Cranial Nerves

Question 1

CN I

Answer 1

Olfactory

Afferent: smell- nose

Test: identify familiar odors

Question 2

CN II

Answer 2

Optic

Afferent: sight- eye

Test: test visual fields

Question 3

CN III

Answer 3

Oculomotor

Efferent:

• voluntary: levator of eyelid; superior, medial, and inferior recti; inferior oblique muscle of eyeball
• autonomic: smooth muscle of eyeball

Test: upward, downward, and medial gaze; reaction to light

Question 4

CN IV

Answer 4

Trochlear

Efferent:
- voluntary: superior oblique muscle of eyeball

Test: downward and inward gaze

Question 5

CN V

Answer 5

Trigeminal

Afferent: touch,pain- skin of face, mucous membranes of nose, sinuses, mouth, anterior tongue

Efferent:
-voluntary: muscles of mastication

Test: corneal reflex, face sensation, clench teeth; push down on chin to separate jaw

Question 6

CN VI

Answer 6

Abducens

Efferent:
- voluntary: lateral rectus muscle of eyeball

Test: lateral gaze

Question 7

CN VII

Answer 7

facial

afferent: taste- anterior tongue

efferent:
- voluntary: facial muscles
- autonomic: lacrimal, submandibular, and sublingual glands

Question 8

CN VIII

Answer 8

vesibularcochlear

afferent:
- hearing: ear
- balance: ear

Test: hear watch ticking, hearing test, balance and coordination test

Question 9

CN IX

Answer 9

Glossopharyngeal

afferent:
- touch, pain: posterior tongue, pharynx
- taste: posterior tongue

efferent:

• voluntary motor: select muscles of pharynx
• autonomic: parotid gland

Test: gag reflex, ability to swallow

Question 10

CN X

Answer 10

vagus

afferent:

• touch pain: pharynx, larynx, bronchi
• taste: tongue, epiglottis

efferent:

• voluntary: muscles of palate, pharynx, and larynx
• autonomic: thoracic and abdominal viscera

Test: gag reflex, ability to swallow, say ahh

Question 11

CN XI

Answer 11

Accessory

efferent:
- voluntary: SCM and traps

Test: resisted shoulder shrug

Question 12

CN XII

Answer 12

Hypoglossal

efferent:
- voluntary: muscles of tongue

Test: tongue protrusion

Question 13

Olfactory Testing

Answer 13

• a positive test may be indicated by inability to identify familiar odors

Question 14

Optic Testing

Answer 14

• therapist asks to identify objects or read selected items from chart
• positive if inability to identify objects at a reasonable distance

Question 15

Oculomotor Testing

Answer 15

• have patient follow something with eyes as it is moved vertically, horizontally, and diagonally
• inspect eyes for ptosis
• positive is indicated by identified tracking deficit, asymmetry or ptosis

Question 16

Trochlear Testing

Answer 16

• have patient follow something with their eyes in the inferior direction
• positive is indicated by inability to depress the eyes or complaints of diplopia

Question 17

Trigeminal Testing

Answer 17

• therapist uses a cotton of safety pin to alternately touch the face
• positive sensory is impaired sensation or inability to differentiate between sharp and dull
• motor is tested by asking patient to perform mandibular protrusion, retrusion, and lateral deviation
• positive is inability to move mandible to through specific motions

Question 18

Abducens testing

Answer 18

• have patient abduct their eyes without rotating head

- positive is inability to abduct eyes

Question 19

Facial testing

Answer 19

• sensory: ask patient to distinguish sweet and salty substances placed on anterior portion of the tongue
• positive test is inability to identify salty and sweet
• motor is tested by performing manual muscle test of muscles involved in facial expression
• positive test is inability to mimic selected facial expressions

Question 20

Vestibulocochlear Testing

Answer 20

• take a ticking watch toward the patients ear, record distance from ear that patient is able to hear ticking clock
• positive- is indicted by inability to hear the ticking sound at inches or bilateral difference
• can also use weber and rinne test (tuning fork)

Question 21

glossoparyngeal testing

Answer 21

• patient touches pharynx with tongue depressor
• positive is lack of gagging or inability to feel tongue depressor
• sensory: have patient identify taste placed on posterior tongue
• positive is inability to distingush tastes, especially sour and bitter

Question 22

vagus testing

Answer 22

• patient touches pharynx with tongue depressor
• positive is lack of gagging or inability to feel tongue depressor
• if gag reflex is absent, therapist should assess soft palate and uvula

Question 23

Accessory testing

Answer 23

• test resisted shoulder shrug

Question 24

hypoglossal testing

Answer 24

• have patient protrude tongue

- positive is inability to protrude tongue or tongue deviating to one side