Search results
Results from the WOW.Com Content Network
The semicircular canals are a component of the bony labyrinth that are at right angles from each other and contain their respective semicircular duct. At one end of each of the semicircular ducts is a dilated sac called a membranous ampulla, which is more than twice the diameter of the ducts.
Information from the semicircular canals reflects rotational movement of the head. Both are necessary for the sensation of body position and gaze stability in relation to a moving environment. Axons of the vestibular nerve synapse in the vestibular nucleus are found on the lateral floor and wall of the fourth ventricle in the pons and medulla.
The receptor cells located in the semicircular ducts are innervated by the eighth cranial nerve, the vestibulocochlear nerve (specifically the vestibular portion). The crista ampullaris itself is a cone-shaped structure, covered in receptor cells called "hair cells".
The bony labyrinth (also osseous labyrinth or otic capsule) 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.
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. [ 1 ] The name comes from the Latin vestibulum , literally an entrance hall.
Movement of fluid within the horizontal semicircular canal corresponds to rotation of the head around a vertical axis (i.e. the neck), as when doing a pirouette. The anterior and posterior semicircular canals detect rotations of the head in the sagittal plane (as when nodding), and in the frontal plane, as when cartwheeling. Both anterior and ...
Perilymph is the fluid contained within the bony labyrinth, surrounding and protecting the membranous labyrinth; perilymph resembles extracellular fluid in composition (sodium salts are the predominant positive electrolyte) and, via the cochlear aqueduct (sometimes referred to as the "perilymphatic duct"), is in continuity with cerebrospinal fluid.
Hearing: Cochlear duct: fluid waves in the endolymph of the cochlear duct stimulate the receptor cells, which in turn translate their movement into nerve impulses that the brain perceives as sound. Balance: Semicircular canals : angular acceleration of the endolymph in the semicircular canals stimulate the vestibular receptors of the endolymph.