Cranial Nerves

Question 1

CN I - Olfactory Nerves

Answer 1

Function: Sensory- smell (SSA)
Innervation: Olfactory epithellum
Cranial Exit: cribriform plate of ethmoid

Question 2

CN II – Optic Nerves

Answer 2

Funtion: Sensory - Visison
Innervation: Retina of the eye (very light sensitive)
Cranial exit: Optic formen of sphenoid

Question 3

CN III – Oculomotor Nerves

Answer 3

Function: Motor- eye movements; constriction of pupils
Innervation: -Levator palpebrae superioris
-Eye muscles except superior oblique (CN IV) and lateral rectus (CN VI)
Cranial Exit: Superior orbital fissure of sphenoid

Question 4

CN IV – Trochlear Nerves

Answer 4

Function: Motor - eye movements
Innervation: Superior oblique muscle of the eye (only)
Cranial exit: Superior orbital fissure of sphenoid

Question 5

CN V1 – Trigeminal Nerves: Opthalmic

Answer 5

Funtion: Sensory (Geneal Sensory)
Innervation: Orbital structures, nasal cavity, skin of forehead, eyebrows, upper eyelid, and part of nose
Cranial exit: Superior orbital fissure of sphenoid

Question 6

CN V2 Trigeminal Nerves: Maxillary

Answer 6

Function: Sensory (General sensory)
Innervation: lower eyelid, upper lip, gums, teeth, cheek, nose, palate, and pharnx
Cranial exit: Faramen rotundum

Question 7

CN V3 Trigeminal Nerves- Mandibular

Answer 7

Function: both (general sensory)
Innervation: Sensory: lower gums, teeth, lips, tongue
Motor: muscles of mastication
Cranial exit: Foramen ovale

Question 8

CN VI Abducens Nerves

Answer 8

Function: motor- eye movement
Innervation: lateral rectus muscle
Cranial exit: Superior orbital fissure of sphenoid

Question 9

CN VII – Facial Nerves

Answer 9

Functino: both (Visceral Special Afferent Sensory)
Innervation: Sensory: to taste receptors on anterior 2/3 of tongue
Motor: Muscles of facial expression, submandibular salivary gland, sublingual salivary gland, lacrimal gland
Cranial Exit: Into internal auditory meatus
Out of the stylomastoid foramen
Both temporal bone

Question 10

CN VIII Vestibulocochlear Nerves (Acoustic or Auditory)

Answer 10

Function: Sensory- hearing and balance
Innervation: Cochlear (hearing receptors) Vestibular (receptors for motion and balance)
Cranial exit: Internal auditory meatus of temporal bone

Question 11

CN IX Glossopharyngeal nerves

Answer 11

Function: both
Innervation: Sensory: Posterior 1/3 of tongue (general and special), pharynx, palate, carotid body (blood O2 levels), carotid sinus (blood pressure)
Motor: Stylopharyngeus and parotid salivary gland
Cranial exit: Jugular foramen (articulation of occipital and temporal bone)

Question 12

CN X Vagus Nerves

Answer 12

Funtion: Both
Innervation: Sensory: pharynx, tongue (very posterior), thoracic and abdominal viscera
Motor: palatal and pharyngeal muscles, laryngeal muscles, abdominal and thoracic viscera
Cranial exit: none

Question 13

CN XI spinal Accessory Nerves

Answer 13

Funtion: Motor
Innervation: Sternocleidomastoid and trapezius
Cranial Exit: Jugular foramen
There is a carnival part that immediately joins Vagus nerve

Question 14

CN XII Hypoglossal nerves

Answer 14

Funtion: Motor
Innervation: Tongue Muscles
Cranial exit: Hypoglossal canal