Exam 2 week 6 ppt 5 CN 9-12

Question 1

what is the number for the Glossopharyngeal Nerve?

Answer 1

IX

Question 2

What functional types does the glossopharyngeal nerve contain?

Answer 2

1. –General sensory –
   
   • tactile sensation from the tonsils, the pharynx, the middle ear and the posterior 1/3 of the tongue
2. –Special sensory –
   
   • taste from the posterior one-third of the tongue
3. –Visceral sensory -
   
   • fibers from the carotid bodies, carotid sinus
4. –Somatic (Branchial motor)-
   
   • innervates stylopharyngeus muscle
5. –Visceral motor –
   
   • parasympathetic innervation of the parotid gland (preganglionic to otic ganglion)

Question 3

Glossopharyngeal nerve (IX): What is the general sensory function?

Answer 3

–General sensory –

tactile sensation from the tonsils, the pharynx, the middle ear and the posterior 1/3 of the tongue

Question 4

Glossopharangeal Nerve (IX): what is the purpose of the special sensory component?

Answer 4

–Special sensory – taste from the posterior one-third of the tongue

Question 5

What is the purpose of the visceral sensory component of the glossopharyngeal nerve (IX)?

Answer 5

–Visceral sensory - fibers from the carotid bodies, carotid sinus

Question 6

What is the purpose of the Somatic (Branchial motor) component of the glossopharyngeal nerve (IX)?

Answer 6

–Somatic (Branchial motor)- innervates stylopharyngeus muscle

Question 7

what is the stylopharyngeus muscle?

Answer 7

stylopharyngeus muscle (anatomy)

On each side of the neck, stylopharyngeus is one of the internal muscles of the pharynx. It arises from the styloid process of the temporal bone. It passes inferiorly between the internal and external carotid arteries. It then enters the pharyngeal wall between the superior and middle constrictors. It inserts into the posterior and lateral border of the thyroid cartilage.

Its actions are multiple:

elevate the larynx
elevate the pharynx
dilate the pharynx to permit the passage of a large food bolus, so facilitating swallowing

Stylopharyngeus is innervated by the muscular branch of the glossopharyngeal nerve (IX).

Question 8

What is the purpose of the visceral motor component of the glossopharyngeal nerve (IX)?

Answer 8

–Visceral motor – parasympathetic innervation of the parotid gland (preganglionic to otic ganglion)

Question 9

where are the nuclei that serve the glossopharyngeal nerve?

Answer 9

Rostral Medulla

Question 10

what nuclei serve the Glossopharyngeal Nerve (IX)?

Answer 10

1. –Nucleus ambiguus –
   
   • somatic motor
2. –Inferior salivatory nucleus –
   
   • parasympathetic preganglionics
3. –Solitary nucleus –
   
   • afferent fibers from carotid bodies & sinus
   • Gustatory division of solitary nucleus serves taste from posterior 1/3 of tongue
4. –Spinal trigeminal nucleus –
   
   • sensation from tonsils, pharynx, middle ear & posterior 1/3 of the tongue

Question 11

Glossopharyngeal nerve: what type of neurons does the nucleus ambigous have?

Answer 11

somatic motor: lower motor neurons which innervates the stylopharyngeus muscle

Question 12

Glossopharyngeal nerve: what type of neurons does the Inferior salivatory nucleus have?

Answer 12

parasympathetic preganglionic neurons which end in the otic ganglion

Question 13

Glossopharyngeal nerve: what type of neurons does the solitary nucleus have?

Answer 13

1. afferent fibers from carotid bodies & carotid sinus whose cell bodies are in the inferior ganglion
2. Gustatory division of solitary nucleus – which receives taste from posterior 1/3 of tongue and again has primary afferent inputs whose cell bodies are in the inferior ganglion

Question 14

Glossopharyngeal nerve: what type of neurons does the spinal trigeminal nucleus nucleus have?

Answer 14

Spinal trigeminal nucleus – receiving somatic sensation from tonsils, pharynx, middle ear & posterior 1/3 of the tongue and again has primary afferent input but whose cell bodies are in the superior ganglion

Question 15

What are the ganglia associated with the Glossopharyngeal nerve (IX)?

Answer 15

1. –Superior ganglion –
   
   • somatic afferents (cell bodies of somatic primary afferent fibers)
2. –Inferior ganglion –
   
   • visceral & special sensory (cell bodies of the visceral & special sensory primary afferent fibers)
3. –Otic ganglion –
   
   • parasympathetic efferents (the parasympathetic relay ganglion for the autonomic innervation of the parotid gland)

Question 16

Glossopharyngeal nerve (IX): superior ganglion contains what kind of cell bodies?

Answer 16

–Superior ganglion –

somatic afferents (cell bodies of somatic primary afferent fibers)

Question 17

Glossopharyngeal nerve (IX): Inferior ganglion contains what kind of cell bodies?

Answer 17

–Inferior ganglion –

visceral & special sensory (cell bodies of the visceral & special sensory primary afferent fibers)

Question 18

Glossopharyngeal nerve (IX): otic ganglion contains what kind of cell bodies?

Answer 18

–Otic ganglion –

parasympathetic efferents (the parasympathetic relay ganglion for the autonomic innervation of the parotid gland)

Question 19

What foramen does the glossopharyngeal nerve pass through in the cranium?

Answer 19

The Glossopharyngeal nerve passes out of the cranium through the jugular foramen

(the superior and inferoir ganglia are also in the jugular foramen)

Question 20

Glossopharyngeal nerve: where are the superior and inferior ganglia found?

Answer 20

the jugular foramen

Question 21

Glossopharyngeal nerve: where are the otic ganglion found?

Answer 21

suspended from mandibular nerve immediately below foramen ovale

Question 22

what is used as a sign of function for the clinical evaluation of the glossopharyngeal nerve?

Answer 22

• The gag reflex is used as sign of function of the glossopharyngeal nerve
  
  • but this is somewhat unreliable as pharyngeal wall innervated by both glossopharyngeal and vagus nerves
  • however this is not a big problem because isolated lesions of the glossopharyngeal nerve are rare.

Question 23

cranial nerve number of the vagus nerve

Answer 23

X

Question 24

list the types of functions carried in the vagus nerve:

Answer 24

1. –General sensory
2. –Special sensory
3. –Branchial motor
4. –Visceral motor
5. –Visceral sensory (left off this diagram)

(the same 5 functions as the glossopharyngeal nerve)

Question 25

list the functions of the general sensory portion of the Vagus Nerve: (5)

Answer 25

1. –tactile sensations of the external ear
2. –Pharynx & larynx
3. –Cranial dura
4. –Trachea & esophagus
5. –Thoracic & abdominal viscera (from the viscera probably only pressure & pain)

Question 26

list the functions of the special sensory portion of the Vagus Nerve:

Answer 26

Special sensory functions include taste from taste receptors on the Epiglottis

Question 27

list the functions of the branchial motor portion of the Vagus Nerve: (7)

Answer 27

Somatic motor (branchial) functions of the vagus nerve includes innervation of various pharyngeal and laryngeal muscles such as the following:

1. –Pharyngeal constrictors
2. –Cricothyroid
3. –Instrinsic laryngeal muscles
4. –Levator veli palatini
5. –Palatopharyngeus
6. –Palatoglossus
7. –Musculus uvulae

Question 28

list the functions of the visceral motor portion of the Vagus Nerve:

Answer 28

Visceral motor includes the

1. parasympathetic innervation of the organs of the Thoracic & abdominal viscera

Question 29

list the functions of the visceral sensory portion of the Vagus Nerve:

Answer 29

Visceral sensory function includes afferents from

1. atrial low pressure baroreceptors
2. aortic high pressure baroreceptors

Question 30

Whare are the nuclei that serve the vagus nerve located?

Answer 30

the medulla

Question 31

list the nuclei that serve the vagus nerve (4)

Answer 31

1. –Nucleus solitarius –
   
   • visceral sensory afferents
   • epiglottic taste - gustatory portion
2. –Dorsal motor nucleus of X –
   
   • visceral motor preganglionic parasympathetic efferents
3. –Spinal Nucleus of V –
   
   • somatic sensory (somatosensory afferents)
4. –Nucleus ambiguus –
   
   • branchial motor to the pharyngeal and laryngeal musculature

Question 32

Vagus Nerve: function of nucleus soitarius

Answer 32

–Nucleus solitarius –

visceral sensory afferents

Question 33

Vagus Nerve: function of the dorsal motor nucleus of X

Answer 33

–Dorsal motor nucleus of X –

visceral motor preganglionic parasympathetic efferents

Question 34

Vagus Nerve: function of the Spinal Nucleus of V

Answer 34

–Spinal Nucleus of V –

somatic sensory (somatosensory afferents)

Question 35

Vagus Nerve: function of the gustatory portion of the nucleus solitarius

Answer 35

–Gustatory portion of nucleus solitarius –

epiglottic taste

Question 36

Vagus Nerve: function of the nucleus ambiguus

Answer 36

–Nucleus ambiguus –

branchial motor to the pharyngeal and laryngeal musculature

Question 37

list the preipheral ganglia utilized by the vagus nerve:

Answer 37

1. Superior ganglion – somatic afferents
2. Inferior ganglion – visceral & special sensory afferents
3. Terminal ganglia close to target tissues which are innervated by the vagus nerve are the parasympathetic efferents relay ganglia

Question 38

Vagus Nerve: function of the superior ganglion

Answer 38

• Superior ganglion –
  
  • somatic afferents

Question 39

Vagus Nerve: function of the inferior ganglion

Answer 39

Inferior ganglion –

• visceral & special sensory afferents

Question 40

Vagus Nerve: function of the terminal ganglia

Answer 40

Terminal ganglia close to target tissues

• innervated by the vagus nerve are the parasympathetic efferents relay ganglia

Question 41

Where does the vagus nerve exit the cranium?

Answer 41

the jugular foramen

Question 42

Vagus nerve: where are the superior and Inferior ganglia found?

Answer 42

jugular foramen

Question 43

How can you clinically evaluate the vagus nerve? (3)

Answer 43

1. The clinical evaluation of the vagus nerve begins with the Observation of movements of the soft palate when patient says “Ahh”.
   
   • With a vagus nerve lesion there will be a Deviation of the uvula to the unaffected side.
   • may also be a noticable Asymmetry of arch of soft palate on affected side
2. •Observation of vocal quality
   
   1. –Lesions of CN X specifically recurrent laryngeal nerve can produce hoarseness of speech (dysarthria), inability to give voice (aphonia) or inspiratory stridor (high pitched sound during inspiration)
3. •Difficulty with swallowing (dysphagia)

*

Question 44

meaning of dysarthria

Answer 44

hoarseness of speech

Question 45

aphonia

Answer 45

inabillity to give voice

Question 46

inspiratory stridor means

Answer 46

high pitched sound during inspiration

Question 47

meaning of dysphagia

Answer 47

Difficulty with swallowing

Question 48

number for Accessory Nerve

Answer 48

XI

Question 49

name the functional types contained in the accessory nerve

Answer 49

somatic (branchial) motor

Question 50

where are the nuclei that serve the Accesory Nerve located?

Answer 50

• Medulla–
  
  • Nucleus ambiguus
• Cervical Spinal Cord–
  
  • Cervical ventral horn

The cranial portion arises from the Nucleus ambiguus of the medulla and the spinal portion arises from motor neurons of the upper Cervical ventral horn. The Cervical ventral roots rise through the foramen magnum to join with the cranial portion.

Together both portions exits thru jugular foramen

Question 51

How does the accessory nerve cross in/out of cranium?

Answer 51

The Cervical ventral roots rise through the foramen magnum to join with the cranial portion.

Together both portions exits thru jugular foramen

Question 52

definition of branchial

Answer 52

Medical Definition of BRANCHIAL. : of or relating to the gills or to parts of the body derived from the embryonic branchial arches and clefts.

Question 53

Accessory Nerve Brahcnial motor innervates which muscles?

and which portions?

Answer 53

• –Sternocleidomastoid and upper trapezius muscles (cervical component)
• –Pharyngeal constrictors & laryngeal muscles (cranial component)
  
  • with the vagus nerve

Question 54

What can cause lesions of the accessory nerve?

Answer 54

•Lesions can occur with surgical procedures of the neck and with trauma

Question 55

how can you clinically evaluate the integrity of the accessory nerve?

Answer 55

its integrity is tested using manual muscle testing against resisted

• head turning and
• shoulders shrugging

Question 56

what is the CN number of the hypoglossal nerve?

Answer 56

XII

Question 57

What types of functions does the hypglossal nerve contain?

Answer 57

Purely somatic motor

• innervates the intrinsic & extrinsic toung muscles

Question 58

What does the hypglossal nerve innervate?

Answer 58

the intrinsic & extrinsic tongue muscles

Question 59

where are the nuclei that serve the hypoglossal nerve located?

Answer 59

nuclei in the dorsal medulla

Question 60

where does the hypglossal nerve exit the cranium?

Answer 60

The hypoglossal nerve exits thru hypoglossal canal

Question 61

How can the hypoglossal nerve be clinically evaluated? (3)

Answer 61

• •Observation of tongue protrusion with deviation toward affected side
• •Problems with speech articulation (dysarthria)
• •Atrophy of the tongue

Clinical examination of the hypoglossal nerve involves Observation of tongue protrusion with deviation toward affected side as seen in both the upper and lower pictures and Problems with speech articulation (dysarthria). Holding tongue “speech sounds something like this”. Also atrophy of the tongue is seen due to damage of the final common pathway to the skeletal muscle of the tongue as you can see in the lower picture