FACTOID # 8: Bookworms: Vermont has the highest number of high school teachers per capita and third highest number of librarians per capita.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Nucleus raphe magnus

The nucleus raphe magnus, located directly rostral to the raphe obscurus, is afferently stimulated from axons in the spinal cord and cerebellum. This makes the magnus a likely candidate for part of the motor system; however, it seems to participate in the endogenous analgesia system. The magnus receives descending afferents from the periaqueductal gray, the paraventricular hypothalamic nucleus, central nucleus of the amygdala, lateral hypothalamic area, parvocellular reticular nucleus and the prelimbic, infralimbic, medial and lateral precentral cortices (Hermann, Dirk M. et al. Afferent projections to the rat nuclei raphe magnus, raphe pallidus and reticularis gigantocellularis pars demonstrated by iontophoretic application of choleratoxin (subunit b). Journal of Chemical Neuroanatomy Volume 13, Issue 1 , June 1997, Pages 1-21). All of these brain areas influence the main function of the raphe magnus. The main function of the magnus is mostly pain mediation; in fact it sends projections to the dorsal horn of the spinal cord to directly inhibit pain. The periaquiductal gray, the epicenter of analgesia, sends efferent connections to the nucleus raphe magnus in when it is stimulated by opiates (endogenous or otherwise). Electrical stimulation of the PAG produces analgesia, as well as administration of morphine to the PAG or n.r. magnus. The antinociceptic affects of electrical stimulation of the PAG can be blocked by administering naloxone, an opiate antagonist, to the n.r. magnus. All of this seems to indicate that the magnus is part of the endogenous opiate system, and acts to inhibit pain in the spinal cord. Cross-section through cervical spinal cord. ... Figure 1a: A human brain, with the cerebellum in purple. ... Structure of a skeletal muscle Muscle is one of the four tissue types. ... PeriAqueductal Gray (PAG) is the tegmental gray matter that is located around the cerebral aqueduct; it plays a role in the suppression of pain and in defensive behavior. ... Location of the amygdala in the human brain The amygdala (Latin, corpus amygdaloideum) is an almond-shaped set of neurons located deep in the brains medial temporal lobe. ... For other uses of painkiller, see painkiller (disambiguation) An analgesic (colloquially known as painkiller) is any member of the diverse group of drugs used to relieve pain. ... For other uses of painkiller, see painkiller (disambiguation) An analgesic (colloquially known as painkiller) is any member of the diverse group of drugs used to relieve pain. ... Naloxone is a drug used to counter the effects of overdosing on opioids such as heroin and morphine. ... The antagonist is the character (or group of characters, or, sometimes an institution) of a story who represents the opposition against which the heroes and/or protagonists must contend. ...


See also

The raphe nuclei (Latin for the bit in a fold or seam) is a moderately sized cluster of nuclei found in the brain stem, and releases serotonin to the rest of the brain. ...

External links

Rhombencephalon (hindbrain)

MYELENCEPHALON/MEDULLA: arcuate nucleus of medulla, solitary nucleus, hypoglossal nucleus, nucleus ambiguus, olivary body, cuneate nucleus, accessory cuneate nucleus, gracile nucleus, inferior salivatory nucleus, nucleus raphe obscurus, nucleus raphe magnus, nucleus raphe pallidus The University of Washington, founded in 1861, is a major public research university in Seattle, Washington. ... Wikipedia does not have an article with this exact name. ... The myelencephalon is a developmental categorization of a portion of the central nervous system. ... Position of medulla oblangata in the human brain The medulla oblongata is the lower portion of the brainstem. ... Grays Fig. ... The solitary nucleus and tract are structures in the brainstem that carry and receive visceral sensation and taste from the facial (VII), glossopharyngeal (IX), vagus (X) cranial nerves, as well as the cranial part of the accessory nerve (XI). ... The hypoglossal nerve is the twelfth cranial nerve. ... The nucleus ambiguus is a cranial nerve nucleus, located in the medulla oblongata, and handles the branchial motor functions of the ninth (glossopharyngeal) and tenth (vagus) cranial nerves. ... In anatomy, the olivary bodies or simply olives (Latin oliva) are a pair of prominent oval structures in the medulla oblongata, the lower portion of the brainstem. ... Cuneate nucleus is a wedge-shaped nucleus in the medulla. ... The accessory cuneate nucleus is located lateral to the cuneate nucleus in the medulla oblongata at the level of the sensory decussation (the crossing fibers of the posterior column/medial lemniscus tract). ... The swelling on the fasciculus gracilis is named the clava, and is produced by a subjacent nucleus of gray matter, the nucleus gracilis. ... The inferior salivatory nucleus is one of the components of the glossopharyngeal nerve, which stimulates secretion from the parotid gland. ...


METENCEPHALON/CEREBELLUM: cerebellar vermis, flocculus, arbor vitae The metencephalon is a developmental categorization of portions of the central nervous system. ... Figure 1a: A human brain, with the cerebellum in purple. ... Part of the structure of animal brains, the cerebellar vermis is a narrow, wormlike structure between the hemispheres of the cerebellum. ... The flocculus is a small lobe of the cerebellum at the posterior border of the middle cerebellar peduncle anterior to the biventer lobule; it is associated with the nodulus of the vermis; together, these two structures compose the vestibular part of the cerebellum. ... The arbor vitae (Tree of Life) refers to the cerebellar white matter, so called for its branched, tree-like appearance. ...


METENCEPHALON/PONS: pontine tegmentum, trapezoid body, pontine nuclei (superior olivary nucleus, trigeminal nerve nuclei, abducens nucleus, facial nucleus, cochlear nuclei, vestibular nuclei), locus ceruleus, paramedian pontine reticular formation, nucleus centralis superior The metencephalon is a developmental categorization of portions of the central nervous system. ... Position of the pons in the human brain The pons (sometimes pons Varolii after Costanzo Varolio) is a knob on the brain stem. ... The pontine tegmentum is a part of the pons of the brain involved in the initiation of REM sleep. ... The trapezoid body is part of the acoustic pathway. ... The pontine nuclei are a part of the pons which store the memory of intention during motor activity. ... // Anatomy The superior olivary nucleus (or superior olive) is a small mass of gray substance situated on the dorsal surface of the lateral part of the trapezoid body. ... The abducens nucleus is the originating nucleus from which the abducens nerve emerges. ... The cranial nerve motor nucleus of the facial nerve is located in the lower pons. ... The cochlear nuclei consist of: (a) the lateral cochlear nucleus, corresponding to the tuberculum acusticum on the dorso-lateral surface of the inferior peduncle; and (b) the ventral or accessory cochlear nucleus, placed between the two divisions of the nerve, on the ventral aspect of the inferior peduncle. ... The Locus ceruleus, also spelled locus coeruleus, (Latin for the blue bit) is a nucleus in the brain stem (under the cerebellum in the caudal midbrain/rostral pons) apparently responsible for the physiological reactions involved in stress and panic. ... The paramedian pontine reticular formation, or PPRF, is a brain region, without clearly defined borders, in the center of the pons. ... The nucleus centralis superior is composed of polygonal, fusiform and pyriform neurons and exists rostral to the nucleus raphe pontis. ...


FOURTH VENTRICLE: obex, median aperture The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. ... IrOBEX (or just OBEX) is a communications protocol that facilitates the exchange of binary objects between devices. ... The Median Aperture of the brain (apertura medialis ventriculi quarte) or Foramen of Magendie is an opening in the hollow nerve tube, connecting the 4th ventricle of the brain with the subarachnoid space The median aperture along with the paired lateral apertures (foramina of Luschka) are the primary routes for...


 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m