auditory nerve

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nerve

 [nerv]
a macroscopic cordlike structure of the body, comprising a collection of nerve fibers that convey impulses between a part of the central nervous system and some other body region. See Appendix 2-6 and see color plates.

Depending on their function, nerves are known as sensory, motor, or mixed. Sensory nerves, sometimes called afferent nerves, carry information from the outside world, such as sensations of heat, cold, and pain, to the brain and spinal cord. Motor nerves, or efferent nerves, transmit impulses from the brain and spinal cord to the muscles. Mixed nerves are composed of both motor and sensory fibers, and transmit messages in both directions at once.

Together, the nerves make up the peripheral nervous system, as distinguished from the central nervous system (brain and spinal cord). There are 12 pairs of cranial nerves, which carry messages to and from the brain. Spinal nerves arise from the spinal cord and pass out between the vertebrae; there are 31 pairs, 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. The various nerve fibers and cells that make up the autonomic nervous system innervate the glands, heart, blood vessels, and involuntary muscles of the internal organs.
Details of structure of components of nerve tissue.
accelerator n's the cardiac sympathetic nerves, which, when stimulated, accelerate the action of the heart.
acoustic nerve vestibulocochlear nerve; see anatomic Table of Nerves in the Appendices.
afferent nerve any nerve that transmits impulses from the periphery toward the central nervous system, such as a sensory nerve. See also neuron.
articular nerve any mixed peripheral nerve that supplies a joint and its associated structures.
auditory nerve vestibulocochlear nerve; see anatomic Table of Nerves in the Appendices.
autonomic nerve any nerve of the autonomic nervous system; called also visceral nerve.
cranial n's see cranial nerves.
cutaneous nerve any mixed peripheral nerve that supplies a region of the skin. See anatomic Table of Nerves in the Appendices.
depressor nerve
1. a nerve that lessens the activity of an organ.
2. an afferent nerve whose stimulation causes a fall in blood pressure.
efferent nerve any nerve that carries impulses from the central nervous system toward the periphery, such as a motor nerve. See also neuron.
excitor nerve one that transmits impulses resulting in an increase in functional activity.
excitoreflex nerve a visceral nerve that produces reflex action.
fusimotor n's those that innervate the intrafusal fibers of the muscle spindle.
gangliated nerve any nerve of the sympathetic nervous system.
inhibitory nerve one that transmits impulses resulting in a decrease in functional activity.
medullated nerve myelinated nerve.
mixed nerve (nerve of mixed fibers) a nerve composed of both sensory (afferent) and motor (efferent) fibers.
motor nerve a peripheral efferent nerve that stimulates muscle contraction.
myelinated nerve one whose axons are encased in a myelin sheath; called also medullated nerve.
peripheral nerve any nerve outside the central nervous system.
pilomotor n's those that supply the arrector muscles of hair.
pressor nerve an afferent nerve whose irritation stimulates a vasomotor center and increases intravascular tension.
sciatic nerve see sciatic nerve.
secretory nerve an efferent nerve whose stimulation increases vascular activity.
sensory nerve a peripheral nerve that conducts impulses from a sense organ to the spinal cord or brain. See also neuron.
somatic n's the sensory and motor nerves supplying skeletal muscle and somatic tissues.
spinal n's the 31 pairs of nerves arising from the spinal cord and passing out through the vertebrae; there are eight cervical, twelve thoracic, five lumbar, five sacral, and one coccygeal. , and see anatomic Table of Nerves in the Appendices.
Spinal nerves emerging from the spinal cord through the intervertebral foramina with muscles or muscle movements listed for specific levels. From McQuillan et al., 2002.
splanchnic n's those of the blood vessels and viscera, especially the visceral branches of the thoracic, abdominal (lumbar), and pelvic parts of the sympathetic trunks. See Appendix 3-5.
sudomotor n's those that innervate the sweat glands.
sympathetic n's
2. any nerve of the sympathetic nervous system.
trophic nerve one concerned with regulation of nutrition.
unmyelinated nerve one whose axons are not encased in a myelin sheath.
vasoconstrictor nerve one whose stimulation causes contraction of blood vessels.
vasodilator nerve one whose stimulation causes dilation of blood vessels.
vasomotor nerve one concerned in controlling the caliber of vessels, whether as a vasoconstrictor or vasodilator.
vasosensory nerve any nerve supplying sensory fibers to the vessels.
visceral nerve autonomic nerve.

co·chle·ar nerve

[TA]
the part of the vestibulocochlear nerve [CN VIII] peripheral to the cochlear root; composed of the central nerve processes of the bipolar neurons of the spiral ganglion, which have their peripheral processes on the four rows of neuroepithelial cells (hair cells) of the spiral organ.
See also: cochlear root of cranial nerve VIII.

auditory nerve

auditory nerve

auditory nerve

The cranial nerve which connects the inner ear to the brainstem, which contains sensory fibres for sound and vestibular fibres for balance.

coch·le·ar nerve

(kok'lē-ăr nĕrv) [TA]
The part of the vestibulocochlear nerve peripheral to the cochlear root. It is composed of fibers with central nerve processes that arise from the bipolar neurons of the spiral ganglion and that have their peripheral processes on the four rows of neuroepithelial cells (hair cells) of the spiral organ.
Synonym(s): auditory nerve.

auditory nerve

The acoustic or vestibulocochlear nerve. The 8th cranial nerve.

auditory nerve

the 8th cranial nerve. It carries sensory impulses from the inner ear.

auditory

pertaining to the ear or the sense of hearing.

auditory apparatus
comprises the tympanic membrane, the auditory ossicles that connect the membrane to the oval window to the internal ear, the membranous labyrinth and its contained endolymph, the labyrinth's cochlear duct, the organ of Corti, a specialized sensory epithelium lining the duct, the sensory hair cells of the organ of Corti and the sensory receptors of the auditory nerve that terminate at the base of the hair cells.
auditory bulb
the membranous labyrinth and cochlea.
auditory conditioning signals
sounds used to condition animals to certain procedures or events, such as gathering at the sound of a bell or trumpet, milking to the sound of a radio, whistle signals to a sheep dog.
external auditory meatus
air-filled tubular extension of the auricle leading to the eardrum.
internal auditory meatus
a canal in the petrous temporal bone that accommodates the VIIth and VIIIth cranial nerves.
auditory nerve
the eighth cranial nerve; called also vestibulocochlear nerve and acoustic nerve. See Table 14.
auditory ossicles
the malleus, incus and stapes, the three small bones of the tympanic cavity of the ear. They form a connecting bony system from the tympanic membrane to the oval window that is the opening to the internal ear.
auditory tube
the narrow channel connecting the nasopharynx to the middle ear. See also pharyngotympanic tube.