vestibular nerve

(noun)

One of the two branches of the vestibulocochlear nerve (the cochlear nerve being the other). It connects to the semicircular canals via the vestibular ganglion and receives positional information.

Related Terms

Examples of vestibular nerve in the following topics:

  • Vestibulocochlear (VIII) Nerve

    • The vestibulocochlear nerve (also known as the auditory vestibular nerve and cranial nerve VIII) has axons that carry the modalities of hearing and equilibrium.
    • It consists of the cochlear nerve that carries information about hearing, and the vestibular nerve that carries information about balance.
    • The vestibulocochlear nerve consists mostly of bipolar neurons and splits into two large divisions: the cochlear nerve and the vestibular nerve.
    • The vestibular nerve travels from the vestibular system of the inner ear.
    • An illustration of the inner ear showing its semicircular canal, hair cells, ampulla, cupula, vestibular nerve, and fluid.

  • Sensory Modalities

    • A message is sent to a neuron called the bipolar cell through the use of a nerve impulse.
    • The organ of equilibrioception is the vestibular labyrinthine system found in both of the inner ears.
    • The vestibular nerve conducts information from sensory receptors in three ampulla, each of which sense fluid motion in three semicircular canals caused by a three-dimensional rotation of the head.
    • The vestibular nerve also conducts information from the utricle and the saccule; these contain hair-like sensory receptors that bend under the weight of otoliths (small crystals of calcium carbonate) that provide the inertia needed to detect head rotation, linear acceleration, and the direction of gravitational force.
    • Nociception (physiological pain) signals nerve or other tissue damage.

  • Balance and Determining Equilibrium

    • With hair cells in the inner ear that sense linear and rotational motion, the vestibular system determines equilibrium and balance states.
    • The neural signals generated in the vestibular ganglion are transmitted through the vestibulocochlear nerve to the brain stem and cerebellum.
    • Together, these components make up the vestibular system.
    • By comparing the relative movements of both the horizontal and vertical ampullae, the vestibular system can detect the direction of most head movements within three-dimensional (3-D) space.

  • The Vestibular System

    • The vestibular system has some similarities with the auditory system.
    • Together, they make up what is known as the vestibular labyrinth .
    • It is the vestibular branch of the vestibulocochlear cranial nerve that deals with balance.
    • The structure of the vestibular labyrinth is made up of five vestibular receptor organs in the inner ear: the utricle, the saccule, and three semicircular canals.
    • Identify the structures of the vestibular system that respond to gravity

  • Pons

    • The alar plate produces sensory neuroblasts, which will give rise to the solitary nucleus and its special visceral afferent column, the cochlear and vestibular nuclei (which form the special somatic afferent fibers of the vestibulocochlear nerve), the spinal and principal trigeminal nerve nuclei (which form the general somatic afferent column of the trigeminal nerve), and the pontine nuclei, which is involved in motor activity.
    • Basal plate neuroblasts give rise to the abducens nucleus (forms the general somatic efferent fibers), the facial and motor trigeminal nuclei (form the special visceral efferent column), and the superior salivatory nucleus, which forms the general visceral efferent fibers of the facial nerve.
    • A number of cranial nerve nuclei are present in the pons:
    • The chief or pontine nucleus of the trigeminal nerve sensory nucleus (V)- mid-pons
    • The functions of the four nerves of the pons include sensory roles in hearing, equilibrium, taste, and facial sensations such as touch and pain.

  • Functions of the Brain Stem

    • The brainstem gives rise to cranial nerves 3 through 12 and provides the main motor and sensory innervation to the face and neck via the cranial nerves.
    • Though small, it is an extremely important part of the brain, as the nerve connections of the motor and sensory systems from the main part of the brain that communicate with the peripheral nervous system pass through the brainstem.
    • In addition, upper motor neurons originate in the brain stem's vestibular, red, tectal, and reticular nuclei, which also descend and synapse in the spinal cord.
    • Cranial nerves are nerves that emerge directly from the brain, in contrast to spinal nerves, which emerge from segments of the spinal cord.
    • In humans, there are traditionally twelve pairs of cranial nerves.

  • Introduction to Sensation

    • Two other senses, kinesthesia and the vestibular senses, have become widely recognized by scientists.
    • Vestibular senses detect gravity, linear acceleration (such as speeding up or slowing down on a straight road), and rotary acceleration (such as speeding up or slowing down around a curve).
    • Both kinesthesia and the vestibular senses help us to  balance.
    • The amount of cortex devoted to any given body region is proportional to how many nerves are in that region, not to the region's physical size.
    • The resulting image is that of a distorted human body with disproportionately huge hands, lips, and face (because those regions have huge numbers of nerve endings).

  • Reception

    • Vestibular sensation, which is an organism's sense of spatial orientation and balance, proprioception (position of bones, joints, and muscles), and the sense of limb position that is used to track kinesthesia (limb movement) are part of somatosensation.
    • In the second type of sensory transduction, a sensory nerve ending responds to a stimulus in the internal or external environment; this neuron constitutes the sensory receptor.
    • Free nerve endings can be stimulated by several different stimuli, thus showing little receptor specificity.
    • This scheme shows the flow of information from the eyes to the central connections of the optic nerves and optic tracts, to the visual cortex.

  • Development of Hearing and Balance

    • Critical periods have been identified for the development of the hearing and vestibular system.
    • The vestibular wall will separate the cochlear duct from the perilymphatic scala vestibuli, a cavity inside the cochlea.
    • Critical periods have been identified for the development of hearing and the vestibular system.
    • Animals with abnormal vestibular development tend to have irregular motor skills.
    • Studies have consistently shown that animals with genetic vestibular deficiencies during this critical period have altered vestibular phenotypes, most likely as a result of lack insufficient input from the semicircular canals and dopaminergic abnormalities.

  • Female Reproductive Anatomy

    • Among the external structures are the vulva, which consists of the mons pubis, clitoris, labia majora, labia minora, and the vestibular glands.
    • The clitoris is a structure with erectile tissue that contains a large number of sensory nerves and serves as a source of stimulation during intercourse.
    • The greater vestibular glands are found at the sides of the vaginal opening and provide lubrication during intercourse.
    • An ovary consists of a medulla and cortex: the medulla contains nerves and blood vessels to supply the cortex with nutrients and remove waste.