Cranial Nerves Flashcards Preview

MD1 Neuroscience > Cranial Nerves > Flashcards

Flashcards in Cranial Nerves Deck (133)
1

What do the cranial nerves supply?

Somatic and visceral motor and sensory information to the head.

2

Which cranial nerves supply visceral sensory and motor innervation to the neck, chest and abdomen?

CNIX and CNX

3

Which cranial nerves are purely sensory?

CNI, II and VIII

4

Which cranial nerves are purely motor?

CNIII, IV, VI, XI and XII

5

Which cranial nerves are mixed sensory and motor?

CNV, VII, IX and X

6

Why do the mixed cranial nerves have multiple functions?

Because each cranial nerve contains many functional groups of fibres.

7

What are cranial nerves connected to centrally?

Cranial nerve nuclei

8

How are the cranial nerve nuclei organised?

Rostral to caudal roughly in order of the target tissues they are associated with, in columns of similar function.

9

Where are the motor nerve nuclei located in the brainstem?

In 3 columns close to the midline.

10

How are the 3 motor nerve nuclei columns arranged from medial to lateral?

Somatic, Branchial (gill) and visceral (autonomic)

11

Which structures are innervated by somatic motor nerves?

Extra-occular muscles and muscles of the tongue.

12

Which cranial nerves innervate the extra-occular muscles?

CNIII Occulomotor

CNIV Trochlear

CNVI Abducens

13

Which cranial nerve innervates the muscles of the tongue?

CNXII Hypoglossal

14

Which structures are innervated by branchial arch nerves?

Muscles of mastication

Muscles of facial expression

Muscles of pharynx and larynx

15

Which cranial nerve supplies the muscles of mastication?

Mandibular division of CNV (Trigeminal)

16

Which cranial nerve supplies the muscles of facial expression?

CN VII (Facial nerve)

17

Which cranial nerves supply the muscles of the pharynx and larynx?

CNIX (Glossopharyngeal nerve) and CNX (Vagus)

18

What is nucleus ambiguus?

Mostly a motor nucleus that lies behind the inferior olive.

It is the nucleus for CNIX (stylopharyngeus muscle) and CNX (levator palati muscle) that controls the pharynx and larynx.

19

What do the visceral efferents innervate?

Smooth muscles (autonomic)

20

Which nuclei comprise the visceral efferents?

CNIII - Edinger-Westfal nucleus

CNVII - Superior salivatory nucleus

CNIX - Inferior salivatory nucleus

CNX - Dorsal motor nucleus of the Vagus

21

Where are sensory nuclei located in the brainstem?

In 3 columns lateral to the medial 3 motor columns.

22

How are the 3 sensory nerve nuclei columns arranged from medial to lateral?

Visceral sensory

Somatic sensory

Special sensory

23

Which structures are innervated by the visceral afferent nerves?

Taste

Autonomic

24

Which cranial nerves are responsible for taste visceral afferents?

CNVII (Facial)

CNIX (Glossopharyngeal)

CNX (Vagus)

25

Which cranial nerves are responsible for autonomic visceral afferents?

CNX (Vagus)

CNIX (Glossopharyngeal)

26

How many nuclei are there in the visceral sensory column?

One (does both taste and autonomic from CNVII, IX and X)

27

Which nucleus is responsible for general visceral sensation in the visceral sensory column?

Nucleus solitarius

28

Where does the nucleus solitarius extend between?

From the pons to the level of nucleus gracilis

29

What are the two divisions of nucleus solitarius

Rostral: gustatory nucleus Caudal: visceral sensory division

30

What does the rostral aspect of nucleus solitarius contain?

Gustatory nucleus: Primary afferents receiving input from taste buds and the palate (i.e.CNVII, IX and X)

31

What does the caudal aspect of nucleus solitarius contain?

Visceral sensory division: CNX: afferents from heart; abdominal viscera

CNIX: baroreceptors & chemoreceptors from carotid body and sinus

32

What does the somatic sensory column receive sensory information on?

Sensation to face, forehead, mucosa of nose & mouth, most of cranial dura: CNV (Trigeminal)

Skin behind ear and lining of external auditory meatus: CNVII (Facial), CNIX (Glossopharyngeal) and CNX (Vagus)

33

Which cranial nerves does the somatic sensory column receive information from?

CNV (Trigeminal)

CNVII (Facial)

CNIX (Glossopharyngeal)

CNX (Vagus)

34

Which sensory information does the special sensory column receive?

Smell: CNI (Olfactory)

Vision: CNII (Optic)

Hearing & Equilibrium: CNVIII (Vestibulocochlear)

35

Which cranial nerve nuclei arise originate from the midbrain?

CNIII and IV

36

Which cranial nerve nuclei arise originate from the pons?

CNV, VI, VII and CNVIII

37

Which cranial nerve nuclei arise originate from the medulla?

CNVIII, CNIX, CNX and XII

38

Which cranial nerves does nucleus solitarious receive?

Visceral afferents: CNVII, IX and X

39

Which cranial nerves does nucleus ambiguus receive?

Motor: CNIX and X

40

What is CNI's name?

Olfactory

41

What is CNII's name?

Optic

42

What is CNIII's name?

Oculomotor

43

What is CNIV's name?

Trochlear

44

What is CNV's name?

Trigeminal

45

What is CNVI's name?

Abducens

46

What is CNVII's name?

Facial

47

What is CNVIII's name?

Vestibulocochlear

48

What is CNIX's name?

Glossopharyngeal

49

What is CNX's name?

Vagus

50

What is CNXI's name?

Accessory

51

What is CNXII's name?

Hypoglossal

52

What causes the most common disruption to CNI?

Common cold

53

Which nerve is the olfactory nerve?

CNI

54

What does the olfactory nerve do?

Sense of smell (special sensory column)

55

Where does the olfactory nerve exit the skull?

Cribiform plate

56

Where does the olfactory nerve project to in the brain?

Gustatory cortex in the insular cortex

57

Which nerve is the optic nerve?

CNII

58

What type of nerve is the optic nerve?

Special sensory

59

What does the optic nerve do?

Vision

60

Where does the optic nerve project to in the cortex?

V1 in the occipital lobe

61

What cells in the retina are responsible for light transduction?

Ganglion cells

62

What happens to some axons of the optic nerve within the optic chiasm?

They cross

63

Where do optic nerve axons travel to after the optic chiasm?

To the lateral geniculate nucleus within the thalamus

64

Where do axons project to after the lateral geniculate nucleus?

Visual cortex (V1)

65

What are the 6 extra-ocular mucles?

Superior rectus; inferior rectus Medial rectus; lateral rectus Superior oblique; inferior oblique

66

What are the 3 cranial nerves of ocular motion?

CNIII - Oculomotor

CNIV - Trochlear

CNVI - Abducens

67

What do the nerves to extra-ocular muscles do?

Act in a coordinated fashion

68

Where do the nerves to extra-ocular muscles exit the skull?

Superior orbital fissue

69

Where does the optic nerve exit the skull?

Optic canal

70

Which extra-ocular muscles does the trochlear nerve innervate?

Superior oblique

71

Which extra-ocular muscles does the abducens nerve innervate?

Lateral rectus

72

Which nerve is the oculomotor nerve?

CNIII

73

What type of nerve is the oculomotor nerve?

Somatic motor and visceral motor (PS)

74

What does the oculomotor nerve do?

Motor: extra-ocular eye muscles MR, SR, IR and IO Elevates eye-lid via levator palpebrae superioris

PS to eye: - Iris (pupils) - Ciliary muscle (focussing)

75

In which brainstem column do the oculomotor nerves involves in PS to the eye sit?

Visceral efferent column

76

Where do all 3 extraocular motor nerves travel?

Go through the cavernous sinus and superior orbital fissure.

III and VI go through the common tendinous ring.

77

Which nerves enter the orbit via the superior orbital fissure?

CNIII, IV, VI and V1

78

Where is the superior orbital fissure located?

Between the greater and lesser wings of sphenoid.

79

What do cranial nerves often exit in?

Groups

80

Which cranial nerves exit the skull via the auditory canal?

CNVII and VIII

81

Which cranial nerves exit the skull via the jugular foramen?

CNIX, X and XI

82

Which cranial nerve exits the skull via the hypoglossal foramen?

CNXII

83

Which nerves are involved in the pupillary light reflex?

Sensory inputs to brain from the retina via CNII.

Motor outputs to Sphincter Pupillae muscle in iris.

PS fibres from Edinger Westfal nucleus.

84

Which nerve is the trigeminal nerve?

CNV

85

What type of nerve is the trigeminal nerve?

Somatic sensory and branchial motor

86

What does the trigeminal nerve do?

Sensory: input from the face and inside of mouth Motor: muscles of mastication. Tensor tympani (inner ear)

87

Where do the trigeminal nuclei run?

From midbrain to upper spinal cord

88

What are the 4 nuclei within the trigeminal nucleus?

Mesencephalic

Chief sensory

Spinal trigeminal nucleus (STN)

Motor nucleus

89

What do the chief sensory and STN nuclei of the trigeminal nucleus provide?

Sensory system to the face and head.

90

What are the chief sensory and STN nuclei of the trigeminal nucleus analogous with?

Dorsal column and anterolateral system.

91

What does the motor nucleus of the trigeminal nucleus provide?

Motor (branchial) efferents (located closer to midline)

92

What are the roots that the trigeminal nerve exits the brainstem as?

Motor and sensory

93

Where do the sensory roots of the trigeminal nerve travel to?

Trigeminal ganglion

94

What does the trigeminal ganglion give off?

3 Branches:

V1 - ophthalmic division

V2 - maxillary divison

V3 - mandibular division

95

With which division does the motor branch of the trigeminal nerve travel?

Mandibular division

96

What does the motor division of the trigeminal nerve innervate?

Muscles of mastication and tensor tympani (inner ear)

97

Where do the branches of the trigeminal nerve exit the skull?

V1: Superior orbital fissure

V2: Foramen rotundum

V3: Foramen ovale

98

What is involved in the corneal blink reflex?

Sensory inputs to brainstem via CNV1.

Motor outputs to eyelid (obicularis oculi) via CNVII.

Used as a test of pontine function.

99

Which nerve is the facial nerve?

CNVII

100

What type of nerve is the facial nerve?

Branchial motor

Visceral efferent

Visceral sensory (taste)

Somatic sensory

101

What are the two functional divisions to the facial nerve?

Motor (facial nerve proper) nervus intermedius: parasympathetic, taste and sensation.

102

What does the motor component of the facial nerve do?

Branchial motor: innervates the muscles of facial expression, stapedius muscle (ear) and part of digastric muscle.

103

What does the nervus intermedius component of the facial nerve do?

Provides information on:

Parasympathetic: lacrimal, sublingual and submandibular glands

Taste: from anterior 2/3rds of tongue and soft palate

Sensation: from a small region near the external auditory meatus.

104

What are the terminal branches of the facial nerve that innervate muscle?

Posterior auricular

Temporal

Zygomatic

Buccal

Mandibular

Cervical

105

What role does the facial nerve play in the corneal reflex?

It closes the eye via the temporal branch.

106

What do the terminal branches of the facial nerve all pass through?

The parotid

107

True or false: the facial nerve innervates the parotid.

False.

108

Which cranial nerve is the vestibulocochlear nerve?

CNVIII

109

What does the vestibulocochlear nerve do?

Hearing and balance

110

What type of nerve is the vestibulocochlear nerve?

Special sensory

111

Which nuclei give rise to the vestibulocochlear nerve?

Dorsal and ventral cochlear nuclei and 4 vestibular nuclei.

112

Where does the vestibulocochlear nerve exit the skull?

Internal acoustic meatus

113

What is the most common cause of gradual hearing loss?

Acoustic neuroma

114

Which cranial nerve is the glossopharyngeal nerve?

CNIX

115

What does the glossopharyngeal nerve do?

Sensory from tongue (post. 1/3), pharynx, middle ear and carotid body.

Taste: post. 1/3 of tongue

Visceral motor: PS to parotid

Motor: stylopharyngeus

116

Where does the glossopharyngeal nerve exit the skull?

Jugular foramen

117

Where does the glossopharyngeal nerve exit the skull in relation to CNX and CNXI?

In the jugular foramen, lateral and anterior to CNX and CNXI.

118

What is the pathway of the glossopharyngeal nerve?

Exits the skull via jugular foramen and follows stylopharyngeus muscle to reach the oropharynx and the tongue.

119

What are the nuclei giving rise to the glossopharyngeal nerve?

Superior and inferior ganglia (containing afferent components of the nerve).

120

Which cranial nerve is Vagus?

CNX

121

What type of nerve is Vagus?

Branchial motor

Visceral motor (PS)

Somatic sensory

Visceral sensory (special) taste

Visceral sensory (general)

122

What does vagus do?

Motor: to many striated muscles - soft palate, pharynx, larynx, upper oesophagus and 1 tongue muscle.

PS to many organs: from pharynx to upper abdomen

Sensory: from pharynx, larynx and oesophagus

Visceral: input from baro- and chemoreceptors of the aortic arch.

123

What is the majority of Vagus' function?

Autonomic

124

Which pathways are involved in the gag reflex?

Sensory inputs: CNIX - sensory to pharynx

Motor outputs: CNX - motor to pharynx

125

What is the gag reflex used to test?

Medulla function

126

Which cranial nerve is the spinal accessory nerve?

CNXI

127

Where is the spinal accessory nucleus?

In the upper 5-6 of cervical spinal cord.

128

What is the course of the spinal accessory nerve?

Enters cranium via foramen magnum and then travels with CNX roots and exits at the jugular foramen.

129

What does the spinal accessory nerve do?

Provides motor input to sternocleidomastoid and upper part of trapezius.

130

Which cranial nerve is the hypoglossal nerve?

CNXII

131

What type of nerve is the hypoglossal nerve?

Somatic motor

132

What does the hypoglossal nerve do?

Motor innervation to intrinsic and extrinsic muscles of the tongue (except palatoglossus - CNX). It is the main somatic nerve to the tongue.

133

Where does the hypoglossal nerve exit the skull?

Hypoglossal foramen