Unit 3: Cranial Nerves

What is CN I?

Olfactory nerve

Olfactory nerve parts

olfactory tract, olfactory bulb, olfactory nerves proper

The path of olfactory nerve is through foramina of the ______ _____ to reach the ____ ______.

cribriform plate, nasal cavity

Olfactory nerve type of innervation

special sensory: smell

Olfactory nerve structures innervated

olfactory epithelium

What is CN II?

optic nerve

Optic nerve parts

optic tract, optic chiasm, optic nerve

The optic nerve exits through the _____ _____ to reach the ____.

optic canal, orbit

Optic nerve type of innervation

special sensory: vision

Optic nerve structures innervated

retina

What is CN III?

oculomotor nerve

Oculomotor nerve parts

oculomotor nerve

Oculomotor nerve exits through the ______ ____ _______ to enter the ____.

superior orbital fissure, orbit

Oculomotor nerve types of innervation

somatic motor, parasympathetic

Oculomotor structures innervated for somatic motor only

superior, medial, inferior rectus, inferior oblique, levator palpebrae superioris

Oculomotor structures innervated for parasympathetic only

sphincter pupillae, ciliary muscle

What is CN IV?

trochlear nerve

Trochlear nerve parts

trochlear nerve

Trochlear nerve exits ______ ______ _____ to enter the _____.

superior orbital fissure, orbit

Trochlear nerve types of innervation

somatic motor

Trochlear nerve structures innervated

superior oblique muscle

What is CN V?

trigeminal nerve

Parts of trigeminal nerve

Ophthalmic (V1)

Maxillary (V2)

Mandibular (V3)

Parts of V1 ophthalmic nerve (of trigeminal nerve)

supraorbital nerve

Ophthalmic exits the _____ _____ _____ to enter _____

superior orbital fissure, orbit

The supraorbital nerve (of ophthalmic) exits _______ _____ from the orbit to enter the _______.

supraorbital notch, forehead

Ophthalmic type of innervation

somatic sensory

Ophthalmic structures innervated

surface of eye, skin of forehead, upper eyelid, midline of nose

Parts of V2 maxillary nerve (of trigeminal nerve)

infraorbital nerve

Maxillary nerve enters the ______ ____ via the _____ _______

pterygopalatine fossa, foramen rotundum

The infraorbital nerve (continuation of the maxillary nerve) enters the orbit through the ______ _______ _______, travels in the ______ _______ of the _______, and exits the ______ _______.

inferior orbital fissure, infraorbital groove, maxilla, infraorbital foramen

Infraorbital nerve type of innervation

somatic sensory

Infraorbital nerve structures innervated

skin of lower eyelid, upper cheek, upper lip, lateral nose, skin on side of head

Parts of V3 mandibular nerve (of trigeminal nerve)

lingual, inferior alveolar, mental

The mandibular nerve (of trigeminal) enters the _____ ______ via ____ ______

infratemporal fossa, foramen ovale

The lingual nerve is a branch of the mandibular nerve (V3) that travels to the ________ ________.

oral cavity

The inferior alveolar nerve leaves the infratemporal fossa through the ________ ________ and emerges onto the face through the ________ ________ as the ________ nerve.

mandibular foramen; mental foramen; mental

The mental nerve is the terminal branch of the ________ ________ nerve that exits the ________ ________.

inferior alveolar; mental foramen

Mandibular nerve (V3) type of innervation

Somatic sensory and somatic motor

Mandibular nerve (V3) structures innervated for somatic sensory only

Lower lip, chin, anterior 2/3 of tongue (general sensation), part of ear

Mandibular nerve (V3) structures innervated for somatic motor only

Muscles of mastication, mylohyoid, anterior belly of digastric

What is CN VI?

abducens

Parts of abducens

abducens nerve

Abducens exits via the ______ _____ ______ to enter the ____.

superior orbital fissure, orbit

Abducens type of innervation

somatic motor

Abducens structures innervated

lateral rectus muscle

What is CN VII?

Facial nerve

Facial nerve enters the temporal bone via the ____ _____ ____, and exits the temporal bone via the _______ ______.

internal auditory meatus, stylomastoid foramen

Where does the facial nerve divide?

parotid gland

Facial nerve parts

temporal, zygomatic, buccal

The temporal branch of facial nerve is posterior to the _____ _____.

zygomatic arch

The zygomatic branch of facial nerve is superior to the ______ ____.

parotid duct

The buccal branch of facial nerve is inferior to the _____ ____.

parotid duct

Facial nerve type of innervation

somatic motor, parasympathetic, special sensory

Facial nerve structures innervated for somatic motor only

muscles of facial expression, posterior digastric, stylohyoid

Facial nerve structures innervated for parasympathetic only

lacrimal, submandibular, sublingual gland

Facial nerve structures innervated for special sensory only

taste: 2/3 anterior tongue

What is CN VIII?

vestibulocochlear

Parts of vestibulocochlear nerve

vestibulocochlear nerve

The vestibulocochlear nerve enters the bony ear within the temporal bone via the _____ ______ _____.

internal auditory meatus

Vestibulocochlear nerve types of innervation

special sensory

Vestibulocochlear structures innervated

hearing: cochlea

balance: semicircular canals, vestibular organs

What is CN IX?

glossopharyngeal nerve

Parts of glossopharyngeal nerve

glossopharyngeal nerve

The glossopharyngeal nerve exits skull via _____ ______; enters pharynx by running along the surface of __________ _____

jugular foramen; stylopharyngeus muscle

Glossopharyngeal nerve innervation types

somatic motor, parasympathetic, special sensory, somatic sensory

Glossopharyngeal nerve structures innervated for somatic motor only

stylopharyngeus

Glossopharyngeal nerve structures innervated for parasympathetic only

parotid gland

Glossopharyngeal nerve structures innervated for special sensory only

taste: posterior 1/3 of tongue

Glossopharyngeal nerve structures innervated for somatic sensory only

posterior 1/3 of tongue + pharynx

What is CN X?

vagus nerve

Vagus nerve parts

internal branch of superior laryngeal, recurrent laryngeal nerve

Vagus nerve exits the skull via _____ _____. From there, it enters the thorax passing anterior to subclavian arteries and runs along the esophagus to enter the abdomen. It contributes preganglionic parasympathetic axons to autonomic plexuses.

jugular foramen

The internal branch of superior laryngeal (of vagus) pierces the ____ ______ to enter the larynx.

thyrohyoid membrane

The recurrent laryngeal nerve has a right and left branch. The right loops around the ______ _____. The left loops around the _____ _____. They both ascend to larynx near the tracheoesophageal nerve.

subclavian artery, aortic arch

Vagus nerves types of innervation

somatic motor, somatic sensory, parasympathetic

Vagus nerve structures innervated somatic motor only

pharyngeal constrictor muscles and the muscles of the larynx

Vagus nerve structures innervated somatic sensory only

larynx

Vagus nerve structures innervated parasympathetic only

thoracic organs (heart, lunges, trachea) + abdominal organs (accessory digestive, digestive tract from stomach through most of transverse colon)

What is CN XI?

accessory nerve

Parts of accessory nerve

accessory nerve

The accessory nerve originates in the spinal cord and enters the cranium through the ____ _____ and exits through the ______ _____.

foramen magnum, jugular foramen

Accessory nerve types of innervation

somatic motor

Accessory nerve structures innervated

SCM, trapezius

What is CN XII?

hypoglossal nerve

Hypoglossal nerve parts

hypoglossal nerve

Hypoglossal nerve exits via the _______ _____ to travel deep to suprahyoid muscles to enter oral cavity.

hypoglossal canal

Hypoglossal nerve types of innervation

somatic motor

Hypoglossal nerve structures innervated

muscles of the tongue