Cranial nerves

Question 1

CN I - Olfactory

Answer 1

Special sensory - smell

Travels through cribiform plate of ethmoid to the olfactory bulb to olfactory tract to temporal lobe

Question 2

CN II - Optic

Answer 2

Special sensory - vision
Retina –> optic nerve –> optic chiasm –> optic tract –> optic radiations –> primary visual cortex in occipital lobe
Temporal visual fields cross at the chiasm.
Left brain receives right visual field information.

Question 3

CN III - Oculomotor

Answer 3

Motor
Raise upper eyelid
Extrinsic muscles of the eye –> superior, medial and inferior rectus; and inferior oblique muscles
Parasympathetic control of lens and pupil

Question 4

CN IV - Trochlear

Answer 4

Motor to superior oblique muscle

Travels through superior orbital fissure

Question 5

CN V - Trigeminal

Answer 5

Three branches
V1 - Opthalmic - travels through superior orbital fissure
V2 - Maxillary - travels through foramen rotundum
V3 - Mandibular - travels through foramen ovale
Chief sensory nerve of the face
Motor to muscles of mastication (from mandibular branch)

Question 6

CN VI - Abducens

Answer 6

Motor to lateral rectus muscle

Travels through superior orbital fissure

Question 7

CN VII - Facial

Answer 7

Branches - Temporal, Zygomatic, Buccal, Mandibular, Cervical, Chorda Tympani
Primary motor innervation for facial expression
Sensory to anterior tongue
Parasympathetic to lacrimal, submandibular and sublingual glands

Question 8

CN VIII - Vestibulocochlear

Answer 8

Vestibular - balance, position

Cochlear - hearing

Question 9

CN IX - Glossopharyngeal

Answer 9

Motor to stylypharnygeus muscle
Parasympathetic to parotid gland
Sensory to posterior tongue, pharynx, palatine tonsils
Visceral sensory to carotid sinus and carotid body

Question 10

CN X - Vagus

Answer 10

Only cranial nerve that extends outside the head and neck
Motor to larynx and pharynx
Primary parasympathetic nerve - goes to heart, lungs, GI
Special sensory to epiglottis taste buds

Question 11

CN XI - Accessory

Answer 11

Motor to sternocleidomastoid and trapezius muscles

Question 12

CN XII - Hypoglossal

Answer 12

Motor to intrinsic and extrinsic muscles of the tongue
Passes through hypoglossal canal
Comes out between the olive and the pyramids on the medulla

Question 13

Cranial nerve acronyms

Answer 13

Oh Oh Oh To Tickle A Female’s Vagina Gave Victor A Hard-on
1 nose (CN I = Olfactory)
2 eyes (CN II = Optic)
Some Say Marry Money But My Brother Says Big Brains Matter More

Question 14

What cranial nerves have a relation to the cavernous sinus?

Answer 14

CN VI is inside (along with internal carotid)

CN III, IV, V1 and V2 are on the sinus wall

Question 15

Which cranial nerves are only special sensory?

Answer 15

I, II and VIII

Olfactory, Optic and Vestibulocochlear

Question 16

Which cranial have a parasympathetic component?

Answer 16

III, VII, IX and X

Oculomotor, Facial, Glossopharyngeal, Vagus