Cranial Nerves 101

Question 1

CN I

Answer 1

Olfactory Nerve

Sense of smell

Question 2

CN II

Answer 2

Optic Nerve

Ability to see

Question 3

CN III

Answer 3

Oculomotor Nerve

Ability to move and blink your eyes

Question 4

CN IV

Answer 4

Trochlear Nerve

Ability to move your eyes up and down or back and forth

Question 5

CN V

Answer 5

Trigeminal Nerve

Sensations in your face and cheeks, taste and jaw movements

Question 6

CN VI

Answer 6

Abducens Nerve
Ability to abduct your eyes

Question 7

CN VII

Answer 7

Facial Nerve

Facial expressions and sense of taste

Question 8

CN VIII

Answer 8

Vestibular Nerve

Sense of hearing and balance

Question 9

CN IX

Answer 9

Glossopharyngeal Nerve

Ability to taste and swallow

Question 10

CN X

Answer 10

Vagus Nerve

Digestion and heart rate

Question 11

CN XI

Answer 11

Accessory Nerve

Shoulder and Neck Muscle Movement

Question 12

CN XII

Answer 12

Hypoglossal Nerve

Ability to move your tongue

Question 13

how to test olfactory nerve

Answer 13

close off one nostril and close eyes, use cinnamon/coffee and ask pt to tell you what/if they smell. test bilaterally.

Question 14

how to test optic nerve - central vision

Answer 14

have pt stand 20ft from Snellen chart and read from top until error

Question 15

how to test optic nerve - peripheral vision

Answer 15

have pt look at your nose, bring fingers in from periphery and have pt indicate when they see your finger // QUADRANT TESTING can be used too

Question 16

how to test pupillary reflex and for what nerves?

Answer 16

CN II & III

flash a flashlight into one eye at a time and look for symmetry in pupil constriction

Question 17

how to test extraoccular movement and for what nerves?

Answer 17

CN III, IV, and VI

smooth pursuit, saccades, “H” test

Question 18

how to test oculomotor nerve

Answer 18

test eye movements with smooth pursuits

Question 19

how to test trochlear nerve

Answer 19

smooth pursuits, “H” tests

Question 20

how to test abducens nerve

Answer 20

test eye movements – abduct eye

Question 21

how to test trigeminal nerve

Answer 21

pain, light touch in 3 locations: forehead, cheeks, jaw.

corneal reflex (sketchy brushing light q-tip feather on eye and pt has to blink for normal response)

palpate masseter muscles / clench teeth

Question 22

how to test facial nerve

Answer 22

facial expressions: raise eyebrows, frown, show teeth, smile, clench eyes shut, puff out cheeks

taste to anterior 2/3 tongue = apply saline/sugar solution to tongue

Question 23

how to test vestibulochochlear nerve - vestibular function

Answer 23

test balance / head-eye coordination: VOR

Question 24

how to test vestibulochochlear nerve - cochlear function

Answer 24

• Lateralization (WEBER) = place vibrating tuning fork on top of head, hear sound symmetrically
  RHINE test = place vibrating tuning fork on mastoid process

Question 25

how to test glossopharyngeal nerve

Answer 25

• sensory to posterior 1/3 of tongue - saline/sugar solution
• sensory to pharynx, middle ear = not typically tested
• phonation = listen to voice quality
• swallowing = watch them swallow
• pharynx control = say “ah”
• gag reflex = stimulate back of throat both sides

Question 26

how to test vagus nerve

Answer 26

• phonation = listen to voice quality
• swallowing = watch them swallow
• pharynx control = say “ah”
• gag reflex = stimulate back of throat both sides

Question 27

how to test accessory nerve

Answer 27

• traps = shrug both shoulders against resistance
• SCM = turn head each side against resistance

Question 28

how to test hypoglossal nerve

Answer 28

tongue movements

listen to pt’s articulation, examine resting position, ask them to stick out tongue and move it side to side