Lets learn about the cranial nerves.
The cranial nerves are part of the peripheral nervous system.
They connect to the brain or brain stem and are represented by Roman numerals.
There are 12 pair of cranial nerves.
Here is a mnemonic to help you to remember the cranial nerves.
On old olympuss towering tops a fin and german viewed some astounding hops.
Here are the Roman numerals.
Here are the names�olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, auditory,
glossopharyngeal, vagus, spinal accessory and hypoglossal.
Lets begin with cranial nerve 1, the olfactory.
The olfactory nerve carries the sense of smell.
It begins in nasal cavity and moves through cribriform plate of ethmoid bone to primary
olfactory cortex.
Cranial nerve 2, the optic nerve, carries visual impulses from the eye.
It begins at the retina and moves posterior to form the optic chiasma which is a bridge
like structure that sends some fibers on the same side and other on the opposite side of
the brain.
The fibers continue as optic tracts to thalamus and occipital lobe.
The occipital lobe processes vision.
Eye muscle movement is processed by 3 cranial nerves 3, 4, and 6.
These are the oculomotor, trochlear and abducens nerves.
The Occulomotor nerve is motor to the superior rectus, medial rectus, inferior rectus, and
inferior oblique.
The Trochlear nerve is motor to the superior oblique muscle.
The Abducens nerve is motor to the lateral rectus muscle.
Cranial nerve 5 is the trigeminal nerve.
It is mixed with both sensory and motor components.
The sensory portion of the trigeminal carries sensation from face.
There are 3 divisions of the trigeminal nerve.
The opthalmic, maxillary and mandibular divisions.
Sensation of the face is carried by each division.
The Trigeminal nerve is also motor to masseter and temporalis muscles.
Cranial nerve 7 the facial nerve is a mixed nerve with both sensory and motor components.
The sensory portion of the Facial nerve carries taste from anterior 2/3 of tongue.
The motor component innervates the muscles of facial expression.
Cranial nerve 9 is the auditory or vestibulocochlear nerve.
It is primarily a sensory nerve.
It Carries impulses from the ear for hearing, static equilibrium and dynamic equilibrium.
Cranial nerve 9 the glossopharyngeal nerve is a mixed nerve.
The sensory portion carries taste from posterior 1/3 of tongue.
The glossopharyngeal nerve is also motor to muscles for swallowing
and carries motor impulses to parotid salivary gland.
Cranial nerve 10, the vagus nerve is a mixed nerve.
It carries sensory impulses from thoracic and abdominal organs, blood pressure receptors
(baroreceptors), and chemoreceptors for respiration.
It also carries taste from posterior portion of tongue and pharynx.
The motor portion carries impulses for swallowing and motor impulses to thoracic and abdominal
organs.
Cranail nerve 11, The spinal accessory nerve is a motor nerve.
It innervates 2 muscles, the sternocleidomastoid and trapezius.
Cranial nerve 12 the hypoglossal is primarily a motor nerve.
It controls the tongue.
We hope you have learned something about the cranial nerves and..see you next time.