Cranial nerve nucleus 3419845 208448421 2008-04-27T02:49:02Z Arcadian 104523 /* Arrangement of the nuclei */ wik {{Infobox Brain| Name = Cranial nerve nucleus | Latin = | GraySubject = 195 | GrayPage = 881 | Image = Gray696.png | Caption = The cranial nerve nuclei schematically represented; dorsal view. Motor nuclei in red; sensory in blue. (The olfactory and optic centers are not represented.) | Image2 = | Caption2 = | IsPartOf = | Components = | Artery = | Vein = | BrainInfoType = | BrainInfoNumber = | MeshName = | MeshNumber = | }} A '''cranial nerve nucleus''' is a collection of [[neuron]]s ([[gray matter]]) in the [[brain stem]] that is associated with one or more [[cranial nerves]]. [[Axon]]s carrying information to and from the cranial nerves form a [[synapse]] first at these [[nucleus (neuroanatomy)|nuclei]]. Lesions occurring at these nuclei can lead to effects resembling those seen by the severing of nerve(s) they are associated with. All the nuclei excepting that of the IV nerve supply nerves of the same side of the body. ==Arrangement of the nuclei== Just as grey matter in the ventral (closer to front of a human) [[spinal cord]] tends to be efferent (motor) fibers, and the dorsal horn tends to contain sensory [[neuron]]s, nuclei in the brainstem are arranged in an analogous way. * Close to the midline are the '''[[motor efferent nuclei]]''', such as the [[oculomotor nucleus]], which control skeletal muscle. Just lateral to this are the '''autonomic (or visceral) efferent nuclei.''' * There is a separation, called the [[sulcus limitans]], and lateral to this are the '''sensory nuclei'''. Near the sulcus limitans are the '''[[visceral afferent]] nuclei''', namely the [[solitary tract nucleus]]. * More lateral, but also less posterior, are the '''[[general somatic afferent]] nuclei'''. This is the [[trigeminal nucleus]]. Back at the dorsal surface of the brainstem, and more lateral are the '''[[special somatic afferent]]s''', this handles sensation such as balance. * Another area, not on the dorsum of the brainstem, is where the '''[[branchial efferent]] nuclei''' reside. These formed from the [[branchial arch]]es, in the embryo. This area is a bit below the '''autonomic motor nuclei''', and includes the [[nucleus ambiguus]], [[facial nerve]] nucleus, as well as the motor part of the [[trigeminal nerve]] nucleus. ==Examples of nuclei== There are several cranial nerve nuclei (roman numeral refers to the cranial nerve number): ===[[hindbrain]] (''rhombencephalon'')=== ====[[medulla oblongata]]==== * [[Hypoglossal nucleus]] (XII) - motor * [[Dorsal motor nucleus of vagus nerve]] (X) - visceromotor * [[Nucleus ambiguus]] (IX, X, XI) - motor * [[Solitary nucleus]] (VII, IX, X) - sensory * [[Spinal trigeminal nucleus]] (V) - sensory * [[Inferior olivary nucleus]] afferent fibres to cerebellum ====[[pons]]==== * [[Cochlear nuclei]] (VIII) - sensory ** [[Dorsal cochlear nucleus]] ** [[Ventral cochlear nucleus]] * [[Vestibular nuclei]] (VIII) - sensory * [[Salivary nuclei]] - visceromotor ** [[Inferior salivary nucleus]] (IX) ** [[Superior salivary nucleus]] (VII) * [[Facial nucleus]] (VII) - motor * [[Abducens nucleus]] (VI) - motor * [[Trigeminal motor nucleus]] (V) - motor * [[Spinal trigeminal nucleus]] (V) - sensory ===[[midbrain]] (''mesencephalon'')=== * [[Mesencephalic trigeminal nucleus]] (V) - sensory * [[Red nucleus]] - motor, extrapyramidal * [[Trochlear nucleus]] (IV) - motor * [[Oculomotor nucleus]] (III) - motor * [[Edinger-Westphal nucleus]] (III) - visceromotor ==References== * [[Lennart Heimer]], ''The Human Brain'', ISBN 0-387-94227-0 ==Additional images== <gallery> Image:Gray697.png|Nuclei of origin of cranial motor nerves schematically represented; lateral view. Image:Gray698.png|Primary terminal nuclei of the afferent (sensory) cranial nerves schematically represented; lateral view. Image:Brain stem sagittal section.svg|Brain stem sagittal section </gallery> ==External links== * [http://sprojects.mmi.mcgill.ca/cns/histo/systems/cranialnerves/main.htm Diagrams at McGill] * [http://thalamus.wustl.edu/course/brstem.html Digram at Washington University] * {{UMichAtlas|n2a6p2}} * [http://www.coloradocollege.edu/idprog/Neuroscience/Cranial.html Slides at Colorado College] {{Cranial nerves}} {{Mesencephalon}} {{Medulla and pons of rhombencephalon}} [[Category:Neuroanatomy]]