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Perlia's Nucleus
Perlia's nucleus, also known as nucleus of Perlia and abbreviated as NP, is a spindle-shaped Nucleus (neuroanatomy), nucleus located in the Midbrain, mesencephalon, a subdivision of the Edinger-Westphal nucleus situated between the right and left Oculomotor nucleus, oculomotor nuclei. It is implicated in parasympathetic oculomotor functions, possibly including input to the Iris (anatomy), iris and ciliary muscle, ciliary. Perlia's nucleus is believed to be a characteristic found exclusively in animals capable of binocular vision. Moreover, it might be an exclusive characteristic of humans, as indicated by a systematic study of monkey brains, where only 9% exhibited a clear midline group, potentially corresponding to the NP. In 1891, Perlia's nucleus was identified as a central mediator for the convergent movement of the eyes based on clinical findings in ophthalmospegias. It has also recently been attributed an important role in the upward movement or gaze of the eyes. Structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleus (neuroanatomy)
In neuroanatomy, a nucleus (: nuclei) is a cluster of neurons in the central nervous system, located deep within the cerebral hemispheres and brainstem. The neurons in one nucleus usually have roughly similar connections and functions. Nuclei are connected to other nuclei by tracts, the bundles (fascicles) of axons (nerve fibers) extending from the cell bodies. A nucleus is one of the two most common forms of nerve cell organization, the other being layered structures such as the cerebral cortex or cerebellar cortex. In anatomical sections, a nucleus shows up as a region of gray matter, often bordered by white matter. The vertebrate brain contains hundreds of distinguishable nuclei, varying widely in shape and size. A nucleus may itself have a complex internal structure, with multiple types of neurons arranged in clumps (subnuclei) or layers. The term "nucleus" is in some cases used rather loosely, to mean simply an identifiably distinct group of neurons, even if they are sprea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |