Exam 2 week 6 ppt 5 CN 9-12 Flashcards
what is the number for the Glossopharyngeal Nerve?
IX
What functional types does the glossopharyngeal nerve contain?
- –General sensory –
- tactile sensation from the tonsils, the pharynx, the middle ear and the posterior 1/3 of the tongue
- –Special sensory –
- taste from the posterior one-third of the tongue
- –Visceral sensory -
- fibers from the carotid bodies, carotid sinus
- –Somatic (Branchial motor)-
- innervates stylopharyngeus muscle
- –Visceral motor –
- parasympathetic innervation of the parotid gland (preganglionic to otic ganglion)
Glossopharyngeal nerve (IX): What is the general sensory function?
–General sensory –
tactile sensation from the tonsils, the pharynx, the middle ear and the posterior 1/3 of the tongue
Glossopharangeal Nerve (IX): what is the purpose of the special sensory component?
–Special sensory – taste from the posterior one-third of the tongue
What is the purpose of the visceral sensory component of the glossopharyngeal nerve (IX)?
–Visceral sensory - fibers from the carotid bodies, carotid sinus
What is the purpose of the Somatic (Branchial motor) component of the glossopharyngeal nerve (IX)?
–Somatic (Branchial motor)- innervates stylopharyngeus muscle
what is the stylopharyngeus muscle?
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).
What is the purpose of the visceral motor component of the glossopharyngeal nerve (IX)?
–Visceral motor – parasympathetic innervation of the parotid gland (preganglionic to otic ganglion)
where are the nuclei that serve the glossopharyngeal nerve?
Rostral Medulla
what nuclei serve the Glossopharyngeal Nerve (IX)?
- –Nucleus ambiguus –
- somatic motor
- –Inferior salivatory nucleus –
- parasympathetic preganglionics
- –Solitary nucleus –
- afferent fibers from carotid bodies & sinus
- Gustatory division of solitary nucleus serves taste from posterior 1/3 of tongue
- –Spinal trigeminal nucleus –
- sensation from tonsils, pharynx, middle ear & posterior 1/3 of the tongue
Glossopharyngeal nerve: what type of neurons does the nucleus ambigous have?
somatic motor: lower motor neurons which innervates the stylopharyngeus muscle
Glossopharyngeal nerve: what type of neurons does the Inferior salivatory nucleus have?
parasympathetic preganglionic neurons which end in the otic ganglion
Glossopharyngeal nerve: what type of neurons does the solitary nucleus have?
- afferent fibers from carotid bodies & carotid sinus whose cell bodies are in the inferior ganglion
- 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
Glossopharyngeal nerve: what type of neurons does the spinal trigeminal nucleus nucleus have?
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
What are the ganglia associated with the Glossopharyngeal nerve (IX)?
- –Superior ganglion –
- somatic afferents (cell bodies of somatic primary afferent fibers)
- –Inferior ganglion –
- visceral & special sensory (cell bodies of the visceral & special sensory primary afferent fibers)
- –Otic ganglion –
- parasympathetic efferents (the parasympathetic relay ganglion for the autonomic innervation of the parotid gland)
Glossopharyngeal nerve (IX): superior ganglion contains what kind of cell bodies?
–Superior ganglion –
somatic afferents (cell bodies of somatic primary afferent fibers)
Glossopharyngeal nerve (IX): Inferior ganglion contains what kind of cell bodies?
–Inferior ganglion –
visceral & special sensory (cell bodies of the visceral & special sensory primary afferent fibers)
Glossopharyngeal nerve (IX): otic ganglion contains what kind of cell bodies?
–Otic ganglion –
parasympathetic efferents (the parasympathetic relay ganglion for the autonomic innervation of the parotid gland)
What foramen does the glossopharyngeal nerve pass through in the cranium?
The Glossopharyngeal nerve passes out of the cranium through the jugular foramen
(the superior and inferoir ganglia are also in the jugular foramen)
Glossopharyngeal nerve: where are the superior and inferior ganglia found?
the jugular foramen
Glossopharyngeal nerve: where are the otic ganglion found?
suspended from mandibular nerve immediately below foramen ovale
what is used as a sign of function for the clinical evaluation of the glossopharyngeal nerve?
- 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.
cranial nerve number of the vagus nerve
X
list the types of functions carried in the vagus nerve:
- –General sensory
- –Special sensory
- –Branchial motor
- –Visceral motor
- –Visceral sensory (left off this diagram)
(the same 5 functions as the glossopharyngeal nerve)
list the functions of the general sensory portion of the Vagus Nerve: (5)
- –tactile sensations of the external ear
- –Pharynx & larynx
- –Cranial dura
- –Trachea & esophagus
- –Thoracic & abdominal viscera (from the viscera probably only pressure & pain)
list the functions of the special sensory portion of the Vagus Nerve:
Special sensory functions include taste from taste receptors on the Epiglottis
list the functions of the branchial motor portion of the Vagus Nerve: (7)
Somatic motor (branchial) functions of the vagus nerve includes innervation of various pharyngeal and laryngeal muscles such as the following:
- –Pharyngeal constrictors
- –Cricothyroid
- –Instrinsic laryngeal muscles
- –Levator veli palatini
- –Palatopharyngeus
- –Palatoglossus
- –Musculus uvulae
list the functions of the visceral motor portion of the Vagus Nerve:
Visceral motor includes the
- parasympathetic innervation of the organs of the Thoracic & abdominal viscera
list the functions of the visceral sensory portion of the Vagus Nerve:
Visceral sensory function includes afferents from
- atrial low pressure baroreceptors
- aortic high pressure baroreceptors
Whare are the nuclei that serve the vagus nerve located?
the medulla
list the nuclei that serve the vagus nerve (4)
- –Nucleus solitarius –
- visceral sensory afferents
- epiglottic taste - gustatory portion
- –Dorsal motor nucleus of X –
- visceral motor preganglionic parasympathetic efferents
- –Spinal Nucleus of V –
- somatic sensory (somatosensory afferents)
- –Nucleus ambiguus –
- branchial motor to the pharyngeal and laryngeal musculature
Vagus Nerve: function of nucleus soitarius
–Nucleus solitarius –
visceral sensory afferents
Vagus Nerve: function of the dorsal motor nucleus of X
–Dorsal motor nucleus of X –
visceral motor preganglionic parasympathetic efferents
Vagus Nerve: function of the Spinal Nucleus of V
–Spinal Nucleus of V –
somatic sensory (somatosensory afferents)
Vagus Nerve: function of the gustatory portion of the nucleus solitarius
–Gustatory portion of nucleus solitarius –
epiglottic taste
Vagus Nerve: function of the nucleus ambiguus
–Nucleus ambiguus –
branchial motor to the pharyngeal and laryngeal musculature
list the preipheral ganglia utilized by the vagus nerve:
- Superior ganglion – somatic afferents
- Inferior ganglion – visceral & special sensory afferents
- Terminal ganglia close to target tissues which are innervated by the vagus nerve are the parasympathetic efferents relay ganglia
Vagus Nerve: function of the superior ganglion
- Superior ganglion –
- somatic afferents
Vagus Nerve: function of the inferior ganglion
Inferior ganglion –
- visceral & special sensory afferents
Vagus Nerve: function of the terminal ganglia
Terminal ganglia close to target tissues
- innervated by the vagus nerve are the parasympathetic efferents relay ganglia
Where does the vagus nerve exit the cranium?
the jugular foramen
Vagus nerve: where are the superior and Inferior ganglia found?
jugular foramen
How can you clinically evaluate the vagus nerve? (3)
- 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
- •Observation of vocal quality
- –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)
- •Difficulty with swallowing (dysphagia)
*
meaning of dysarthria
hoarseness of speech
aphonia
inabillity to give voice
inspiratory stridor means
high pitched sound during inspiration
meaning of dysphagia
Difficulty with swallowing
number for Accessory Nerve
XI
name the functional types contained in the accessory nerve
somatic (branchial) motor
where are the nuclei that serve the Accesory Nerve located?
- 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
How does the accessory nerve cross in/out of cranium?
The Cervical ventral roots rise through the foramen magnum to join with the cranial portion.
Together both portions exits thru jugular foramen
definition of branchial
Medical Definition of BRANCHIAL. : of or relating to the gills or to parts of the body derived from the embryonic branchial arches and clefts.
Accessory Nerve Brahcnial motor innervates which muscles?
and which portions?
- –Sternocleidomastoid and upper trapezius muscles (cervical component)
- –Pharyngeal constrictors & laryngeal muscles (cranial component)
- with the vagus nerve
What can cause lesions of the accessory nerve?
•Lesions can occur with surgical procedures of the neck and with trauma
how can you clinically evaluate the integrity of the accessory nerve?
its integrity is tested using manual muscle testing against resisted
- head turning and
- shoulders shrugging
what is the CN number of the hypoglossal nerve?
XII
What types of functions does the hypglossal nerve contain?
Purely somatic motor
- innervates the intrinsic & extrinsic toung muscles
What does the hypglossal nerve innervate?
the intrinsic & extrinsic tongue muscles
where are the nuclei that serve the hypoglossal nerve located?
nuclei in the dorsal medulla
where does the hypglossal nerve exit the cranium?
The hypoglossal nerve exits thru hypoglossal canal
How can the hypoglossal nerve be clinically evaluated? (3)
- •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
