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Spiral Lamina
The osseous spiral lamina is a bony shelf or ledge which projects from the modiolus into the interior of the bony canal of the cochlea, and, like the canal, takes two-and-three-quarter turns around the modiolus. It reaches about half-way toward the outer wall of the tube, and partially divides its cavity into two passages or scalae, of which the upper is named the scala vestibuli, while the lower is termed the scala tympani. Near the summit of the cochlea the lamina ends in a hook-shaped process, the hamulus laminae spiralis; this assists in forming the boundary of a small opening, the helicotrema, through which the two scalae communicate with each other. From the spiral canal of the modiolus numerous canals pass outward through the osseous spiral lamina as far as its free edge. In the lower part of the first turn a second bony lamina, the ''secondary spiral lamina'', projects inward from the outer wall of the bony tube; it does not, however, reach the primary osseous spiral la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cochlea
The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus (cochlea), modiolus. A core component of the cochlea is the organ of Corti, the sensory organ of hearing, which is distributed along the partition separating the fluid chambers in the coiled tapered tube of the cochlea. Etymology The name 'cochlea' is derived from the Latin word for ''snail shell'', which in turn is from the Greek language, Ancient Greek κοχλίας ''kokhlias'' ("snail, screw"), and from κόχλος ''kokhlos'' ("spiral shell") in reference to its coiled shape; the cochlea is coiled in mammals with the exception of monotremes. Structure The cochlea (: cochleae) is a spiraled, hollow, conical chamber of bone, in which waves propagate from the base (near the middle ear and the oval window) to the apex (the top or center of the spiral). The spiral canal of the cochlea is a section of the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustic Nerve
The vestibulocochlear nerve or auditory vestibular nerve, also known as the eighth cranial nerve, cranial nerve VIII, or simply CN VIII, is a cranial nerve that transmits sound and equilibrium (balance) information from the inner ear to the brain. Through olivocochlear fibers, it also transmits motor and modulatory information from the superior olivary complex in the brainstem to the cochlea. Structure The vestibulocochlear nerve consists mostly of bipolar neurons and splits into two large divisions: the cochlear nerve and the vestibular nerve. Cranial nerve 8, the vestibulocochlear nerve, goes to the middle portion of the brainstem called the pons (which then is largely composed of fibers going to the cerebellum). The 8th cranial nerve runs between the base of the pons and medulla oblongata (the lower portion of the brainstem). This junction between the pons, medulla, and cerebellum that contains the 8th nerve is called the cerebellopontine angle. The vestibulocochlear ner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modiolus (cochlea)
The modiolus is a conical shaped central axis in the cochlea. The modiolus consists of spongy bone and the cochlea turns approximately 2.75 times around the central axis in humans. The cochlear nerve, as well as spiral ganglion is situated inside it. The cochlear nerve conducts impulses from the receptors located within the cochlea. The picture shows the osseous labyrinth. The modiolus is not labeled; it's at the axis of the spiral of the cochlea The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus (cochlea), modiolus. A core component of the cochlea is the organ of Cort .... See also * Modiolus (other) References External links * http://www.univ-brest.fr/S_Commun/Biblio/ANATOMIE/Web_anat/Tete_Cou/Oreille/Modiolus.jpg * http://www.kumc.edu/instruction/medicine/anatomy/histoweb/eye_ear/ear01.htm Ear {{Anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scala Vestibuli
The vestibular duct or scala vestibuli is a perilymph-filled cavity inside the cochlea of the inner ear that conducts sound vibrations to the cochlear duct. It is separated from the cochlear duct by Reissner's membrane and extends from the vestibule of the ear to the helicotrema where it joins the tympanic duct. Additional images Image:Gray923.png, The cochlea and vestibule, viewed from above. Image:Gray903.png, Transverse section of the cochlear duct of a fetal cat. Image:Right_osseous_labyrinth_interior_svg_hariadhi.svg, Interior of right osseous labyrinth. Image:Gray928.png, Diagrammatic longitudinal section of the cochlea. See also *Tympanic duct References internal websites Slidefrom University of Kansas Diagramat Indiana University – Purdue University Indianapolis Indiana ( ) is a state in the Midwestern region of the United States. It borders Lake Michigan to the northwest, Michigan to the north and northeast, Ohio to the east, the Ohio River and Ken ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scala Tympani
The tympanic duct or scala tympani is one of the perilymph-filled cavities in the inner ear of humans. It is separated from the cochlear duct by the basilar membrane, and it extends from the round window to the helicotrema, where it continues as vestibular duct. The purpose of the perilymph-filled tympanic duct and vestibular duct is to transduce the movement of air that causes the tympanic membrane and the ossicles to vibrate causing movement of liquid and the basilar membrane. This movement is conveyed to the organ of Corti inside the cochlear duct, composed of hair cells attached to the basilar membrane and their stereocilia embedded in the tectorial membrane. The movement of the basilar membrane compared to the tectorial membrane causes the stereocilia to bend. They then depolarise and send impulses to the brain via the cochlear nerve. This produces the sensation of sound. Additional images File:Right_osseous_labyrinth_interior_svg_hariadhi.svg, Interior of right osseous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hamulus Laminae Spiralis
A hamus or hamulus is a structure functioning as, or in the form of, hooks or hooklets. Etymology The terms are directly from Latin, in which ''hamus'' means "hook". The plural is ''hami''. ''Hamulus'' is the diminutive – hooklet or little hook. The plural is ''hamuli''. Adjectives are ''hamate'' and ''hamulate'', as in "a hamulate wing-coupling", in which the wings of certain insects in flight are joined by hooking hamuli on one wing into folds on a matching wing. ''Hamulate'' can also mean "having hamuli". The terms ''hamose'', ''hamular'', ''hamous'' and ''hamiform'' also have been used to mean "hooked", or "hook-shaped". Terms such as ''hamate'' that do not indicate a diminutive usually refer particularly to a hook at the tip, whereas diminutive terms such as ''hamulose'' tend to imply that something is beset with small hooks. Anatomy In vertebrate anatomy, a hamulus is a small, hook-shaped portion of a bone, or possibly of other hard tissue. In human anatomy, example ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicotrema
The helicotrema (from elixmeaning coil and rēmameaning hole) is the part of the cochlear labyrinth where the scala tympani and the scala vestibuli meet. It is the main component of the cochlear apex. The hair cells near this area best detect low frequency sounds. Structure The helicotrema is a part of the cochlear labyrinth where the scala tympani and the scala vestibuli meet. It is the main component of the cochlear apex. Function The helicotrema connects the scala tympani and the scala vestibuli. This allows fluid to move between the two. It slightly impedes the travel of sound. The hair cells near this area best detect low frequency sounds. Clinical significance The hair cells near the helicotrema are at higher risk of acoustic trauma than those in most other parts of the cochlea. It is also important during ear surgery. When pressure is placed on the perilymph in the cochlea, it reduces pressure and prevents damage to the organ of Corti The organ of Corti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Spiral Lamina
Secondary may refer to: Science and nature * Secondary emission, of particles ** Secondary electrons, electrons generated as ionization products * The secondary winding, or the electrical or electronic circuit connected to the secondary winding in a transformer * Secondary (chemistry), a term used in organic chemistry to classify various types of compounds * Secondary color, color made from mixing primary colors * Secondary mirror, second mirror element/focusing surface in a reflecting telescope * Secondary craters, often called "secondaries" * Secondary consumer, in ecology * An antiquated name for the Mesozoic in geosciences * Secondary feathers, flight feathers attached to the ulna on the wings of birds Society and culture * Secondary (football), a position in American football and Canadian football * Secondary dominant in music * Secondary education, education which typically takes place after six years of primary education ** Secondary school, the type of school at the sec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestibule Fissure
Vestibule or vestibulum can have the following meanings, each primarily based upon a common origin, from early 17th century French, derived from Latin ''vestibulum, -i n.'' "entrance court". Architecture * an entryway * a lobby, entrance hall, or passage between the outer door and the interior of a building *a porch * an enclosed area between two railroad cars * a reception area * an antechamber * an entry room * a passageway acting as an airlock between two environments Related: * a covered section between the outer opening and inner opening of a tent, typically used for the storage of boots, packs and small equipment Anatomy In general, vestibule is a small space or cavity at the beginning of a canal. * The vulval vestibule is a part of the vulva between the labia minora into which the urinary meatus (urethral opening) and the vaginal opening are situated * The nasal vestibule is the nostrils, simply lined with an extension of skin epithelium, in contrast to nasal cavity, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basilar Membrane
The basilar membrane is a stiff structural element within the cochlea of the inner ear which separates two liquid-filled tubes that run along the coil of the cochlea, the scala media and the scala tympani. The basilar membrane moves up and down in response to incoming sound waves, which are converted to traveling waves on the basilar membrane. Structure The basilar membrane is a pseudo-resonant structure that, like the strings on an instrument, varies in width and stiffness. But unlike the parallel strings of a guitar, the basilar membrane is not a discrete set of resonant structures, but a single structure with varying width, stiffness, mass, damping, and duct dimensions along its length. The motion of the basilar membrane is generally described as a traveling wave. The properties of the membrane at a given point along its length determine its characteristic frequency (CF), the frequency at which it is most sensitive to sound vibrations. The basilar membrane is widest (0.42 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
