Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy Midterm 2 > Cranial Nerves > Flashcards

Cranial Nerves Flashcards

1
Q

Cranial Nerves

A

12 pairs

  • essentially run the functions of the head & neck
  • pure sensory, pure motor, or mixed
  • arise from & interact with nuclei (motor, sensory, parasympathetic) in brainstem (*NO SYMPATHETIC)
  • cell bodies of sensory neurons live in CN ganglia (like dorsal root ganglia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The 12 Cranial Nerves

A 
I - Olfactory
II - Optic 
III - Oculomotor
IV - Trochlear
V - Trigeminal
VI - Abducens
VII - Facial
VIII - Audiovestibular (Vestibulocochlear)
IX - Glossopharyngeal
X - Vagus
XI - Spinal Accessory
XII - Hypoglossal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

I - Olfactory Nerve

A
  • pure sensory
  • receptors in roof of nasal cavity
  • olfactory nerves supply olfactory epithelium
  • terminate in olfactory bulb –> olfactory tract
  • only sensory system to bypass thalamus (sensory relay station)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Damage/Disease to Olfactory Nerve

A

hyposmia - reduced sense of smell

anosmia - absence of sense of smell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

II - Optic Nerve

A
  • pure sensory
  • receptors in retina of eye
  • axons of ganglion cells –> optic nerve
  • optic nerve –> optic chiasm –> optic tract –> lateral geniculate nucleus (thalamus) –> optic radiations –> primary visual cortex
  • visual fields projected onto visual cortex in inverted and reversed fasion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Primary Visual Cortex

A

medial aspect of occipital lobe on either side of Calcarine Sulcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Damage/Disease to Optic Neve

A

results in visual field defects - depends on location of damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

III - Oculomotor Nerve

A
  • motor and parasympathetic (mixed)
  • arises from midbrain
  • motor to extra-ocular muscles (innervates all except LR6SO4 - lateral rectus CN VI, superior oblique CN IV)
  • PS to pupillary constriction & accomodation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Extra-Ocular Muscles supplied by Oculomotor Nerve

A
  • medial rectus
  • superior rectus
  • inferior rectus
  • inferior oblique
  • levator palpebrae superioris (elevator of upper eyelid)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Damage/Disease to Oculomotor Nerve

A 
pupilarry dilation (unstopped sympathetics)
opthalmoplegia (eye movements weakened or paralyzed)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

IV - Trochlear Nerve

A
  • smallest cranial nerve
  • pure motor
  • supplies superior oblique
  • only CN to emerge from back of brainstem (midbrain)
  • isolated damage uncommon (sandwiched btwn 2 layers of dura mater)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

VI - Abducent Nerve

A
  • pure motor
  • supplies lateral rectus (abducts eye = abducent)
  • longest intracranial course of all CNs - more able to have function compromised
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Damage to Abducent Nerve

A
  • paralysis of lateral rectus –> unopposed action of medial rectus –> eye deviates medially –> squint
    patients complain of double vision (diplopia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

V - Trigeminal Nerve

A
  • mixed nerve - sensory and motor from pons
  • 3 divisions arising from trigeminal ganglion: V1 - opthalmic nerve (eye), V2 - maxillary nerve (cheek), V3 - mandibular nerve (mandible)
  • serves as a conduit for parasympathetic functions of CNs III, VII, and IX
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Damage/Disease to Trigeminal Nerve

A

Trigeminal Neuraglia (Tic Douloureux)

  • pain, mainly in V2 and V3
  • sometimes only way to correct is to cut off sensation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

V1

A

Opthalmic Nerve –> eye

  • pure sensory
  • supplies sensation of frontal and ethmoidal paranasal air sinuses
  • supplies sensory innervation (general - PTTP) to nasal cavity
  • supplies sensation to the upper eyelid, side of the nose, forehead, and scalp (supraorbital nerve)
  • has ciliary ganglion - parasympathetic for CN III
17
Q

V2

A

Maxillary nerve –> cheek

  • pure sensory
  • enters floor of orbit through inferior orbital fissue
  • supplies sensation to: maxillary air sinus, nasal cavity, lower eyelid, skin of cheek, upper lip (infraorbital nerve), maxillary teeth and gums
  • has pterygopalatine ganglion - PS for CN VII
18
Q

V3

A

Mandibular nerve –> mandible

  • mixed nerve - sensory and motor
  • submandibular (CN VII) & otic (CN IX) ganglia (PS)
  • enters infratemporal fossa (medial to mandible)
19
Q

Functions of V3

A

Motor:
- supplies muscles of mastication
Sensory:
- lower lip, skin of mandible
- mandibular teeth & gums (inferior alveolar nerve)
- general sensation to anterior 2/3 of tongue (lingual nerve)
- ends as mental nerve
- carries proprioceptive info from muscles of mastication –> brainstem (force of bite)

20
Q

VII - Facial Nerve

A
  • mixed nerve (motor, sensory & PS)
  • attached to pons
  • cell bodies in geniculate ganglion
21
Q

Damage/Disease to Facial Nerve

A
  • may loose taste, salivation, or lacrimation in one eye

- Bell’s Palsy (hemi-facial paralysis)

22
Q

Functions of VII

A

Motor:
- muscles of facial expression
Sensory:
- taste to anterior 2/3 of tongue (via chordae tympani - joins lingual n)
- some sensory to skin around ear
PS:
- lacrimal gland for tearing vis pterygopalatine ganglion (V2)
- submandibular & sublingual salivary glands via submandibular ganglion (V3)

23
Q

VIII - Vestibulocochlear Nerve

A
  • pure sensory, 2 components:
    1. Vestibular
    2. Conchlear
24
Q

Vestibular Component of VIII

A
  • supplies vestibular aparatus (semicircular canals & vestibule) –> balance equilibrium
  • disease: Meniere’s syndrome - vertigo, nausea, vomiting
25
Q

Cochlear Component of VIII

A
  • supplies organ of Corti in cochlea –> hearing
  • bilateral central pathway in brainstem carries this info to the temporal lobe –> primary auditory cortex
  • damage/disease: difficulty in localizing sound (deafness rare)
26
Q

IX - Glossopharyngeal Nerve

A
  • mixed (motor, sensory, & PS)
  • supplies tongue and pharynx
  • attached to medulla
  • regulates gag reflex
27
Q

Damage/Disease to IX

A

difficulty swallowing, loss of gag reflex

28
Q

Functions of IX

A 
Motor to one Muscle:
- stylopharyngeus (elevates pharynx)
Sensory (general):
- posterior 1/3 tongue, pharynx, palatine tonsils, carotid sinus & body (for carotid sinus reflex)
Sensory (special):
- taste to posterior 1/3 tongue
PS:
- supplies parotid gland via otic ganglion (V3)
29
Q

X - Vagus Nerve

A
  • mixed (motor, sensory, & PS)

- attached to medulla

30
Q

Damage/Disease to Vagus Nerve

A

difficulty with speech and swallowing

31
Q

Vagus Nerve Functions

A

Motor:
- to muscles of palate, pharynx, and larynx (from CN XI)
Sensory:
- to muscles of palate, pharynx, and larynx
- sensory to eardrum (can induce a vagal response)
- barareceptor to hollow organs (stomach and bowel)
- carries visceral afferents from the organs to the CNS (gut feeling)
PS:
- functions as the PS nerve for the viscera
- PS motor to smooth muscle in thoracic and abdominal organs up to distal part of transverse colon
- regulates heart rate (slows it down)

32
Q

XI - Spinal Accessory Nerve

A
  • motor function
  • attached to medulla & upper spinal cord
    Cranial Portion:
  • distributed with CNX (palate, pharynx, larynx)
    Spinal Portion:
  • spinal accessory nerve - supplies trapezius and sternocleidomastoid muscles in the neck
33
Q

Damage/Disease to XI

A

weakness when shrugging (elevating shoulders), turning head to one side against resistance

34
Q

XII - Hypoglossal Nerve

A
  • pure motor
  • attached to medulla
  • supplies the muscles of the tongue
35
Q

Damage/Disease to XII

A

inability to protrude tongue symmetrically

Anatomy Midterm 2 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions