Which nerve is the auditory nerve?

The acoustic or cochlear nerve is a sensory nerve essential for hearing. Together with the cochlea and the central pathway from the nucleus in the pons to the temporal cortex, it is part of the auditory system.

Is there an auditory nerve?

Auditory nervous system: The auditory nerve runs from the cochlea to a station in the brainstem (known as nucleus). From that station, neural impulses travel to the brain – specifically the temporal lobe where sound is attached meaning and we HEAR.

What number is the auditory nerve?

The vestibulocochlear nerve (auditory vestibular nerve), known as the eighth cranial nerve, transmits sound and equilibrium (balance) information from the inner ear to the brain.

Is auditory nerve sensory nerve?

The cochlear nerve, also known as the acoustic nerve, is the sensory nerve that transfers auditory information from the cochlea (auditory area of the inner ear) to the brain. It is one of the many pieces that make up the auditory system, which enables effective hearing.

Where are the auditory nerves located?

The cochlear nerve, also known as the acoustic or auditory nerve, is the cranial nerve responsible for hearing. It travels from the inner ear to the brainstem and out through a bone located on the side of the skull called the temporal bone.

What is the auditory nerve function?

The auditory nerve is a bundle of nerve fibres that carry information between the cochlea in the inner ear and the brain. The function of the auditory nerve is to transmit signals from the internal ear to the brain.

What stimulates the auditory nerve?

Spiral ganglion neurons innervating the hair bundles respond by firing action potentials. The spiral ganglion cells give rise to the auditory nerve fibers that constitute the auditory nerve, which transmits these action potentials to the brain. Sensorineural hearing loss results from damage to the inner ear.

Which nerve connects the ear to the brain?

Also known as the vestibulocochlear nerve, it connects the inner ear with the brain and has two different parts. One part is involved in transmitting sound, the other helps send balance information from the inner ear to the brain.

What is 7th cranial nerve?

A nerve that runs from the brainstem, through openings in the skull, to the face and tongue. The seventh cranial nerve sends information between the brain and the muscles used in facial expression (such as smiling and frowning), some muscles in the jaw, and the muscles of a small bone in the middle ear.

Where does the auditory nerve originate?

The fibers of the cochlear nerve originate from an aggregation of nerve cell bodies in the spiral ganglion, located in the modiolus of the cochlea. The neurons of the spiral ganglion are the first of 4 order neurons between the cochlea and the cerebrum.

Is the auditory nerve part of the central nervous system?

The central auditory nervous system (CANS) includes nerve fibers and nuclei (cell bodies) of the brain stem, midbrain, and cortex. The auditory pathways in the brain stem are shown in Figure 3.

Is auditory nerve sensory or motor?

Table of cranial nerves

No. Name Sensory, motor, or both
V Trigeminal Both sensory and motor
VI Abducens Mainly motor
VII Facial Both sensory and motor
VIII Vestibulocochlear In older texts: auditory, acoustic. Mostly sensory

Where does the auditory nerve enter the brainstem?

The longer central processes of the bipolar cochlear neurons unite and are twisted like the cords of a rope to form the cochlear nerve trunk. These primary auditory fibres exit the modiolus through the internal meatus, or passageway, and immediately enter the part of the brainstem called the medulla oblongata.

Where does the auditory nerve end?

The auditory nerve terminates in the cochlear nucleus complex at the junction of the medulla and pons (Figure 2).

What are the two branches of the auditory nerve?

The auditory nerve or eighth cranial nerve is composed of two branches, the cochlear nerve that transmits auditory information away from the cochlea, and the vestibular nerve that carries vestibular information away from the semicircular canals. Each cochlear nerve contains approximately 50,000 afferent axons.

What is the primary auditory cortex?

The primary auditory cortex (A1) is located on the superior temporal gyrus in the temporal lobe and receives point-to-point input from the ventral division of the medial geniculate complex, thus, it contains a precise tonotopic map.

What are the cell bodies of auditory nerve fibers called?

Auditory Nerve

Their cell bodies, also known asspiral ganglion cells, are located in the Rosenthal canal. Humans have approximately 30,000 spiral ganglion cells,43 which are of two types:type I spiral ganglion cells are myelinated and account for approximately 90% of all spiral ganglion cells.

What nerve affects balance?

The vestibulocochlear nerve sends balance and head position information from the inner ear (see left box) to the brain. When the nerve becomes swollen (right box), the brain can’t interpret the information correctly. This results in a person experiencing such symptoms as dizziness and vertigo.

What is the auditory canal in the ear?

external auditory canal, also called external auditory meatus, or external acoustic meatus, passageway that leads from the outside of the head to the tympanic membrane, or eardrum membrane, of each ear. The structure of the external auditory canal is the same in all mammals.

What happens when the auditory nerve is damaged?

When the auditory nerve is damaged, the primary symptoms are sensorineural deafness and/or vertigo. The auditory nerve is the 8th cranial nerve. It connects the inner ear to the brain. The auditory nerve divides into two branches: the cochlear nerve and the vestibular nerve.

Which nerve connects nose to the brain?

The Anatomy of the Olfactory Nerve

Actually a pair of cranial nerves, the olfactory nerve transmits information to the brain from smell receptors in the nose. The olfactory nerve is sometimes referred to as the first cranial nerve, or CN1.

What is the 8th nerve?

The vestibulocochlear nerve, also known as cranial nerve eight (CN VIII), consists of the vestibular and cochlear nerves. Each nerve has distinct nuclei within the brainstem.

What is the 5th cranial nerve?

The trigeminal nerve, also called the cranial nerve V (that’s the Roman numeral five), is the fifth of 12 cranial nerves. You have two trigeminal nerves, one on each side of your body. They start in your brain and travel throughout your head.

Why is it called trigeminal nerve?

Its name (“trigeminal” = tri-, or three, and – geminus, or twin: so “three-born, triplet”) derives from each of the two nerves (one on each side of the pons) having three major branches: the ophthalmic nerve (V1), the maxillary nerve (V2), and the mandibular nerve (V3).

Do auditory nerves cross over?

Within the brainstem almost all fibres of the auditory nerve synapse on cells of the cochlear nucleus. … Once they leave the cochlear nucleus, most of the axons of the cochlear nucleus cells cross over to the opposite side (contralateral side) of the brain (Figure 27).

What is auditory nerve in psychology?

Definition of auditory nerve

: either of the eighth pair of cranial nerves connecting the inner ear with the brain and transmitting impulses concerned with hearing and balance — see ear illustration.

Where do auditory pathways cross?

A majority of auditory information is then transmitted through crossing fibers into the superior olivary complex. From there, the information ascends through the contralateral side of the brainstem and brain to the cortex (Figure 1C).

What are the two auditory pathways?

Auditory messages are conveyed to the brain via two types of pathway: the primary auditory pathway which exclusively carries messages from the cochlea, and the non-primary pathway (also called the reticular sensory pathway) which carries all types of sensory messages.

What are the 4 types of nerves?

These are the sensory nerves, motor nerves and mixed nerves.

Which cranial nerves are sensory motor or both?

Cranial nerves I, II, and VIII are pure sensory nerves. Cranial nerves III, IV, VI, XI, and XII are pure motor nerves. Cranial nerves V, VII, IX, and X are mixed sensory and motor nerves.

Is the hypoglossal nerve motor or sensory?

The hypoglossal nerve is mainly a somatic efferent (motor) nerve to innervate the tongue musculature. The nerve also contains some sympathetic postganglionic fibers from the cervical ganglia, which innervates tongue vessels and some small glands in the oral mucosa.

How many neurons are in the auditory nerve?

We found from 32,000 to 31,000 myelinated nerve fibres in the cochlear nerve of normal hearing individuals and any lower number in cases of sensory neural deafness.

What is the secondary auditory cortex?

Secondary auditory cortex (AII), which doesn’t have clear tonotopic organisation but has an important role in sound localisation and analysis of complex sounds: in particular for specific animal vocalisations and human language. It also has a role in auditory memory.

Is the auditory cortex on both hemispheres?

Located in the superior portion of the temporal lobe of each hemisphere, the auditory cortex consists of both primary (idiotypic) and secondary (unimodal homotypic) cortices. … The posterior portion of this secondary cortex in the left hemisphere constitutes Wernicke’s area.

Is auditory cortex in left or right hemisphere?

Where is the auditory cortex? A coronal section of the left hemisphere, showing the primary auditory cortex (red) as well as surrounding auditory regions (blue and purple). The auditory cortex is found in the temporal lobe. Most of it is hidden from view, buried deep within a fissure called the lateral sulcus.