Pons 229296 220932168 2008-06-22T07:51:02Z Gimme danger 1659342 /* Anatomy of the pons */ rm unnecessary parens {{Infobox Brain| Name = {{PAGENAME}} | GraySubject = 187 | GrayPage = 785 | Image = Gray768.png | Caption = Diagram showing the positions of the three principal subarachnoid cisternæ. (Pons visible at center.) | Image2 = Gray679.png | Caption2 = [[Terms for anatomical location|Anteroinferior view]] of the '''medulla oblongata''' and [[pons]]. | IsPartOf = [[Brain stem]]| Components = | Artery = [[pontine arteries]] | Vein = | BrainInfoType = hier | BrainInfoNumber = 538 | MeshName = Pons | MeshNumber = A08.186.211.132.810.428.600 | }} {{otheruses}} The '''pons''' (sometimes '''pons Varolii''' after [[Costanzo Varolio]]) is a structure located on the [[brain stem]]. It is [[rostral]] to the [[medulla oblongata]], [[caudal]] to the [[midbrain]], and [[ventral]] to the [[cerebellum]]. In [[human]]s and other [[biped]]s this means it is above the medulla, below the midbrain, and [[anterior]] to the cerebellum. ==Function== The pons [[relay]]s [[sense|sensory]] [[information]] between the [[cerebellum]] and [[telencephalon|cerebrum]]; aids in relaying other messages in the brain; controls arousal, and regulates respiration (see [[respiratory centres]]). In some theories, the pons has a role in [[dream]]ing.<ref>[http://www.neurontic.com/2006/07/science-of-dreaming.html The "Science of Dreaming" in Neurontic: Psychology for the Modern Mind.].</ref> ==Anatomy of the pons== The "knob-like" process (Basal pons) is 2 centimeters long and located on the anterior (front) of the brainstem. It is formed of nerves that travel from one side (left or right) to the other. Most other fibres in the brainstem travel up and down. The posterior (back) surface of the pons forms part of the wall of the [[fourth ventricle]] of the brain. Most blood to the pons is supplied by [[pontine arteries]]. These are small arteries that branch off the [[basilar artery]] of the [[Circle of Willis]]. Blood also comes from the [[anterior inferior]], and [[superior cerebellar]] arteries. There are two main domains in the pons for [[control of respiration]]:<ref>{{GeorgiaPhysiology|4/4ch6/s4ch6_10}}</ref> * the [[apneustic center]] - lower pons * the [[pneumotaxic center]] - upper pons ==Cranial nerve nuclei== A number of [[cranial nerve]] nuclei are present in the pons: * mid-pons: The ''chief'' or ''pontine'' nucleus of the [[trigeminal nerve]] sensory nucleus (V) * mid-pons: the [[motor nucleus for the trigeminal nerve]] (V) * lower down in the pons: [[abducens nucleus]] (VI) * lower down in the pons: [[facial nerve nucleus]] (VII) * lower down in the pons: [[Vestibulocochlear nerve|vestibulocochlear]] nuclei ([[vestibular nuclei]] and [[cochlear nuclei]]) (VIII) ==Related diseases== * [[Central pontine myelinosis]], a [[demyelination]] disease that causes difficulty with sense of balance, walking, sense of touch, swallowing and speaking to mention just a few symptoms. In a clinical setting it is often associated with transplant. Undiagnosed it can lead to death or 'locked in' syndrome. ==Additional images== <gallery> Image:Gray677.png|Scheme showing the connections of the several parts of the brain. Image:Gray682.png|Superficial dissection of brain-stem. Lateral view. Image:Gray689.png|Superficial dissection of brain-stem. Ventral view. Image:Gray701.png|Coronal section of the pons, at its upper part. Image:Gray705.png|Dissection showing the projection fibers of the cerebellum. Image:Gray707.png|Sagittal section through right cerebellar hemisphere. The right olive has also been cut sagitally. Image:Gray708.svg|Scheme of roof of fourth ventricle. The arrow is in the foramen of Majendie. Image:Gray715.png|Mesal aspect of a brain sectioned in the median sagittal plane. Image:Gray717.png|Coronal section of brain immediately in front of pons. Image:Gray719.png|Hind- and mid-brains; postero-lateral view. Image:Gray720.png|Median sagittal section of brain. Image:Gray745.png|Dissection showing the course of the cerebrospinal fibers. Image:Gray760.png|Terminal nuclei of the cochlear nerve, with their upper connections. Image:Gray761.png|Terminal nuclei of the vestibular nerve, with their upper connections. Image:Gray1180.png|The [[hypophysis cerebri]] in position. Shown in [[sagittal]] section. Image:Illu pituitary pineal glands.jpg|Pituitary and pineal glands Image:Brainstem Abducens.png|Axial section of the Brainstem (Pons) at the level of the Facial Colliculus Image:Human cerebrum lateral view, a part of temporal lobe resected description.JPG|Human cerebrum lateral view Image:Human brain frontal (coronal) section description.JPG|Human brain frontal (coronal) section Image:Human brainstem anterior view 2 description.JPG|Human brainstem anterior view </gallery> ==References== <references/> ==External links== * [http://faculty.ucc.edu/biology-potter/The_Brain/sld017.htm Diagram at UCC] * {{BrainMaps|Pons}} {{Rhombencephalon}} [[Category:Brainstem]] [[Category:Neuroanatomy]] [[cs:Varolův most]] [[da:Pons]] [[de:Pons]] [[es:Puente troncoencefálico]] [[fr:Pont de Varole]] [[it:Ponte di Varolio]] [[lt:Tiltas (smegenys)]] [[nl:Pons (hersenen)]] [[ja:橋 (脳)]] [[pl:Most (mózg)]] [[pt:Ponte (sistema nervoso)]] [[ru:Варолиев мост]] [[sk:Varolov most]] [[sr:Варолијев мост]] [[fi:Aivosilta]] [[tr:Pons]]