Week 8: Cranial Nerves

Question 1

Cranial Nerve #1 Olfactory Nerve

Answer 1

• Conducts information to the olfactory bub to interpret smell
• Is often damaged by a traumatic brain injury

Question 2

Cranial Nerve #2 Optic Nerve

Answer 2

Conveys visual information
- Pupillary accommodation reflex

Question 3

Cranial Nerve #3 Oculomotor Nerve

Answer 3

Innervates muscles that move the eye, open the eyelid, constrict the pupil, and modulate the curvature of the lens in the eye
- Vestibulo-ocular reflex
- Pupillary and accommodation reflexes

Question 4

Cranial Nerve #4 Trochlear Nerve

Answer 4

Innervates one muscle: the superior oblique muscle
- Vestibulo-ocular reflex

Question 5

Cranial Nerve #5 Trigeminal Nerve

Answer 5

Sensory and motor
- 3 branches: mandibular, maxillary, and opthalmic
- Responsible for chewing and adjusting the tension of the eardrum in response to loud noises
- Corneal reflex

Question 6

Cranial Nerve #6 Abducens Nerve

Answer 6

Innervates one muscle: The lateral rectus muscle
- Vestibulo-ocular reflex

Question 7

Cranial Nerve #7 Facial Nerve

Answer 7

Sensory, motor, and parasympathetic
- Corneal reflex
- Controls facial expressions
- Sensory innervation of the anterior two-thirds of the tounge

Question 8

Cranial Nerve #8 Vestibulocochlear

Answer 8

Hearing
- Balance, spatial sensation, and posture
- Vestibulo-ocular reflex

Question 9

Cranial Nerve #9 Glossopharyngeal Nerve

Answer 9

Motor control of pharynx and larynx to allow for swallowing
- Gag and swallowing reflexes
- Sensation of posterior third of the tongue

Question 10

Cranial Nerve #10 Vagus Nerve

Answer 10

Motor, sensory, parasympathetic autonomic nerve
- Sensory information from the pahrynx, larynx, and some of the external ear
- Innervates muscles of the pharynx and larynx
- Many functions of the throat, organs
Can lower hear rate, constrict bronchi, and effect speech and digestion

Question 11

Cranial Nerve #11 Spinal Accessory Nerve

Answer 11

• Innervates the trapezius and sternoclidomastoid muscles
• Controls some neck movements

Question 12

Cranial Nerve #12 Hypoglossal Nerve

Answer 12

Innervates muscles of the tongue

Question 13

Cranial nerve

Answer 13

Specialized nerves originating in the brain stem which provide afferent and efferent innervation to the head and neck

Question 14

Intorsion

Answer 14

Superior aspect of the eye twists medially

Question 15

Extorsion

Answer 15

Superior aspect of the eye twists laterally

Question 16

Pupillary Reflex

Answer 16

Autonomic adjustment of the size of the pupil based upon the amount of light that reaches the retina (CN 2 and 3)

Question 17

Vestibulo-Ocular Reflex

Answer 17

Stabilization of gaze during head movement (CN 3, 4, 6, 8)

Question 18

Congugate eye movement

Answer 18

Eyes moving in the same directions (also called conjunctive)

Question 19

Disconjugate eye movement

Answer 19

Each eye moving in a different direction (also called disjunctive)

Question 20

Accommodation Reflex

Answer 20

Modulation of vergence/convergence, lens shape and pupil size in response to looking quickly at near then far objects (or vice versa) (CN 2, 3)

Question 21

Corneal Reflex

Answer 21

Also known as the blink reflex, in response to a real or perceived external stimulus (CN 5, 7)

Question 22

Gag Reflex

Answer 22

Attempted elimination of unwanted objects from the oral cavity through muscle contraction at the base of the tongue and the pharyngeal wall (CN 9)

Question 23

Swallowing Reflex

Answer 23

Closure of the glottis, larynx elevation, cease of respiration (CN 9)

Question 24

Pupillary constriction

Answer 24

. Place pt. in a seated position
2. Darken the room to enlarge the pt. pupils. Instruct the pt. to look straight ahead.
3. Shine a penlight directly into the pupil of the eye being screened. Note whether the pupil constricts quickly or sluggishly.
4. Repeat the procedure for the other eye
5. Shine the light into both eyes at the same time so the same amount of light reaches both eyes
Oculomotor damage

Question 25

Consensual light reflex

Answer 25

1. Place the pt. in a seated position 2. Darken the room 3. Place 1 hand on the pt. nose between the eyes straight vertically 4. Shine a penlight into 1 eye and observe the pupillary reflex in the other eyes (both eyes should constrict) 5. Document whether the pupil of the unstimulated eye constricts at the same time as the pupil of the other eyes

Question 26

Screening convergence

Answer 26

1. Place the pt. in a seated position 2. Hold a pencil in front of the pt. 3. Instruct the pt. to visually fixate on the pencil 4. Begin to move the pencil in a straight line toward the pt. nose 5. Instruct the pt. to keep looking at the pencil as it is moved closer to his or her nose 6. Observe for symmetrical medial eye movement 7. Record the distance the convergence was broken or pt. could no longer medially invert both eyes 8. Note whether the pupils constricted as both eyes converged. In normally functioning eyes, the pupils constrict as they converge. Convergence is normally broken at approximately 3-4 inches from the pt. nose

Question 27

Screening the functions of the eye muscles

Answer 27

1. Screen 1 eye at a time 2. Occlude the eye not being screened 3. Instruct the pt. to maintain his or her head in a fixed position while visually scanning a moving stimulus 4. Move the visual stimulus in the shape of an H and an X allowing you to determine whether the eye-ball muscles are functioning adequately - Oculomotor moves up downward and laterally - Trochlear moves downward and laterally - Abducens moves laterally 5. Each time, note the smoothness of the movement and the distance the eye moves as it follows the visual stimulus. Document any abnormality in the smoothness or distance of movement 6. Repeat using both eyes

Question 28

Screening of the motor half of the trigeminal nerve

Answer 28

1. Place the pt. in a seated position 2. Occlude vision 3. Ask the pt. to open his or her mouth. Check for deviation of the jaw to the involved side 4. Check for asymmetry of the size of the mouth opening. If the trigeminal nerve is impaired the pt. will likely exhibit a decreased ability to open the mouth on the involved side 5. Ask the pt. to move his or her jaw from side to side. Check for asymmetry of jaw movements

Question 29

Motor portion of the facial nerve

Answer 29

1. Sit facing the pt., who is also seated 2. Ask the pt. to elevate his or her eyebrows and forehead 3. Ask the pt. to smile, frown, and pucker the lips 4. Check for asymmetry on the right and left sides of the face 5. Ask the pt. to blow his or her cheeks up with air. Gently push on the pt. cheeks while asking him or her to resist 6. Check for asymmetry of facial muscle strength

Question 30

Bell's Palsy is caused by impairment to which cranial nerve?

Answer 30

Facial Nerve #7

Question 31

The vagus nerve (CN #10) makes significant contributions to the _____ nervous system

Answer 31

Parasympathetic

Question 32

Which two cranial nerves provide sensation to the tongue

Answer 32

Facial (CN #7) & Glossopharyngeal (CN #9)

Question 33

____ is crucial for stabilization of gaze during head movement

Answer 33

Vestibulo-ocular reflex

Question 34

How Many cranial nerves are involved with the movement of the eyeball (i.e., not reflexes or vision itself)?

Answer 34

3 - Oculomotor, trochlear, and abducens

Question 35

Match the cranial nerve to how it is assessed

Answer 35

Olfactory - Client is presented with scents Optic - Client is given a visual acuity (eye chart) test Trigeminal - OT assesses light touch, hot/cold, and sharp/dull, on client's face Accessory - OT places fingers over the client's adams apple to check to rise and fall of the larynx

Question 36

An OT student on fieldwork sees their fieldwork instructor shining a pen light into the clients eyes while they look straight ahead

Answer 36

Pupillary Constriction

Question 37

An OTR screens the function of the eye muscles. During the assessment, the OTR notes the client has difficulty moving the eye up and medially. Which of the following cranial nerves are most likely impaired?

Answer 37

Oculomotor

Question 38

An OTR in acute care enters a clients room. While conversing with the client, the OTR notes asymmetry on the left side of the face during expressions like smiling. Which of the following facial nerves is most likely impaired?

Answer 38

Cranial nerve #7 facial nerve

Question 39

During the chart review, the OTR notes that the client has an impairment to cranial nerves 9 and 10. Which of the following daily living activities is the client most likely to have difficulty doing?

Answer 39

Safely eating and swallowing