magnus (NRM) is one of the seven raphe nuclei. It is situated in the pons in the brainstem, just rostral to the nucleus raphe obscurus. The NRM receives afferent stimuli from the enkephalinergic neurons of the periaqueductal gray; the serotonergic neurons of the NRM then bilaterally project efferents to the enkephalinergic and dynorphin-containing interneurons of the substantia gelatinosa of the posterior grey column of the spinal cord. This neural path thus mediates pain perception through pre-synaptic inhibition of first-order afferent (sensory) neurons. Anatomy Afferents It receives afferents from the spinal cord and cerebellum. It receives descending afferents from the periaqueductal grey matter (PAG), the paraventricular hypothalamic nucleus, central nucleus of the amygdala, lateral hypothalamic area, parvocellular reticular nucleus and the prelimbic, infralimbic, medial and lateral precentral cortices. It is one of the afferent targets of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellum
The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or even larger. In humans, the cerebellum plays an important role in motor control and cognition, cognitive functions such as attention and language as well as emotion, emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to motor coordination, coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity. Cerebellar damage produces disorders in fine motor skill, fine movement, sense of balance, equilibrium, list of human positions, posture, and motor learning in humans. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleus Raphe Pontis
The pontine raphe nucleus is one of the raphe nuclei. It is located in the pontine tegmentum The pontine tegmentum, or dorsal pons, is the dorsal part of the pons located within the brainstem. The ventral part or ventral pons is known as the basilar part of the pons, or basilar pons. Along with the dorsal surface of the medulla oblonga .... References Pons {{Neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoglossal Nerve
The hypoglossal nerve, also known as the twelfth cranial nerve, cranial nerve XII, or simply CN XII, is a cranial nerve that innervates all the extrinsic and intrinsic muscles of the tongue except for the palatoglossus, which is innervated by the vagus nerve. CN XII is a nerve with a sole motor function. The nerve arises from the hypoglossal nucleus in the medulla as a number of small rootlets, pass through the hypoglossal canal and down through the neck, and eventually passes up again over the tongue muscles it supplies into the tongue. The nerve is involved in controlling tongue movements required for speech and swallowing, including sticking out the tongue and moving it from side to side. Damage to the nerve or the neural pathways which control it can affect the ability of the tongue to move and its appearance, with the most common sources of damage being injury from trauma or surgery, and motor neuron disease. The first recorded description of the nerve was by Her ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ablation
Ablation ( – removal) is the removal or destruction of something from an object by vaporization, chipping, erosion, erosive processes, or by other means. Examples of ablative materials are described below, including spacecraft material for ascent and atmospheric reentry, ice and snow in glaciology, biological tissues in medicine and passive fire protection materials. Artificial intelligence In artificial intelligence (AI), especially machine learning, Ablation (artificial intelligence), ablation is the removal of a component of an AI system. The term is by analogy with biology: removal of components of an organism. Biology Biological ablation is the removal of a biological structure or functionality. Genetic ablation is another term for gene silencing, in which gene expression is abolished through the alteration or deletion of genetic sequence information. In cell ablation, individual cells in a population or culture are destroyed or removed. Both can be used as experimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cranial Nerves
Cranial nerves are the nerves that emerge directly from the brain (including the brainstem), of which there are conventionally considered twelve pairs. Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck, including the special senses of Visual perception, vision, taste, Olfaction, smell, and hearing. The cranial nerves emerge from the central nervous system above the level of the Atlas (anatomy), first vertebra of the vertebral column. Each cranial nerve is paired and is present on both sides. There are conventionally twelve pairs of cranial nerves, which are described with Roman numerals I–XII. Some considered there to be thirteen pairs of cranial nerves, including the non-paired cranial nerve zero. The numbering of the cranial nerves is based on the order in which they emerge from the brain and brainstem, from front to back. The terminal nerves (0), olfactory nerves (I) and optic nerves (II) emerge f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exhalation
Exhalation (or expiration) is the flow of the breathing, breath out of an organism. In animals, it is the movement of air from the lungs out of the airways, to the external environment during breathing. This happens due to elastic properties of the lungs, as well as the internal intercostal muscles which lower the rib cage and decrease thoracic volume. As the thoracic diaphragm relaxes during exhalation it causes the tissue it has depressed to rise superiorly and put pressure on the lungs to expel the air. During Hyperpnea, forced exhalation, as when blowing out a candle, expiratory muscles including the abdominal muscles and internal intercostal muscles generate abdominal and thoracic pressure, which forces air out of the lungs. Exhaled air is 4% carbon dioxide, a waste product of cellular respiration during the production of energy, which is stored as Adenosine triphosphate, ATP. Exhalation has a complementary relationship to inhalation which together make up the respirator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotonin
Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, memory, and physiological processes such as vomiting and vasoconstriction. In the CNS, serotonin regulates mood, appetite, and sleep. Most of the body's serotonin—about 90%—is synthesized in the gastrointestinal tract by enterochromaffin cells, where it regulates intestinal movements. It is also produced in smaller amounts in the brainstem's raphe nuclei, the skin's Merkel cells, pulmonary neuroendocrine cells, and taste receptor cells of the tongue. Once secreted, serotonin is taken up by platelets in the blood, which release it during clotting to promote vasoconstriction and platelet aggregation. Around 8% of the body's serotonin is stored in platelets, and 1–2% is found in the CNS. Serotonin acts as both a vasoconstrictor and vas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raphe Nuclei
The raphe nuclei (, "seam") are a moderate-size cluster of nuclei found in the brain stem. They have 5-HT1 receptors which are coupled with Gi/Go-protein-inhibiting adenyl cyclase. They function as autoreceptors in the brain and decrease the release of serotonin. The anxiolytic drug Buspirone acts as partial agonist against these receptors. Selective serotonin reuptake inhibitor (SSRI) antidepressants are believed to act in these nuclei, as well as at their targets. Anatomy The raphe nuclei are traditionally considered to be the medial portion of the reticular formation, and appear as a ridge of cells in the center and most medial portion of the brain stem. In order from caudal to rostral, the raphe nuclei are known as the '' nucleus raphe obscurus'', the '' nucleus raphe pallidus'', the '' nucleus raphe magnus'', the '' nucleus raphe pontis'', the '' median raphe nucleus'', ''dorsal raphe nucleus'', ''caudal linear nucleus''. In the first systematic examination of the raph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
