Medial Eminence Of Floor Of Fourth Ventricle

	Medial Eminence Of Floor Of Fourth Ventricle In the human brain, the rhomboid fossa is divided into symmetrical halves by a median sulcus which reaches from the upper to the lower angles of the fossa and is deeper below than above. On either side of this sulcus is an elevation, the medial eminence, bounded laterally by a sulcus, the sulcus limitans. In the superior part of the fossa the medial eminence has a width equal to that of the corresponding half of the fossa, but opposite the superior fovea it forms an elongated swelling, the ''colliculus facialis'', which overlies the nucleus of the abducent nerve, and is, in part at least, produced by the internal genu of the facial nerve The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of tas .... References External links * https://web.archive.org/web/20081224022115/http://isc.temple.ed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Rhomboid Fossa The rhomboid fossa is a rhombus-shaped depression that is the anterior part of the fourth ventricle. Its anterior wall, formed by the back of the pons and the medulla oblongata, constitutes the floor of the fourth ventricle. It is covered by a thin layer of grey matter continuous with that of the spinal cord; superficial to this is a thin lamina of neuroglia which constitutes the ependyma of the ventricle and supports a layer of ciliated epithelium. Parts The fossa consists of three parts, superior, intermediate, and inferior: ;The superior part :The superior part is triangular in shape and limited laterally by the superior cerebellar peduncle; its apex, directed upward, is continuous with the cerebral aqueduct; its base is represented by an imaginary line at the level of the upper ends of the superior foveae. ;The intermediate part :The intermediate part extends from this level to that of the horizontal portions of the taeniae of the ventricle; it is narrow above where it is li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Nucleus Of The Abducent Nerve The abducens nucleus is the originating nucleus from which the abducens nerve (VI) emerges—a cranial nerve nucleus. This nucleus is located beneath the fourth ventricle in the caudal portion of the pons, medial to the sulcus limitans. The abducens nucleus along with the internal genu of the facial nerve make up the facial colliculus, a hump at the caudal end of the medial eminence on the dorsal aspect of the pons. Structure Two primary neuron types are located in the abducens nucleus: motorneurons and interneurons. The former directly drive the contraction of the ipsilateral lateral rectus muscle via the abducens nerve (sixth cranial nerve); contraction of this muscle rotates the eye outward (abduction). The latter relay signals from the abducens nucleus to the contralateral oculomotor nucleus, where motoneurons drive the contraction of the ipsilateral medial rectus muscle (hence, contralateral to the abducens nucleus that issues the command) ; contraction of this muscle rotate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Facial Nerve The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue. The nerve typically travels from the pons through the facial canal in the temporal bone and exits the skull at the stylomastoid foramen. It arises from the brainstem from an area posterior to the cranial nerve VI (abducens nerve) and anterior to cranial nerve VIII (vestibulocochlear nerve). The facial nerve also supplies preganglionic parasympathetic fibers to several head and neck ganglia. The facial and intermediate nerves can be collectively referred to as the nervus intermediofacialis. The path of the facial nerve can be divided into six segments: # intracranial (cisternal) segment # meatal (canalicular) segment (within the internal auditory canal) # labyrinthine segment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]