Membranous labyrinth

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Membranous labyrinth
Gray924.png
The membranous labyrinth.
Details
Artery Labyrinthine artery
Identifiers
Latin labyrinthus membranaceus
TA98 A15.3.03.059
TA2 6995
FMA 61022
Anatomical terminology

The membranous labyrinth is a collection of fluid filled tubes and chambers which contain the receptors for the senses of equilibrium and hearing. It is lodged within the bony labyrinth in the inner ear and has the same general form; it is, however, considerably smaller and is partly separated from the bony walls by a quantity of fluid, the perilymph.

In certain places, it is fixed to the walls of the cavity.

The membranous labyrinth contains fluid called endolymph. The walls of the membranous labyrinth are lined with distributions of the cochlear nerve, one of the two branches of the vestibulocochlear nerve. The other branch is the vestibular nerve.

Within the vestibule, the membranous labyrinth does not quite preserve the form of the bony labyrinth, but consists of two membranous sacs, the utricle, and the saccule.

The membranous labyrinth is also the location for the receptor cells found in the inner ear.

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<span class="mw-page-title-main">Cochlea</span> Snail-shaped part of inner ear involved in hearing

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<span class="mw-page-title-main">Utricle (ear)</span> Membranous labyrinth in the vestibule of ear

The utricle and saccule are the two otolith organs in the vertebrate inner ear. The word utricle comes from Latin uter 'leather bag'. The utricle and saccule are part of the balancing system in the vestibule of the bony labyrinth. They use small stones and a viscous fluid to stimulate hair cells to detect motion and orientation. The utricle detects linear accelerations and head-tilts in the horizontal plane.

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<span class="mw-page-title-main">Vestibular membrane</span> Membrane in the cochlea in the inner ear

The vestibular membrane, vestibular wall or Reissner's membrane is a membrane inside the cochlea of the inner ear. It separates the cochlear duct from the vestibular duct. It helps to transmit vibrations from fluid in the vestibular duct to the cochlear duct. Together with the basilar membrane, it creates a compartment in the cochlea filled with endolymph, which is important for the function of the spiral organ of Corti. It allows nutrients to travel from the perilymph to the endolymph of the membranous labyrinth. It may be damaged in Ménière's disease. It is named after the German anatomist Ernst Reissner.

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<span class="mw-page-title-main">Bony labyrinth</span> Bony structure of the inner ear

The bony labyrinth is the rigid, bony outer wall of the inner ear in the temporal bone. It consists of three parts: the vestibule, semicircular canals, and cochlea. These are cavities hollowed out of the substance of the bone, and lined by periosteum. They contain a clear fluid, the perilymph, in which the membranous labyrinth is situated.

<span class="mw-page-title-main">Crista ampullaris</span> Sensory organ in the inner ear

The crista ampullaris is the sensory organ of rotation. They are found in the ampullae of each of the semicircular canals of the inner ear, meaning that there are three pairs in total. The function of the crista ampullaris is to sense angular acceleration and deceleration.

<span class="mw-page-title-main">Vestibule of the ear</span> Central part of the bony labyrinth

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.

<span class="mw-page-title-main">Anatomical terms of bone</span>

Many anatomical terms descriptive of bone are defined in anatomical terminology, and are often derived from Greek and Latin. Bone in the human body is categorized into long bone, short bone, flat bone, irregular bone and sesamoid bone.

References

PD-icon.svgThis article incorporates text in the public domain from page 1051 of the 20th edition of Gray's Anatomy (1918)