Anatomy - CN VII-XII

Question 1

All general somatic sensory fibers synapse on ___

Answer 1

Cells of the trigeminal complex

Does not matter which Cranial Nerve they are in

Question 2

All taste sensory fibers terminate in __

Answer 2

The rostrum half of the solitary nucleus

Question 3

All general visceral sensory fibers terminate in ___

Answer 3

The caudal half of the solitary nucleus

Question 4

Special sensory fibers serving audition and vestibular sense synapse on ___

Answer 4

Specific nuclei of he brainstem

Question 5

Somatic motor neurons arise from ___

Answer 5

Discrete motor nuclei

Arranged in a rostral-caudal order within the brainstem

Question 6

Preganglionic parasympathetic fibers are found in which nerves?

Answer 6

Facial n.
Glossopharyngeal n.
Vagus n.

Question 7

The preganglionic parasympathetic sonata are in ___ nuclei

Answer 7

Pontine and

Medullary

Question 8

CN VII

Answer 8

Facial n.

Muscles of facial expression

Question 9

Somatic motor neurons of CN VII are in the facial motor nucleus of the __

General pathway?

Answer 9

Pons

Axons leave CN VII and course through the temporal bone and middle ear cavity (innervates stapedius here) before exiting the base of the skull

Innervates stylohyoid and p. belly of digastric as it exits the skull

Enters parotid gland and divides into 5 branches

Question 10

CN VII is also a source of preganglionic and parasympathetic control of __

Answer 10

Glands in the head

Preganglionic cell bodies are in the superior salivatory nucleus of the medulla

Question 11

Greater petrosal n.

Answer 11

Some fibers of CN VII diverge at geniculate ganglion

They pass anteriorly across middle cranial fossa
Enters pterygopalatine fossa
Synapse in pterygopalatine ganglion

Question 12

Chorda tympani

Answer 12

Some CN VII fibers leave as it passes through the middle ear

Joins lingual n. in the infratemporal fossa

Question 13

Preganglionic fibers of chorda tympani synapse in the ___

Answer 13

Submandibular ganglion

Question 14

What do postganglionic parasympathetic fibers of chorda tympani do?

Answer 14

control secretion from submandibular and sublingual salivary glands

Question 15

What supplies visceral sensation of taste to the anterior two-thirds of the tongue?

Where are these neurons located? Where do they synapse?

Answer 15

Sensory fibers in CN VII

Located in a ganglion in the temporal bone

synapse on rostral half of solitary nucleus in the brainstem

Question 16

CN VII is also involved in somatic sensation to which three areas?

Where are these sensory cell bodies located?

Answer 16

external auditory canal
ear
a small area in the oropharynx

Located in the geniculate ganglion, synapse on cells of the trigeminal sensory complex

Question 17

CN VIII ? Receives input from? Where do central processes go?

Answer 17

Auditory/Vestibulocochlear

Receives input from auditory and vestibular apparatuses

Central processes go into brainstem

Question 18

CN IX functions

Answer 18

Glossopharyngeal

2 motor, 3 sensory

Question 19

Which CN innervates stylopharyngeus?

Answer 19

CN IX

somatic motor neurons in nucleus ambiguus

Question 20

Preganglionic parasympathetic cells in the salivatory nucleus of the medulla send axons to which CN?

Answer 20

CN IX

Question 21

Which part of the tongue does CN IX supply? What kind of innervation? What else gets this kind from this nerve?

Answer 21

Posterior tongue

General somatic sensation
-also to oropharynx and middle ear cavity

Question 22

Path of preganglionic parasympathetic fibers of CN IX

Answer 22

Diverge from CN IX at the base of the skull

Enter and pass through middle ear cavity

Exits middle ear cavity as lesser petrosal n.

Synapses on postganglionic cells in optic ganglion deep in the infratemporal fossa

Postganglionic axons join auriculotemporal n. and innervate parotid salivatory gland

Question 23

Sensory cell bodies of CN IX are located where?

for somatic sensation to posterior tongue, oropharynx, and middle ear cavity

Answer 23

Superior ganglion near the base of the skull

Question 24

Sensory cell bodies of CN IX are located where?

For taste sensation to posterior tongue

Answer 24

Inferior ganglion near the base of the skull

Question 25

Central processes end where? for somatic sensation to posterior tongue, oropharynx, and middle ear cavity

Answer 25

On the chief sensory nucleus and/or spinal nucleus of trigeminal

Question 26

Central processes synapse where? For taste to posterior tongue

Answer 26

Rostral half of solitary nucleus

Question 27

CN IX conveys general visceral sensory information concerning blood oxygen levels and blood reassure from receptors in the___ Sensory cell bodies are found __ Central processes synapse__

Answer 27

Carotid a. Sensory cell bodies are found in the inferior ganglion of IX central processes synapse on caudal half of solitary nucleus

Question 28

CN X functions

Answer 28

Vagus n. | 2 motor, 3 sensory functions

Question 29

List of CN VII functions

Answer 29

1. Somatic motor to muscles of facial expression 2. Preganglionic parasympathetic control of glands in the head 3. Visceral sensation of taste to anterior 2/3 of tongue 4. Limited somatic sensation to external auditory canal and small area of oropharynx

Question 30

List of CN IX functions

Answer 30

1. Somatic motor to stylopharyngeus 2. Parotid salivary gland 3. Limited general somatic sensation to posterior tongue, oropharynx, and middle ear cavity 4. Taste sensation to posterior 1/3 of tongue 5. Visceral sensory info about blood oxygen levels and BP from carotid a.

Question 31

List of CN X functions

Answer 31

1. Somatic motor to most of the muscles in the pharynx and larynx 2. Preganglionic parasympathetic to organs of thorax and abdomen to the level of the left colic flexure 3. General visceral afferents for functional status of thoracic and abdominal organ systems 4. General sensation and taste to small part of posterior tongue and pharyngeal wall

Question 32

CN X cell bodies for preganglionic parasympathetic organ innervation are located ___

Answer 32

Dorsal motor nucleus of X in the medulla

Question 33

Somatic motor neurons in nucleus ambiguus send axons in CN X to innervate ___

Answer 33

Most of the muscles of the pharynx and larynx

Question 34

CN X sensory cell bodies for visceral afferents that convey functional info of thorax and abdomen are located ___ Where do centralbprocesses synapse?

Answer 34

Inferior ganglion of X near the base of the skull Central processes synapse on the cells in the caudal solitary nucleus

Question 35

CN X sensory cell bodies for taste are located ___ and central processes synapse ___

Answer 35

Superior and inferior vagal ganglia Cells in the trigeminal spinal nucleus and solitary nucleus respectively

Question 36

Patients with vagal dysfunction often present with__

Answer 36

Low and soft voice Aspirating fluids or food Asymmetrical elevation of soft palate

Question 37

CN XI functions

Answer 37

Spinal Accessory n. Strictly motor to trapezius and SCM

Question 38

Somatic motor neurons of CN XI are located ___ Pathway __

Answer 38

Central horn at C1-C4 levels of the spinal cord Axons exit the lateral surface of the cervical cord Pass through foramen magnum INTO THE SKULL Axons leave the skull through jugular foramen

Question 39

CN XII function

Answer 39

Hypoglossal n. Only one function: innervates all intrinsic and extrinsic muscles of the tongue EXCEPT palatoglossus (which is by CN X)

Question 40

Pathway of CN XII

Answer 40

Axons arise from neuronal somata of the hypoglossal nucleus Exit the brainstem Pass through hypoglossal canal Pass anteriorly to enter the deep floor of the mouth

Question 41

How do you test CN VII?

Answer 41

Test contraction of superficial facial muscles from frontalis to platysma Pt could also complain of: dry eye Loss of taste to anterior 2/3 loss of eye abduction All ipsilateral

Question 42

How do you test CN IX?

Answer 42

Stimulate oropharynx to elicit gag reflex -could be false positive (facial and vagus nerves also in that area) Touch and taste to posterior tongue

Question 43

Glands that CN VII innervates

Answer 43

Lacrimal Mucous glands of nasal cavity Submandibular salivary Sublingual salivary