Cranial Nerves

Question 1

Which nerves are located in the cerebrum?

Answer 1

1. Olfactory
2. Optic

Question 2

Which nerves are located in the midbrain?

Answer 2

3. Oculomotor
4. Trochlear

Question 3

Which nerves are located in the pons?

Answer 3

5. Trigeminal
6. Abducens
7. Facial
8. Vestibulocochlear

Question 4

Which nerves are located in the medulla?

Answer 4

9. Glossopharyngeal
10. Vagus
11. Spinal Accessory
12. Hypoglossal

Question 5

CN 1 function

Answer 5

Sensory
Smell

Question 6

Symptoms of impaired CN 1

Answer 6

Anosmia

Question 7

CN 2 function

Answer 7

Sensory
Visual acuity
Peripheral vision
Pupillary light reflex

Question 8

Symptoms of impaired CN 2

Answer 8

Blindness
Myopia
Presbyopia

Question 9

CN 3 function

Answer 9

Motor
Eyeball movement
Opens eyelids
Pupil constriction

Question 10

CN 3 controls which muscles? Muscle functions?

Answer 10

Inferior oblique: up + in
Medial rectus: in
Superior rectus: up + out
Inferior rectus: down + out

Question 11

Symptoms of impaired CN 3

Answer 11

Strabismus (lateral)
Ptosis
Pupil dilation

Question 12

CN 4 function

Answer 12

Motor
Superior oblique (eyeball down + inward)

Question 13

CN 5 function

Answer 13

Both
Face sensation
Sensation (NOT taste) to anterior tongue
Corneal reflex (afferent)
Dampens sound

Question 14

CN 6 function

Answer 14

Motor
Lateral rectus (eyeball outward)

Question 15

CN 7 function

Answer 15

Both
Face movement
Taste to anterior tongue
Corneal reflex (efferent)
Dampens sound

Question 16

CN 8 function

Answer 16

Sensory
Balance
Hearing

Question 17

CN 9 function

Answer 17

Both
Posterior tongue sensation + taste
Gag reflex (afferent)

Question 18

CN 10 function

Answer 18

Both
Uvula deviation
Gag reflex (efferent)

Question 19

CN 11 function

Answer 19

Motor
Upper traps

Question 20

CN 12 function

Answer 20

Motor
Tongue movement

Question 21

How is hearing loss assessed?

Answer 21

Rinne Test: type of hearing loss (conductive vs. sensorineural).
Weber Test: side of hearing loss.

Question 22

Rinne Test: procedure & interpretation

Answer 22

1. Tuning fork placed on mastoid bone, time how long until pt stops hearing the sound (bone conduction).
2. Repeat with tuning fork next to ear (air conduction).
   Normal: AC > BC (2x as long)
   Sensorineural: AC > BC (not 2x as long)
   Conduction: BC > AC

Question 23

Weber Test: procedure & interpretation

Answer 23

Tuning fork placed on top of head, is the volume the same in both ears or louder in one?
Normal: equal on both sides.
Sensorineural: louder in normal ear.
Conduction: louder in affected ear.
*Mnemonic = CANS

Question 24

Sign of CN 12 injury

Answer 24

Tongue deviates TOWARD side of lesion