Control L7 cranial nerves Flashcards
1
Q
Which 10 cranial nerves emerge from the brainstem?
A
CN III - XII
2
Q
What cranial nerves are part of the CNS?
A
CN I & II
3
Q
What part of the nervous system are cranial nerves that derive from the brainstem part of? (Central/peripheral)
A
Peripheral
4
Q
Where did the optic nerve (CN II) develop from?
A
Diencephalon
5
Q
Where do the olfactory bulb and olfactory tract of CN I originate from?
A
Telencephalon
6
Q
For each fibre type within a CN, there is a corresponding nucleus in the brainstem. True or false?
A
True
7
Q
How many nuclei are associated with the occulomotor nerve?
A
2 - one for somatic motor fibres (occulomotor nuclei) and the other (Edinger-Westphal nuclei) for the autonomic visceral motor fibres
8
Q
Where on the brainstem are sensory nuclei located?
A
Laterally
9
Q
Where on the brainstem are motor nuclei located
A
Medially
10
Q
What part of the brainstem are cranial nerve nuclei located?
A
Tegmentum
11
Q
How many cranial nerve nuclei are in the brainstem?
A
17
12
Q
Where are cranial nerve nuclei found in relation to the ventricular system?
A
anteriorly
13
Q
What are three examples of motor nuclei found in the open medulla?
A
Somatic motor
Parasympathetic motor
Head and neck motor
14
Q
What are three examples of sensory nuclei found in the open medulla?
A
Special sensory
Somatic sensory
Visceral sensory
15
Q
What innervation is the somatic motor nuclei involved in?
A
Somatic skeletal muscles
16
Q
What innervation is the parasympathetic motor nuclei involved in?
A
Secretion of glands
17
Q
What innervation is the head and neck motor nuclei involved in?
A
Some muscles of the head and neck
18
Q
What innervation is the special sensory nuclei involved in?
A
Senses (smell, vision, taste, hearing, balance)
19
Q
What innervation is the somatic sensory nuclei involved in?
A
General sensation (touch) from the peripheries
20
Q
What innervation is the visceral sensory nuclei involved in?
A
Sensation of internal organs and glands
21
Q
What innervation is the branchial motor nuclei involved in?
A
Muscles derived from pharyngeal arches
22
Q
How many CN are purely motor (efferent) fibres?
A
5
23
Q
How many CN are purely sensory (afferent) fibres?
A
3
24
Q
How many CN are a mix of efferent and afferent fibres?
A
4
25
Which part of the brainstem are CN nuclei found?
All parts - medulla, pons and midbrain
26
What is CN I?
Olfactory nerve
27
Where does CN I originate from?
the nasal mucosa
28
How does CN I communicate with the brain?
nerve travels from the nasal mucosa, merges with the olfactory bulbs and olfactory tract which are extensions of the telencephalon
29
What foramina does CN I pass through?
cribriform plate
30
What type of nuclei does CN I have?
Special sensory
31
What is the function of CN I?
olfaction aka smell
32
How can you test the function of CN I?
with a smell test e.g. an orange
33
What is the term for not being able to smell?
Anosmia
34
What is CN II?
Optic nerve
35
Where does CN II originate?
The retina
36
How does CN II communicate with the brain?
Emerges from the retina and travels to the optic chiasma into the optic tracts carrying visual information to the thalamus
37
What part of the brain are CN II extensions of?
diencephalon
38
What foramina do CN II travel through?
Optic canal
39
What type of nuclei does CN II have?
Special sensory
40
What is the function of CN II?
vision
41
How do we test the function of CN II?
Various visual tests
42
What is the only sensory modality that does not travel through the thalamus?
Smell/olfaction
43
What is CN III?
Occulomotor
44
Where does CN III emerge?
Pontomesencephalic junction (where pons and midbrain meet)
45
What foramen does CN III travel through?
superior orbital fissure
46
What nuclei are found in CN III?
somatic motor and visceral parasympathetic motor
47
What muscles are supplied by CN III?
the four extraocular muscles and Levator palpebrae superioris (somatic motor fibre)
Ciliary muscle and sphincter pupillae (parasympathetic autonomic motor fibres)
48
What is CN IV?
Trochlear
49
Where does cranial nerve IV emerge from?
Dorsal midbrain
50
What foramen does CN IV travel through?
Superior orbital fissure
51
What nuclei are found in CN IV?
somatic motor
52
What muscle is supplied by CN IV?
superior oblique muscle
53
What is CN VI?
Abducens
54
Where does CN VI emerge?
pontomedullary junction (where pons and medulla meet)
55
What foramen does CN VI travel through?
superior orbital fissure
56
What nuclei is found in CN VI?
somatic motor
57
What muscle is supplied by CN VI?
Lateral rectus
58
How is function of CN III, IV and VI tested?
Follow finger (H) test
59
How do signals reach the ciliary muscles and sphincter pupillae from CN III?
The preganglionic fibres of CN III travel to the ciliary ganglion and the postganglionic fibres then travel to the muscles to innervate
60
What muscle closes the eyelid?
Orbicularis oculi
61
What CN is involved in closing the eyelids/ innervating orbicularis oculi?
CN VII
62
What muscle opens the eyelid?
Levator palpebrae superioris
(+ superior tarsal muscle sympathetically - e.g. in surprise, fear or excitement - by elevating upper eyelid)
63
Which muscle keeps the eyelid open?
Superior tarsal muscle
64
What CN is involved in innervating levator palpebrae superioris in opening/dilating the superior eyelid?
CN III (motor fibres)
65
What muscles dilate the pupil?
The dilators of the iris
66
Are the dilators of the iris innervated parasympathetically or sympathetically?
Sympathetically
67
What muscles are involved in constricting the pupil and changing the lens shape?
Sphincter pupillae and the ciliary muscle
68
Are sphincter pupillae and the ciliary muscle innervated sympathetically or parasympathetically?
Parasympathetically
69
What is CN V called?
Trigeminal nerve
70
How many subdivisions does the trigeminal nerve have?
3
71
What are the three subdivisions of the trigeminal nerve?
Opthalmic (V1)
Maxillary (V2)
Mandibular (V3)
72
Where does CN V emerge from?
The lateral sides of the pons
73
What foramen does CN V1 travel through?
Superior orbital fissure
74
What foramen does CN V2 travel through?
Foramen rotundum
75
What foramen does CN V3 travel through?
Foramen ovale
76
What nuclei are found in CN V?
Somatic sensation in V1, V2 and V3
Branchial motor in V3
77
What is the function of CN V1?
Sensation of upper face (above eye)
78
What is the function of CN V2?
sensation from middle face (between eye and mouth)
79
What is the function of CN V3?
Sensation from lower face, mandible and anterior 2/3 of the tongue
Innervation of muscles including muscles of mastication, anterior belly of the digastric muscle and tensor tympani.
80
How do you test for function of CN V?
V1 = cotton wool on forehead and corneal reflex test
V2 = cotton wool on cheek
V3 = cotton wall on jaw, clench teeth and feel masseter muscle, move jaw side to side against resistance to test pterygoid muscles, protrude jaw and jaw jerk reflex.
81
What are four autonomic ganglia associated with CN V?
Ciliary
Pterygopalatine
Submandibular
Otic
82
What is CN VII called?
Facial nerve
83
Where does CN VII emerge from?
The cerbellopontine angle (medially to CN VIII)
84
What foramen does CN VII enter the skull?
Internal acoustic meatus
85
What foramen does CN VII exit the skull?
Stylomastoid foramen
86
What nuclei are found in CN VII?
Branchial motor, visceral parasympathetic motor, special sensory and somatic sensory
87
What is the branchial motor function of CN VII?
Innervate muscles of facial expression, strapedius muscle, posterior belly of the digastric muscle
88
What is the visceral parasympathetic motor function of CN VII?
Innervate all glands (except parotid) to secrete
89
What is the special sensory function of CN VII?
Taste on anterior 2/3 of tongue via chorda tympani
90
What is the somatic sensory function of CN VII?
Sensation to skin of ear
91
How do you test function of CN VII?
Test facial movements and expressions, taste and salivation
92
What is CN VIII called?
Vestibulocochlear
93
Where does CN VIII emerge from?
The cerebellopontine angle (laterally to CN VII)
94
What foramen does CN VIII travel through?
Internal acoustic meatus
95
What nuclei are found in CN VIII?
Special sensory
96
What is the function of CN VIII?
Hearing and balance
97
How do you test the function of CN VIII?
bedside hearing tests like Rinne’s and Weber’s
98
What is the name of CN IX?
glossopharyngeal
99
Where does CN IX emerge from?
Posterolateral sulcus of medulla, lateral to the olives
100
What foramen does CN IX travel through?
jugular foramen
101
What nerve fibres are found in CN IX?
Branchial motor, visceral parasympathetic motor, special sensory, somatic sensory and visceral sensation
102
What is innervated by the branchial motor fibres of CN IX?
Pharynx in order to swallow
103
What is innervated by the visceral parasympathetic motor fibres of CN IX?
Parotid gland
104
What is innervated by the special sensory fibres of CN IX?
The middle ear, pharynx and posterior 1/3 of the tongue
105
What is innervated by the visceral sensation fibres of CN IX?
the carotid body and carotid sinus monitoring O2 sats and BP.
106
How can the function of CN IX be tested?
Assessing gag reflex
107
What is CN X called?
Vagus nerve
108
Where does CN X emerge from?
The posterolateral sulcus of the medulla laterally to the olives (inferior to CN IX)
109
What foramen does CN X travel through?
Jugular foramen
110
What nerve fibres does CN X contain?
Branchial motor, visceral parasympathetic motor, visceral sensory, special sensory and somatic sensory
111
What does the branchial motor fibres of CN X innervate?
the muscles of the pharynx, larynx and soft palate and uvula
112
What do the visceral parasympathetic motor fibres of CN X innervate?
Thoracic and GI tract muscles
113
What do the visceral sensory nerve fibres of CN X innervate?
Thoracic and GI sensation
114
What do the special sensory fibres of CN X innervate?
Taste from epiglottis and palate
115
What do the somatic sensory fibres of CN X innervate?
Sensation from epiglottis, larynx and skin of external ear
116
How do you test the function of CN X?
Assessing speaking and movement of the uvula
117
What is CN XI called?
Accessory nerve
118
Where does CN XI emerge from?
The caudal medulla and rostral spinal cord
119
What foramen does CN XI travel through?
Jugular foramen
120
What nerve fibres are found in CN XI?
Somatic motor
121
What does CN XI innervate?
Motor function of sternocleidomastoid and trapezius muscles
122
How do you test for the function of CN XI?
By assessing ability to shrug shoulders and rotate head against resistance.
123
What is CN XII called?
Hypoglossal
124
Where does CN XII emerge from?
anterolateral sulcus between the pyramids and the olives
125
What foramen does CN XII travel through?
Hypoglossal canal
126
What nerve fibres are found in CN XII?
somatic motor
127
What is the function of CN XII?
Motor Innervation of muscles of the tongue
128
How do you test for the function of CN XII?
Assess protrusion of the tongue.
129
Which spinal roots contribute to CN XI?
Spinal roots of C1-C5
130
How do the spinal roots join with CN XI?
Travel up through the foramen magnum into the skull and combines with the cranial root to form CN XI before leaving via the jugular foramen
131
If damage to the CN XII, which side does the tongue protrude towards?
The paralysed side
132
Which cranial nerves contain preganglionic autonomic fibres?
III
VII
IX
X
133
What ganglia is associated with CN III?
Ciliary
134
What ganglion is associated with CN VII?
Pterygopalatine
135
What ganglion is associated with CN IX?
Submandibular
136
What ganglion is associated with CN X?
Otic
137
What nerve do the postganglionic autonomic fibres of the ciliary, pterygopalatine and submandibular ganglia travel with?
Trigeminal
138
What muscle and function is the ciliary ganglion associated with?
Pupil constriction by the sphincter pupillae
139
What gland and function is the pterygopalatine ganglion associated with?
Lacrimation via the lacrimal gland
140
What gland and function is the submandibular ganglion associated with?
salivation by the submandibular, sublingual, parotid gland
