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Flashcards in Cranial Nerves Deck (94)
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1
Q

12 cranial nerves

A

functionally similar to spinal nerves

2
Q

Cranial nerves

A
  1. in brainstem
  2. innervate muscles of head, neck, face, larynx, tongue, pharynx, & glands
  3. Essential for speech, resonance, & phonation, swallowing, vagus
3
Q

Optic nerve attachment to retina creates a ??

A

blind spot

4
Q

CN I

A

olfactory nerve: sensation of smell

5
Q

CN II

A

optic nerve: visual sensation

6
Q

CNIII

A

oculomotor nerve: motor nerve, eyeball movement

7
Q

CN IV

A

trochlear nerve: motor nerve, eyeball movement

8
Q

CN V

A

trigeminal nerve: sensory (head, face, oral) and motor (jaw movement)

9
Q

CN VI

A

abducens: motor nerve, eye movement through lateral rectus muscle

10
Q

CN VII

A

facia: primarily motor, muscles of face, sensory-taste

11
Q

CN VIII

A

vestibulocochear: sensory: equilibrium and hearing

12
Q

CN IX

A

glossopharyngeal: motor (swallowing) and sensory (touch & taste from posterior third of tongue and pharynx)

13
Q

CN X

A

Vagus: motor and sensory for pharynx, larynx, and soft palate

14
Q

CN XI

A

spinal accessory: motor nerve

-muscles contolling head movement

15
Q

CN XII hypoglossal nerve

A

motor nerve for muscles of tongue

16
Q

Cranial nerve nuclei: midbrain 3 nuclei

A
  1. edinger-westphal nucleus
  2. oculomotor nucleus
  3. trochlear nucleu
17
Q

Pons: 7 major nuclei

A

Trigeminal nerve, primary nucleus (spinal trigeminal and mesencephalic nuclei), abducens motor, and facial

18
Q

Medulla: 9 major nuclei

A
  1. cochlear and vestibular nuclear complexes
  2. solitarius nucleus
  3. salivatory nucleus (ANS)
  4. hypoglossal nucleus
  5. ambiguus nucleus
  6. spinal trigeminal nucleus
19
Q

Corticonuclear (bulbar fibers)

A

cortex to brainstem

20
Q

Corticonuclear fibers

A

UMNs, LMNs

-Descend through internal capsule-genu

21
Q

Sensory Pathways

A

three-order nuclei & fibers (moving from lower to upper)

22
Q

first-order fibers

A

outside the CNS (tickle on the face)

23
Q

Second-order fibers

A

brainstem gray matter: ducussating second-order fibers (right cheek tickle meets up w/ left cheek thalamus and crosses)

24
Q

Third-order fibers

A

projections from the thalamus to the sensory cortex

25
Q

UMNs

A

syndromes affect nerves from cortex to brainstem

26
Q

LMNs

A

brainstem to face

27
Q

3 sensory pathways (first, seond, third) and how many motor?

A

2: UMN and LMN

28
Q

Complex Motor Innervation/Bilateral corticonuclear innervation

A

facial, trigeminal, vagus, glossopharyngeal

29
Q

Complex/BilateralFacial innervates

A

upper face

30
Q

Trigeminal innervates

A

masticators

31
Q

Vagus innervates

A

pharynx & larynx

32
Q

Glossopharyngeal innervates

A

pharynx

33
Q

Unilateral corticonuclear innervation

A

facial, spinal accessory, hypoglossal, ocular muscles (oculomotor, trochlear, abdusence)

34
Q

Unilateral facial innervates

A

lower facial muscles

35
Q

Spinal accessory innervates

A

Sternocleidomastoid and trapezius muscles

36
Q

Hypoglossal innervates

A

lingual muscles

37
Q

oculomotor, trochlear, and abdusence innervate

A

ocular muscles

38
Q

Conjugate gaze center

A

cortinoculear projections for the coordination of both eyes

39
Q

Trigeminal nerve Function

A

sensory- face, head, oral, orbital cavities

motor-muscles of mastication/chewing

40
Q

Trigeminal nerve structures/complex

A
  1. primary sensory nucleus
  2. spinal nucleus
  3. mesencephalic nucleus
41
Q

Sensory portion of trigeminal nerve

A
  1. thalamic
  2. maxillary
  3. mandibular
42
Q

2nd order neurons of trigeminal

A
  1. principle trigeminal nucleus
  2. mesencephalic
  3. spinal trigeminal
43
Q

principle trigeminal nucleus

A

TOUCH

  • most cross contralateral thalamuc nucleus
  • some sensory info from teeth and jaws goes to thalamus
44
Q

mesencephalic

A

PROPRIOCEPTION

-bilateral: biting, chewing, swallowing are all symmetrical

45
Q

spinal trigeminal

A

PAIN

-contralateral thalamus

46
Q

Clinical probs w/ Trigeminal Nerve

A
  1. Trigeminal neuralgia
  2. Peripheral branch damage
  3. Special Visceral (Branchial) Efferent
  4. Motor Nucleus damage
  5. Unilateral cortical or corticonuclear injury
  6. Bilateral cortical (UMN) or LMN lesion
47
Q

Trigeminal neuralgia

A

tic douloureux-chronic pain sensation of unknown etiology

48
Q

Sensation/touch damage to Peripheral branch

A

Ipsilateral loss of sensation-face, tongue, teeth, mouth, gum & cavities oral/orbital

49
Q

Testing Peripheral branch damage

A

Stimuli of cotton, pin prick, & reflexes (sneeze & corneal)

50
Q

Special Visceral (Branchial) Efferent/ damage to Trigeminal

A

motor nucleus, masticators, Tensor veli palatini (preventing food from nasopharynx) and tensor tympani (restricting malleus motion on exposure to loud sound)

51
Q

Motor nucleus damage/ Trigeminal nerve

A

LMN syndrome: paralysis of ipsilateral masticators w/ jaw deviation to site of injury: deviation obvious upon jaw protrusion
-muscles twitch, gradually atrophy, and jerk/reflex absent

52
Q

Unilateral cortical or corticonuclear injury has mild effect on jaw strength/trigeminal nerve

A

due to bilatera innervation

53
Q

Bilateral control (UMN) or LMN lesion/Trigeminal nerve damage

A

bilateral jaw paralysis

54
Q

Testing trigeminal nerve damage for motor damage

A

lateral & frontal jaw movement against resistance, also can be test phones requiring jaw support (bilapials, labiodental, dentals, and palatals)

55
Q

Facial Nerve Function

A

Motor: muscles of face, scalp & stapeius: kissing, blowing, speaking, smiling, raising, eyebrows, emotional expressions, and swallowing

56
Q

Facial Nerve Function #2

A

Superior salivatory: paraysympathetic efferent to lacrimal, sublingual & submandibular glands & secretory glands in mouth & nasal cavities

57
Q

Facial Nerve function #3

A

Sensory: Nucleus Solitarius: Taste sensation: anterior 2/3 of the tongue

58
Q

Facial Innervation: corticobulbar

A
  1. lower face

2. upper face

59
Q

Frontal Innervation: lower face

A

contralateral innervation

60
Q

Frontal innervation: upper face

A

bilateral innervation

61
Q

Clinical Implications w/ UMN

A

paralysis in contralateral lower half of face w/ spared upper face

62
Q

Clinical implications w/ LMN or bilateral cortical lesion:

A

paralysis of upper & lower face

63
Q
Clinical correlates w/ Facial Nerve damage
#1:
A

Pons-affect all 3 (general visceral efferent, special visceral afferent, and special visual efferent) functions

64
Q

Clinical correlates w/ Facial Nerve damage #2:

A

Facial nerve beyond stylomastoid forament: paralysis of ipsilateral half of facial muscles, intact glandular secretion & taste sensation

65
Q

Clinical correlates w/ Facial Nerve damage #3:

A

General Visceral Efferent fibers: secretory dysfunctions of glands in eye & palate

66
Q

Clinical correlates w/ Facial Nerve Damage #4:

A

Interruption of efferents to middle ear-hyperacusia (normal sounds seem louder)

67
Q

Bells Palsy: facial nerve dysfunction

A

Lower Motor Neuron Syndrome: sudden onset of paralysis of ipsilateral upper and lower facial muscles

68
Q

Bells Palsy etiology

A

nerve degeneration, inflammation or infection of facial nerve

69
Q

Testing facial nerve damage by asking patient to

A

smile, part lips, show teeth, puff out cheeks, pucker lips, express emotions
-taste eval: salt, sugar, vinegar

70
Q

Vestibulochoclear Nerve Function

A

equilibrium and audition

71
Q

Vestibular nerve Fx: Special Somatic Afferent

A

maintains equilibrium, coordination of head and body, stabilization of visual fixation point during movement

72
Q

first order vestibular

A

superior & inferior vestibular ganglia

73
Q

second order vestibular

A

nuclei in caudal pons

74
Q

projections to ???/vestibular

A

MLF/ocular fixation & cerebellum/equilibrium

75
Q

Scarpas ganglion

A

nucleus for vestibular nerve/first order

76
Q

Auditory nerve

A

bilateral projections to cortex and tonotopic representation throughout path and auditory cortex-equally important descending fibers

77
Q

First order auditory nerve

A

spiral ganglia

78
Q

second order auditory nerve

A

cochlear nuclei in caudal pons

79
Q

3rd order is always the same: always goes to motor cortex!

A

ALWAYS GOES TO MOTOR

80
Q

Clinical correlates of vestbulacochlear nerve

A

equilibrium and audition

81
Q

Equillibrium of vestibulacoch

A

disturbances of equilibrium and impaired vertigo/dizziness

82
Q

Audition of vestibulocohelaer

A

conductive or sensorineural hearing loss, brainstem lesion-partial impariment (bilateral projections)

83
Q

Glossopharyngeal nerve function

A

functionally identical to vagus nerve

84
Q

Sensorimotor nucleus of glossopharyngeal nerve

A
  1. inferior salivatory nucleus
  2. nucleus ambiguus
  3. nucleus solitarius
85
Q

glossopharyngeal and vagus share a ?

A

ganglion-functionally same

86
Q

glossopharyngeal first order

A

inferior ganglion

87
Q

glossopharyngeal second order

A

nucleus solitarius

88
Q

glossopharyngeal

A

VPM of thalamus

89
Q

General Visceral Afferent of Glossopharyngeal

A

inputs from carotid body (chemoreceptors) in response to changes in blood carbon dioxide help control respiration rate
-carotid sinus baroreceptors respond to increased blood pressure and control blood flow

90
Q
  1. Nucleus Solitarius of glossopharyngeal
A

taste sensation from posterior third of tongue and oral pharynx

91
Q
  1. Inferior Salivatory Nucleus of glossopharyngeal
A

controls glands and cardiac muscles, regulates secretion from parotid gland and secretion from oral pharynx

  • preganglionic parasympathetic projections to inferior salivatory nucleus
  • postganglionic projections to otic ganglion (parotid secretion)
92
Q
  1. Nucleus Ambiguus (branchial branch) of glossopharyngeal
A

nucleus ambiguus is rostral, bilaterally innervated, and regulates swallowing by projections to (ipsilateral stylopharyngeal muscle, upper pharyngeal constrictor fibers)

93
Q

Clinical correlates to glossopharyngeal

A
  1. discrete lesion
  2. loss of taste
  3. loss of gag reflex
  4. excessive oral secretion
94
Q

discrete lesion of glossopharyngeal

A

partial paresis of unilateral stylopharyngeal muscle (impairment of ipsilateral pharyngeal elevation in deglutition)