Face

Question 1

Answer 1

Question 2

Muscles of facial expression in the lower face are controlled by the motor cortex on the […] side of the brain as the muscles.

Answer 2

Opposite

Question 3

Answer 3

Question 4

What muscle is shown?

What is its action?

What is its innervation?

Answer 4

Buccinator

Trumpeter’s muscle - purse cheeks, move bolus of food around during chewing

Facial nerve (CN 7)

Question 5

Answer 5

Question 6

Answer 6

Question 7

Answer 7

Question 8

Explain what is happening in this diagram.

Answer 8

Beginning with CN7 nuclei in brainstem - cell body sends projection (#2, petrosal nerve) to the pterygopalatine ganglion (#3) where it synapses on neurons that provide parasympathetic innervation to the lacrimal and nasal glands (#4)

Another cell body in brainstem nucleus sends projection (#5, chorda tympani) to the submandibular ganglion (#6) where it synapses on neuruons that provide parasympathetic innervation to the submandibular and sublingual glands (#7).

Another cell body in a ganglion just outside the brainstem receives input from the medulla and sends a projection to the tongue to provide taste to the anterior 2/3 of the tongue (#8).

Question 9

The facial nerve emerges through the […], then divides into five main branches as it travels through the […] (without innervating it!).The branches carry[…] innervation to the muscles of facial expression

Answer 9

stylomastoid foramen

parotid gland

somatic motor

Question 10

Answer 10

Question 11

What muscle is shown?

What is its action?

What is its innervation?

Answer 11

Lateral Pterygoid

Question 12

Answer 12

Question 13

Answer 13

Question 14

Answer 14

Question 15

Answer 15

Question 16

The facial artery anastamoses with branches of […], which is a branch of the internal carotid artery. Thus, if the ICA is occluded, blood can still reach the brain by this connection.

Answer 16

Opthalmic artery

Question 17

Answer 17

Question 18

Answer 18

Question 19

Answer 19

Question 20

Answer 20

Question 21

What nerves supply sensory innervation to the labeled areas of the face?

Answer 21

Question 22

Describe the path from the cortex to the brainstem taken by fibers of the facial nerve that control the upper parts of the face.

Answer 22

The fibers that control the upper face take a slightly different path. After travelling down to the brainstem, half of the fibers cross over to the contralateral facial nerve, and half remain on the same side and contribute to the ipsilateral facial nerve.

Question 23

What muscle is shown?

What is its action?

What is its innervation?

Answer 23

Masseter

Question 24

The right facial nerve controls all of the muscles on the […] side and the left facial nerve controls all of the muscles on the […] side of the face

Answer 24

Right

Left

Question 25

What muscle is shown?

What is its action?

What is its innervation?

Answer 25

Frontalis

Raising eyebrow/skin on forehead

Facial nerve (right frontalis receives innervation from both R and L CN 7, same is true for left frontalis as well as all upper facial muscles)

Question 26

What nerves supply sensory innervation to the labeled areas of the face?

Answer 26

3 divisions of trigeminal nerve

• 2 - opthalmic
• 3 - maxillary
• 4 - mandibular

Question 27

The facial artery gives off branches that feed what parts of the face?

Answer 27

Lips

side of nose

medial eye

Question 28

Answer 28

Question 29

An infection of the skin of the face especially on side of nose of upper lip can drain into the […] or the […].

Answer 29

External jugular vein (good b/c outside brain)

Internal cavernous sinus (bad b/c inside brain –> can lead to brain infection)

Question 30

Answer 30

Question 31

Lesions that damage the motor cortex, such as acute ischemic strokes, will result in […] facial weakness of the […] only, with preservation of the muscles of the […], due to the […].

Answer 31

contralateral

lower face

upper face on both sides

dual innervation of the upper face

Question 32

Where does the opthalmic division of the trigeminal nerve exit the skull?

Answer 32

The superior orbital fissure

Question 33

Answer 33

Question 34

The facial nerves emerge from the middle of the brainstem (the pons) and carry motor fibers to the muscles of facial expression. These fibers come from the motor cortex of […] cerebral hemispheres

Answer 34

Both

Question 35

What muscle is shown?

What is its action?

What is its innervation?

Answer 35

Obicularis oculi

Squinting/closing of the eyelids

Facial nerve

Question 36

Describe the path from the cortex to the brainstem taken by fibers of the facial nerve that control the lower parts of the face.

Answer 36

The fibers that control the lower face travel from the cortex down to the brainstem. In the brainstem, these fibers cross over to the opposite, or contralateral, facial nerve

Question 37

Answer 37

Question 38

Where does the maxillary division of the trigeminal nerve exit the skull?

Answer 38

The foramen rotundum

Question 39

What muscle is shown?

What is its action?

What is its innervation?

Answer 39

Medial Pterygoid

Question 40

Answer 40

Question 41

Answer 41

Question 42

What innervates the platysma?

What does the platysma do?

Answer 42

CN 7 (facial nerve)

Tenses the neck

Question 43

Where does the mandibular division of the trigeminal nerve exit the skull?

Answer 43

The foramen ovale

Question 44

Answer 44

Question 45

What muscle is shown?

What is its action?

What is its innervation?

Answer 45

Temporalis

Question 46

Muscles of facial expression in the upper face are controlled by the motor cortex on the […] side of the brain as the muscles.

Answer 46

Contributions from both hemispheres –> both motor cortices

Question 47

Answer 47

Question 48

Answer 48

Question 49

Answer 49

Question 50

What muscle is shown?

What is its action?

What is its innervation?

Answer 50

Obicularis Oris

Purse one’s lips, keeps mouth closed during chewing to prevent food and saliva from escaping the mouth

CN 7 (Facial nerve)