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Lagena (anatomy)
The lagena (from Greek λάγηνος : lágēnos for flask) is a structure found in humans and in animals. In human anatomy In the ear, the extremities of the ductus cochlearis are closed; the upper is termed the lagena and is attached to the cupula at the upper part of the helicotrema; the lower is lodged in the recessus cochlearis of the vestibule. In fish and amphibians The lagena is part of the vestibular system in fish and amphibians. It contains the otolith An otolith ( grc-gre, ὠτο-, ' ear + , ', a stone), also called statoconium or otoconium or statolith, is a calcium carbonate structure in the saccule or utricle of the inner ear, specifically in the vestibular system of vertebrates. The sa ...s ''asterisci''. In fish, the lagena is implicated in hearing and the registration of vertical linear acceleration,Webb, Jacqueline F./Richard R. Fay/Arthur N. Popper (Eds.): ''Fish Bioacoustics'', Springer, 2008, p. 23. in amphibians is the latter only. References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ductus Cochlearis
The cochlear duct (bounded by the scala media) is an endolymph filled cavity inside the cochlea, located between the tympanic duct and the vestibular duct, separated by the basilar membrane and the vestibular membrane (Reissner's membrane) respectively. The cochlear duct houses the organ of Corti. Structure The cochlear duct is part of the cochlea. It is separated from the tympanic duct (scala tympani) by the basilar membrane. It is separated from the vestibular duct (scala vestibuli) by the vestibular membrane (Reissner's membrane). The stria vascularis is located in the wall of the cochlear duct. Development The cochlear duct develops from the ventral otic vesicle (otocyst). It grows slightly flattened between the middle and outside of the body. This development may be regulated by the genes EYA1, SIX1, GATA3, and TBX1. The organ of Corti develops inside the cochlear duct. Function The cochlear duct contains the organ of Corti. This is attached to the basilar membrane. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cochlear Cupula
The cochlear cupula is a structure in the cochlea. It is the apex of the cochlea. The bony canal 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. A core component of the cochlea is the Organ of Corti, the sensory or ... takes two and three-quarter turns around the modiolus. The modiolus is about 30 mm in length, and diminishes gradually in diameter from the base to the summit, where it terminates in the cupula. Auditory system {{anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicotrema
The helicotrema (from el, ἕλιξ 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. Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestibule Of The Ear
The vestibule is the central part of the bony labyrinth in the inner ear, and is situated medial to the eardrum, behind the cochlea, and in front of the three semicircular canals. The name comes from the Latin ', literally an entrance hall. Structure The vestibule is somewhat oval in shape, but flattened transversely; it measures about 5 mm from front to back, the same from top to bottom, and about 3 mm across. In its lateral or tympanic wall is the oval window, closed, in the fresh state, by the base of the stapes and annular ligament. On its medial wall, at the forepart, is a small circular depression, the recessus sphæricus, which is perforated, at its anterior and inferior part, by several minute holes (macula cribrosa media) for the passage of filaments of the acoustic nerve to the saccule; and behind this depression is an oblique ridge, the crista vestibuli, the anterior end of which is named the pyramid of the vestibule. This ridge bifurcates below to enclose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestibular System
The vestibular system, in vertebrates, is a sensory system that creates the sense of balance and spatial orientation for the purpose of coordinating movement with balance. Together with the cochlea, a part of the auditory system, it constitutes the labyrinth of the inner ear in most mammals. As movements consist of rotations and translations, the vestibular system comprises two components: the semicircular canals, which indicate rotational movements; and the otoliths, which indicate linear accelerations. The vestibular system sends signals primarily to the neural structures that control eye movement; these provide the anatomical basis of the vestibulo-ocular reflex, which is required for clear vision. Signals are also sent to the muscles that keep an animal upright and in general control posture; these provide the anatomical means required to enable an animal to maintain its desired position in space. The brain uses information from the vestibular system in the head and fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otolith
An otolith ( grc-gre, ὠτο-, ' ear + , ', a stone), also called statoconium or otoconium or statolith, is a calcium carbonate structure in the saccule or utricle of the inner ear, specifically in the vestibular system of vertebrates. The saccule and utricle, in turn, together make the ''otolith organs''. These organs are what allows an organism, including humans, to perceive linear acceleration, both horizontally and vertically (gravity). They have been identified in both extinct and extant vertebrates. Counting the annual growth rings on the otoliths is a common technique in estimating the age of fish. Description Endolymphatic infillings such as otoliths are structures in the saccule and utricle of the inner ear, specifically in the vestibular labyrinth of all vertebrates (fish, amphibians, reptiles, mammals and birds). In vertebrates, the saccule and utricle together make the ''otolith organs''. Both statoconia and otoliths are used as gravity, balance, movement, and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
