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Ascending Tract Of Deiter's
The lateral vestibular nucleus (Deiters's nucleus) is the continuation upward and lateralward of the principal nucleus, and in it terminate many of the ascending branches of the vestibular nerve. Structure It consists of very large multipolar cells whose axons form an important part of the posterior longitudinal bundle (aka medial longitudinal fasciculus) of the same and the opposite side. The axons bifurcate as they enter the posterior longitudinal bundle, * the ''ascending branches'' send terminals and collaterals to the motor nuclei of the abducens, trochlear and oculomotor nerves via the ascending component of the medial longitudinal fasciculus, and are concerned in coördinating the movements of the eyes with alterations in the position of the head; * the ''descending branches'' pass down in the posterior longitudinal bundle into the anterior funiculus of the spinal cord as the vestibulospinal fasciculus (anterior marginal bundle) and are distributed to motor nuclei of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cochlear Nerve
The cochlear nerve (also auditory nerve or acoustic nerve) is one of two parts of the vestibulocochlear nerve, a cranial nerve present in amniotes, the other part being the vestibular nerve. The cochlear nerve carries auditory sensory information from the cochlea of the inner ear directly to the brain. The other portion of the vestibulocochlear nerve is the vestibular nerve, which carries spatial orientation information to the brain from the semicircular canals, also known as semicircular ducts. Anatomy and connections In terms of anatomy, an auditory nerve fiber is either bipolar or unipolar, with its distal projection being called the peripheral process, and its proximal projection being called the axon; these two projections are also known as the "peripheral axon" and the "central axon", respectively. The peripheral process is sometimes referred to as a dendrite, although that term is somewhat inaccurate. Unlike the typical dendrite, the peripheral process generates and cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Principal Nucleus
Principal may refer to: Title or rank * Principal (academia), the chief executive of a university ** Principal (education), the office holder/ or boss in any school * Principal (civil service) or principal officer, the senior management level in the UK Civil Service * Principal dancer, the top rank in ballet * Principal (music), the top rank in an orchestra Law * Principal (commercial law), the person who authorizes an agent ** Principal (architecture), licensed professional(s) with ownership of the firm * Principal (criminal law), the primary actor in a criminal offense * Principal (Catholic Church), an honorific used in the See of Lisbon Places * Principal, Cape Verde, a village * Principal, Ecuador, a parish Media * ''The Principal'' (TV series), a 2015 Australian drama series * ''The Principal'', a 1987 action film * Principal (music), the lead musician in a section of an orchestra * Principal photography, the first phase of movie production * "The Principal", a song o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equilibratory
The sense of balance or equilibrioception is the perception of balance and spatial orientation. It helps prevent humans and nonhuman animals from falling over when standing or moving. Equilibrioception is the result of a number of sensory systems working together; the eyes (visual system), the inner ears ( vestibular system), and the body's sense of where it is in space (proprioception) ideally need to be intact. The vestibular system, the region of the inner ear where three semicircular canals converge, works with the visual system to keep objects in focus when the head is moving. This is called the vestibulo-ocular reflex (VOR). The balance system works with the visual and skeletal systems (the muscles and joints and their sensors) to maintain orientation or balance. Visual signals sent to the brain about the body's position in relation to its surroundings are processed by the brain and compared to information from the vestibular and skeletal systems. Vestibular system In th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Marginal Bundle
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestibulospinal Fasciculus
The vestibulospinal tract is a neural tract in the central nervous system. Specifically, it is a component of the extrapyramidal system and is classified as a component of the medial pathway. Like other descending motor pathways, the vestibulospinal fibers of the tract relay information from nuclei to motor neurons. The vestibular nuclei receive information through the vestibulocochlear nerve about changes in the orientation of the head. The nuclei relay motor commands through the vestibulospinal tract. The function of these motor commands is to alter muscle tone, extend, and change the position of the limbs and head with the goal of supporting posture and maintaining balance of the body and head. Classification The vestibulospinal tract is part of the "extrapyramidal system" of the central nervous system. In human anatomy, the extrapyramidal system is a neural network located in the brain that is part of the motor system involved in the coordination of movement. The system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinal Cord
The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spinal cord, which contains cerebrospinal fluid. The brain and spinal cord together make up the central nervous system (CNS). In humans, the spinal cord begins at the occipital bone, passing through the foramen magnum and then enters the spinal canal at the beginning of the cervical vertebrae. The spinal cord extends down to between the first and second lumbar vertebrae, where it ends. The enclosing bony vertebral column protects the relatively shorter spinal cord. It is around long in adult men and around long in adult women. The diameter of the spinal cord ranges from in the cervical and lumbar regions to in the thoracic area. The spinal cord functions primarily in the transmission of nerve signals from the motor cortex to the body, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Funiculus
In the spinal cord, the most lateral of the bundles of the ventral nerve roots is generally taken as a dividing line that separates the antero-lateral region into two parts: an anterior funiculus (or anterior column), between the anterior median fissure and the most lateral of the ventral nerve roots; and a lateral funiculus The most lateral of the bundles of the anterior nerve roots is generally taken as a dividing line that separates the anterolateral system into two parts. These are the anterior funiculus, between the anterior median fissure and the most lateral ..., between the exit of these roots and the posterolateral sulcus. References Central nervous system {{Neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oculomotor Nerve
The oculomotor nerve, also known as the third cranial nerve, cranial nerve III, or simply CN III, is a cranial nerve that enters the orbit through the superior orbital fissure and innervates extraocular muscles that enable most movements of the eye and that raise the eyelid. The nerve also contains fibers that innervate the intrinsic eye muscles that enable pupillary constriction and accommodation (ability to focus on near objects as in reading). The oculomotor nerve is derived from the basal plate of the embryonic midbrain. Cranial nerves IV and VI also participate in control of eye movement. Structure The oculomotor nerve originates from the third nerve nucleus at the level of the superior colliculus in the midbrain. The third nerve nucleus is located ventral to the cerebral aqueduct, on the pre-aqueductal grey matter. The fibers from the two third nerve nuclei located laterally on either side of the cerebral aqueduct then pass through the red nucleus. From the red nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trochlear Nerve
The trochlear nerve (), ( lit. ''pulley-like'' nerve) also known as the fourth cranial nerve, cranial nerve IV, or CN IV, is a cranial nerve that innervates just one muscle: the superior oblique muscle of the eye, which operates through the pulley-like trochlea. CN IV is a motor nerve only (a somatic efferent nerve), unlike most other CNs. The trochlear nerve is unique among the cranial nerves in several respects: * It is the ''smallest'' nerve in terms of the number of axons it contains. * It has the greatest intracranial length. * It is the only cranial nerve that exits from the dorsal (rear) aspect of the brainstem. * It innervates a muscle, the superior oblique muscle, on the opposite side (contralateral) from its nucleus. The trochlear nerve decussates within the brainstem before emerging on the contralateral side of the brainstem (at the level of the inferior colliculus). An injury to the trochlear nucleus in the brainstem will result in an contralateral superior obliqu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abducens
The abducens nerve or abducent nerve, also known as the sixth cranial nerve, cranial nerve VI, or simply CN VI, is a cranial nerve in humans and various other animals that controls the movement of the lateral rectus muscle, one of the extraocular muscles responsible for outward Gaze (physiology), gaze. It is a Somatic (biology), somatic efferent nerve fiber, efferent nerve. Structure Nucleus The abducens nucleus is located in the pons, on the floor of the fourth ventricle, at the level of the facial colliculus. Axons from the facial nerve loop around the abducens nucleus, creating a slight bulge (the facial colliculus) that is visible on the dorsal surface of the floor of the fourth ventricle. The abducens nucleus is close to the midline, like the other motor nuclei that control eye movements (the Oculomotor nucleus, oculomotor and Trochlear nucleus, trochlear nuclei). Motor axons leaving the abducens nucleus run ventrally and caudally through the pons. They pass lateral to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motor Nuclei
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power generation), heat energy (e.g. geothermal), chemical energy, electric potential and nuclear energy (from nuclear fission or nuclear fusion). Many of these processes generate heat as an intermediate energy form, so heat engines have special importance. Some natural processes, such as atmospheric convection cells convert environmental heat into motion (e.g. in the form of rising air currents). Mechanical energy is of particular importance in transportation, but also plays a role in many industrial processes such as cutting, grinding, crushing, and mixing. Mechanical heat engines convert heat into work via various thermodynamic processes. The internal combustion engine is perhaps the most common example of a mechanical heat engine, in which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medial Longitudinal Fasciculus
The medial longitudinal fasciculus (MLF) is an area of crossed over tracts, on each side of the brainstem. These bundles of axons are situated near the midline of the brainstem. They are made up of both ascending and descending fibers that arise from a number of sources and terminate in different areas, including the superior colliculus, the vestibular nuclei, and the cerebellum. It contains the interstitial nucleus of Cajal, responsible for oculomotor control, head posture, and vertical eye movement. The medial longitudinal fasciculus is the main central connection for the oculomotor nerve, trochlear nerve, and abducens nerve. It carries information about the direction that the eyes should move. Lesions of the medial longitudinal fasciculus can cause nystagmus and diplopia, which may be associated with multiple sclerosis, a neoplasm, or a stroke. Structure The medial longitudinal fasciculus is an area of crossed over tracts, on each side of the brainstem. It is medial, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
