S3_L2: Cranial Nerves Flashcards
1
Q
Longest cranial nerve
A
Vagus nerve / CN X
2
Q
Mediates phonation, swallowing, and elevation of the palate and taste
A
Vagus nerve / CN X
3
Q
Innervates viscera of the neck, thorax, and abdomen
A
Vagus nerve / CN X
4
Q
Mediates head and shoulder movement and innervates laryngeal muscles
A
Accessory nerve / CN XI
5
Q
Mediates tongue movement and shape & innervates intrinsic and extrinsic muscles of the tongue
A
Hypoglossal nerve / CN XII
6
Q
When the twelfth cranial nerve has been transected, what is the result?
A
Hemiparalysis of the tongue
7
Q
When the tongue protrudes as a result of a lesion to the hypoglossal nerve, the tongue points toward the weak side due to unopposed action of the ___
A
opposite genioglossus muscle
8
Q
The hypoglossal nerve exits the skull via the ___
A
hypoglossal canal
9
Q
The hypoglossal nerve is a pure general somatic efferent (GSE) nerve arising from the hypoglossal nucleus of the ___.
A
medulla oblongata
10
Q
Paralysis of this muscle results in difficulty in turning the head to the side opposite the lesion
A
sternocleidomastoid muscle
11
Q
Paralysis of this muscle results in a shoulder droop and the inability to shrug the ipsilateral shoulder
A
Trapezius muscle
12
Q
Lesions of the CN XI / accessory nerve result in the paralysis of what 3 structures?
A
- Sternocleidomastoid
- Trapezius
- Larynx
13
Q
The cranial division of the accessory nerve arises from the ___ of the medulla oblongata
A
nucleus ambiguus
14
Q
The spinal division of the accessory nerve arises from the ventral horn of ___.
A
cervical segments C1-C6
15
Q
Which division of the accessory nerve innervates the sternocleidomastoid and trapezius muscles?
A
Spinal division
16
Q
Which division of the accessory nerve innervates the intrinsic muscles of the larynx via the inferior recurrent laryngeal nerve with the exception of the cricothyroid muscle?
A
Cranial division
17
Q
The accessory nerve / CN XI contains the ___ component
A
special visceral efferent (SVE)
18
Q
Predominantly a sensory nerve that mediates taste, salivation and swallowing
A
Glossopharyngeal nerve / CN IX
19
Q
Which 3 cranial nerves all exit the skull via the jugular foramen?
A
- CN IX / glossopharyngeal
- CN X / vagus
- CN XI / accessory
20
Q
Mediates facial movements, taste, salivation, and lacrimation
A
Facial nerve / CN VII
21
Q
Pure general somatic efferent (GSE) nerve that innervates the lateral rectus muscle which abducts the eye
A
Abducens nerve / CN VI
22
Q
The abducens nerve arises from the abducens nucleus of the ___.
A
Caudal pons
23
Q
Innervates muscles of mastication and mediates general sensation from the face, eye and nasal and oral cavities
A
Trigeminal nerve / CN V
24
Q
Longest intracranial nerve
A
Trochlear nerve / CN IV
25
What are the movements of the superior oblique muscle?
Depresses, intorts and abducts the eye / Turning the eyeball downward and laterally
26
Pure general somatic efferent (GSE) nerve that innervates the superior oblique muscle
Trochlear nerve / CN IV
27
The trochlear nerve arises from the ____ nucleus of the midbrain
Contralateral trochlear
28
Paralysis of this nerve results in extorsion of the eye and weakness of downward gaze, vertical diplopia, and head tilting
Trochlear nerve / CN IV
29
Which 3 cranial nerves are entirely sensory?
1. CN I / olfactory
2. CN II / optic
3. CN VIII / vestibulocochlear
30
Which 5 cranial nerves are entirely motor?
1. CN III / oculomotor
2. CN IV / trochlear
3. CN VI / abducens
4. CN XI / accessory
5. CN XII / hypoglossal
31
Which 4 cranial nerves are both sensory and motor nerves?
1. CN V / trigeminal
2. CN VII / facial
3. CN IX / glossopharyngeal
4. CN X / vagus
32
TRUE OR FALSE: The cranial nerves have central motor and/or sensory nuclei within the brain and peripheral nerve fibers that emerge from the brain and exit from the skull to reach their effector or sensory organs.
True
33
What are the special visceral afferent sensations?
Smell and taste
34
What are the special somatic afferent sensations?
Hearing, balance, vision
35
What do the general visceral efferent nerves supply?
Glands and smooth muscles (via parasympathetic innervation)
36
What do the special visceral efferent nerves supply?
Branchial arch striated muscles
37
Which 4 cranial nerves exit the skull via the superior orbital fissure?
1. Oculomotor
2. Trochlear
3. Ophthalmic division of trigeminal nerve
4. Abducens
38
Which tongue muscle is not innervated by the hypoglossal nerve?
Palatoglossus muscle
39
Enumerate the 4 cranial nerves with general visceral efferent components and their corresponding GVE nuclei
1. Oculomotor, Edinger-Westphal nucleus
2. Facial, Superior salivatory and lacrimal nuclei
3. Glossopharyngeal, Inferior salivatory nucleus
4. Vagus, dorsal motor nuclei
40
The general visceral motor nuclei form the cranial outflow of the ___ portion of the autonomic nervous system
parasympathetic
41
The maxillary division of the trigeminal nerve exits the skull via the (1)___, while the mandibular division exits via the (2)___.
1. Foramen rotundum
2. Foramen ovale
42
The only cranial nerve that projects directly to the forebrain
Olfactory / CN I
43
The olfactory nerve enters the skull via the
Cribriform plate of the ethmoid bone
44
The optic nerve enters the skull via the
Optic canal of the sphenoid bone
45
It is not a true peripheral nerve but a tract of the diencephalon
Optic nerve / CN II
46
When it is damaged, anosmia results. It may be acquired in common colds, or due to a foreign body or tumor compressing its related structures.
Olfactory nerve / CN I
47
A special sensory somatic afferent (SSA) nerve that subserves vision and pupillary light reflexes and consists of axons and neurons located in the ganglion cell layer of the retina.
Optic nerve / CN II
48
A special visceral afferent (SVA) nerve that mediates sense of smell and consists of unmyelinated axons of bipolar neurons located in the nasal mucosa, the olfactory epithelium.
Olfactory nerve / CN I
49
It projects to the ciliary ganglion of the orbit via CN III and it is the motor component of vision and the pupillary light reflex
Edinger-Westphal nucleus
50
It projects postganglionic parasympathetic fibers to the sphincter muscle of the iris (miosis) and to the ciliary muscle (accommodation).
Ciliary ganglion
51
Diabetes mellitus frequently affects the ___ nerve, damaging the central fibers and sparing the pupilloconstrictor fibers. The patient will present with pupils that are normal in function but may have doubling in vision.
oculomotor
Result: Diabetic oculomotor palsy
52
Denervation of the extraocular muscles causes the affected eye to ____
look down and out
Reason: Unopposed action of the superior oblique muscle
53
Denervation of the levator palpebrae muscle results in ___
ptosis
54
A lesion related to the ciliospinal center of Budge results in?
Ipsilateral Horner’s syndrome
55
What are the four common signs and symptoms related to Ipsilateral Horner’s syndrome?
1. Miosis (pupillary constriction)
2. Ptosis (drooping of upper eyelid)
3. Anhidrosis (loss of sweating)
4. Anisocoria (unequal pupil sizes)
56
A lesion of the vagus nerve resulting in ipsilateral paralysis of the soft palate, pharynx, and larynx leads to what four clinical manifestations?
1. Dysphonia (difficulty making sounds)
2. Dyspnea (difficulty breathing)
3. Dysarthria (difficulty speaking)
4. Dysphagia (difficulty swallowing)
57
Loss of gag reflex is a result of a lesion to what 2 cranial nerves?
1. glossopharyngeal nerve
2. vagus nerve
58
A pure special sensory afferent nerve that serves to maintain balance and mediate hearing
Vestibulocochlear / CN VIII
59
Determine the corresponding descriptions of the two functional divisions of CN VIII
1. Associated functionally with the cerebellum
2. Lesion to this results in disequilibrium, vertigo and nystagmus
3. Conducts efferent fibers to the hair cells from the brainstem
4. Lesion to this can cause tinnitus (ringing sounds)
5. Regulates compensatory eye movements
A. Vestibular nerve
B. Cochlear nerve
1. A
2. A
3. B
4. B
5. A
60
Determine the corresponding descriptions of the two functional divisions of CN VIII
1. Serves audition
2. Has its first-order sensory bipolar neurons in the vestibular ganglion of the internal auditory meatus
3. Serves equilibrium and balance
4. Lesion to this results in hearing loss (sensorineural deafness)
5. Projects its peripheral processes to the hair cells of the organ of Corti
A. Vestibular nerve
B. Cochlear nerve
1. B
2. A
3. A
4. B
5. B
61
Mediates input from the carotid sinus and carotid body
Glossopharyngeal / CN IX
62
Contains baroreceptors that monitor arterial blood pressure
Carotid sinus
63
Contains chemoreceptors that monitor the CO2 and O2 concentration of the blood
Carotid body
64
Supplies the cornea, skin of forehead, scalp, eyelids, and nose; also mucous membrane of paranasal sinuses and nasal cavity
Ophthalmic division of the trigeminal nerve
65
Supplies the skin of face over maxilla; teeth of upper jaw; mucous membrane of nose, the maxillary sinus, and palate
Maxillary division of the trigeminal nerve
66
Supplies the muscles of mastication, mylohyoid, anterior belly of digastric, tensor veli palatini, and tensor tympani
Mandibular division of the trigeminal nerve
67
A lesion to the trigeminal nerve may result in deviation of the patient’s jaw to the weak side, due to unopposed action of the ____
lateral pterygoid muscle
68
Nerve of the second pharyngeal arch (hyoid)
Facial / CN VII
69
Nerve of the third pharyngeal arch
Glossopharyngeal / CN IX
70
Nerve of the fourth and sixth branchial arches
Vagus / CN X
71
It is one of the most important organs supplied by vagus nerve
Heart
72
A lesion to the vagus nerve can result in aortic aneurysms and tumors of the neck and thorax, as well as anesthesia of the pharynx and larynx, leading to unilateral loss of the ___
cough reflex
73
Inability to abduct the eye to the unopposed action of the medial rectus muscle
Convergent strabismus (esotropia)
74
Abducens (CN VI) paralysis results in what 2 signs/symptoms?
1. Convergent strabismus (esotropia)
2. Horizontal diplopia
75
Most common isolated muscle palsy
Abducens (CN VI) paralysis
76
Nerve of the first pharyngeal arch (mandibular)
Trigeminal / CN V
77
Loss of corneal reflex is a result of a lesion to the ___
Trigeminal / CN V
78
Loss of the corneal (blink) reflex is a result of a lesion to the ___
Facial / CN VII
79
It is responsible for motor component for corneal reflex
Facial nerve
80
Loss of taste from the __ of the tongue can be a result of a lesion to the glossopharyngeal nerve
posterior third
81
Determine the corresponding descriptions of the vagus nerve components
1. Innervates the taste buds in the epiglottis
2. Provides the efferent limb of the gag reflex
3. Has cell bodies in the superior jugular ganglion
4. Innervates the viscera of the neck and of the thoracic and abdominal cavities as far as the left colic flexure
5. Innervates the mucous membranes of the pharynx, larynx, esophagus, trachea, and thoracic and abdominal viscera
A. GSA component
B. GVA component
C. SVA component
D. SVE component
E. GVE component
1. C
2. D
3. A
4. E
5. B
82
Determine the corresponding descriptions of the vagus nerve components
1. Innervates the pharyngeal arch muscles of the larynx and pharynx, striated muscle of the upper esophagus, muscle of the uvula and levator veli palatini and palatoglossus muscles
2. Innervates the infratentorial dura posterior surface of the external ear, external auditory meatus and tympanic membrane
3. Projects its central processes to the spinal trigeminal tract and nucleus
4. Arises from the nucleus ambiguus in the lateral medulla
A. GSA component
B. GVA component
C. SVA component
D. SVE component
1. D
2. A
3. A
4. D
83
Which two components of the vagus nerve have cell bodies in the inferior (nodose) ganglion and project its central processes to the solitary tract and nucleus?
1. General visceral afferent component
2. Special visceral afferent component
84
Determine the corresponding nerves affected in the following conditions/clinical manifestations
1. Loss of the carotid sinus reflex
2. Jaw drop position
3. Flaccid paralysis of the muscles of mastication
4. Loss of taste
5. Loss of general sensation from the face and mucous membranes of the oral and nasal cavities
A. Trigeminal nerve
B. Facial nerve
C. Glossopharyngeal nerve
1. C
2. A
3. B
4. A
5. A
85
Determine the corresponding descriptions of conditions caused by a lesion to the facial nerve
1. Facial nerve lesion proximal to the geniculate ganglion
2. Occurs when trying to close the eyes, affected eye looks up and out
3. Transection of corticobulbar fibers in the internal capsule and results in contralateral facial weakness below the orbit
4. Pure facial nerve paralysis
5. Increased sensation to high-pitched sounds
A. Hyperacusis
B. Bell’s palsy
C. Bell’s phenomenon
D. Central facial palsy
E. Crocodile tears syndrome
1. E
2. C
3. D
4. B
5. A
86
An upper motor neuron lesion affecting the muscles of the lower face. An example of this is when the lesion is on the (L) corticospinal tract, the contralateral lower face (R) side is affected.
Central facial palsy
87
A condition where regenerating preganglionic salivatory fibers are misdirected to the pterygopalatine ganglion which projects to the lacrimal gland. Lacrimation during eating ensues.
Crocodile tears syndrome
88
Paralysis of the tensor tympani, leading to hypoacusis (partial deafness to low-pitched sounds) is caused by a lesion to which cranial nerve?
Trigeminal / CN V
89
Laymanized term for glossopharyngeal neuralgia
Sore throat
90
Which cranial nerve has cell bodies located in the geniculate ganglion?
Facial / CN VII
91
Which cranial nerve opens into the skull via the internal acoustic meatus, facial canal, and stylomastoid foramen?
Facial / CN VII
92
Which cranial nerve opens into the skull via the internal auditory meatus?
Vestibulocochlear / CN VIII
93
Which cranial nerve exits the brainstem from the inferior pontine sulcus?
Abducens / CN VI
94
Which cranial nerves exits the brainstem in the cerebellopontine angle?
Facial & Vestibulocochlear / CN VII & CN VIII
95
Bilateral connections are present for all cranial motor nuclei except for part of the facial nucleus that supplies the muscles of the (1)___ part of the face and a part of the hypoglossal nucleus that supplies the (2)___.
1. lower
2. genioglossus muscle
96
The motor nuclei of the cranial nerves receive impulses from the cerebral cortex through the ___ fibers
Corticonuclear (corticobulbar)
97
Which cranial nerve exits the brainstem from the pons?
Trigeminal / CN V
98
Determine the corresponding actions of the muscles the oculomotor nerve innervates
1. depresses, extorts, adducts eye
2. elevates upper lid
3. adducts eye
4. elevates, intorts, adducts eye
5. elevates, extorts, abducts eye
A. Medial rectus
B. Superior rectus
C. Inferior rectus
D. Inferior oblique
E. Levator palpebrae
1. C
2. E
3. A
4. B
5. D
99
Innervates the dura of the anterior and middle cranial fossae. Dysfunction to this would cause a toothache.
General somatic afferent component of trigeminal / CN V
100
Innervates the taste buds from the anterior two-thirds of the tongue via the intermediate nerve, chorda tympani, and lingual nerve (branch of CN V3).
Facial / CN VII
101
Characterized by the interruption of parasympathetic innervation which results in a dilated and fixed pupil and paralysis of accommodation (cycloplegia). Results in diplopia when the patient looks in the direction of the paretic muscle.
Oculomotor paralysis
Additional: Seen in transtentorial herniation (subdural or epidural hematoma)
102
Increased supratentorial pressure (tumor) forces the hippocampal uncus through the tentorial notch and compresses the oculomotor nerve. When this occurs, what fibers are affected first, resulting in a dilated and fixed pupil?
Pupilloconstrictor fibers
103
Which cranial nerve has cell bodies in the superior ganglion and inferior (petrosal) ganglion?
Glossopharyngeal / CN IX
104
Determine the corresponding descriptions of the components of the facial nerve
1. Projects centrally to the solitary tract and nucleus
2. Associated with lacrimal pathway & submandibular pathway
3. Innervates the posterior surface of the external ear via the posterior auricular branch of facial nerve
4. Innervates the soft palate and adjacent pharyngeal wall
5. Innervates muscles of facial expression, stylohyoid muscle, posterior belly of the digastric muscle and stapedius muscle
A. General somatic afferent
B. General visceral afferent
C. Special visceral afferent
D. General visceral efferent
E. Special visceral efferent
1. C
2. D
3. A
4. B
5. E
105
Determine the corresponding descriptions of the components of the glossopharyngeal nerve
1. Innervates the stylopharyngeus muscle; arises from nucleus ambiguus
2. Projects its central processes to the solitary tract and nucleus
3. Afferent limb of the gag reflex and the carotid sinus reflex
4. Projects its central processes to the spinal trigeminal tract and nucleus
5. Parasympathetic component that innervates the parotid gland
A. General somatic afferent
B. General visceral afferent
C. Special visceral afferent
D. General visceral efferent
E. Special visceral efferent
1. E
2. C
3. B
4. A
5. D
106
Which division of the trigeminal nerve is purely sensory in function?
Ophthalmic division / V1
