Cranial Nerves

Question 1

What are the cranial nerves?

Answer 1

I Olfactory
II Optic
III Occulomotor
IV Trochlear
V Trigeminal
VI Abducens
VII Facial
VIII Vestibulocochlear 
IX Glossopharyngeal 
X Vagus
XI Spinal Accessory
XII Hypoglossal

Question 2

Is I Olfactory motor or sensory?

Answer 2

sensory

Question 3

What does II Optic do?

Answer 3

sensory only, vision, 50% of fibers on each side decussate

Question 4

Is III Occulomotor motor or sensory?

Answer 4

Primarily motor

Question 5

What is III Occulomotor responsible for?

Answer 5

visual tracking, fixation on objects, pupil adjustments and reflexes, elevation of eyelids

Question 6

Is IV Trochlear motor or sensory?

Answer 6

motor

Question 7

What does IV Trochlear do?

Answer 7

depresses, rotates, abducts the eye

Question 8

Where does V Trigeminal originate from?

Answer 8

pons

Question 9

is V Trigeminal motor or sensory?

Answer 9

both

Question 10

What are the three branches of V Trigeminal?

Answer 10

Opthalmic (sensory) - sensation in the upper face
Maxillary (sensory) - sensation in frontal of face
Mandibular (sensory and motor) - sensation and motion in mandible

Question 11

What is VI Abducens?

Answer 11

motor only, eyes

Question 12

Where does VII Facial originate?

Answer 12

pons

Question 13

What are the major responsibilities of VII Facial?

Answer 13

speech and facial expression, taste

Question 14

How many branches are there in VII Facial?

Answer 14

tons and tons

Question 15

What are the two of the four major divisions of VII Facial that we need to know?

Answer 15

• Branchial motor - voluntary control of muscles of facial expression and the muscles of the neck
• Special sensory - taste info from anterior 2/3 of tongue hard and soft palates

Question 16

Is VIII Vestibulocochlear sensory or motor?

Answer 16

sensory only

Question 17

What are the two components of VIII?

Answer 17

vestibular and auditory branches

Question 18

Where does IX Glossopharyngeal start?

Answer 18

medulla

Question 19

Is IX Glossopharyngeal sensory or motor?

Answer 19

both

Question 20

What is the branch (out of 5) from glossopharyngeal that we need to know?

Answer 20

special sensory (taste sensation from posterior one-third of the tongue

Question 21

Where does X Vagus originate?

Answer 21

medulla

Question 22

What is the MAJOR branch of X Vagus that we need to know?

Answer 22

Branchial motor - voluntary control of pharynx, larynx, and palatoglossus muscles of the tongue

Question 23

What are the three major branches of the branchial motor branch of X Vagus?

Answer 23

Pharyngeal - taste and sensation in pharynx
Superior Laryngeal - innervates upper larynx (external and internal branches)
Recurrent Laryngeal - innervates all intrinsic laryngeal muscles except cricothyroid

Question 24

What are the two branches of the superior laryngeal branch of the branchial motor branch of X Vagus?

Answer 24

External - serves inferior constrictor muscle and cricothyroid muscle
Internal - sensory nerve for larynx

Question 25

is XI Spinal Accessory motor or sensory?

Answer 25

motor

Question 26

Where does XI Spinal Accessory originate?

Answer 26

medulla

Question 27

What are the two components of XI Spinal accessory?

Answer 27

Cranial root - motor innervation of pharynx and larynx (courses with X Vagus for this) Spinal root - head turning

Question 28

Is XII Hypoglossal motor or sensory?

Answer 28

motor

Question 29

What does XII Hypoglossal do?

Answer 29

innervates all extrinsic tongue muscles except palatoglossus

Question 30

damage to X Vagus can have implications for what?

Answer 30

speech, swallowing, voicing

Question 31

If recurrent laryngeal branch of branchial motor branch of X Vagus is damaged, what might happen?

Answer 31

vocal fold paresis