Cranial Nerves Flashcards Preview

Neuroscience Deja Review USMLE 1 > Cranial Nerves > Flashcards

Flashcards in Cranial Nerves Deck (66):
1

Associated cranial foramen for CN I

Cribiform plate

2

Associated cranial foramen for CN II

Optic canal

3

Associated cranial foramen for CN III, IV, V1, VI

Superior orbital fissure. Note: all of these nerves pass through the cavernous sinus as well.

4

Associated cranial foramen for CN V2

Foramen Rotundum

5

Associated cranial foramen for CN V3

Foramen Ovale (for divisions of the trigeminal nerve think “S tanding R oom O nly”)

6

Associated cranial foramen for CN VII, VIII

Internal acoustic meatus

7

Associated cranial foramen for CN IX, X, XI

Jugular foramen

8

Associated cranial foramen for CN XII

Hypoglossal canal

9

Function of CN I: olfactory

Smell

10

Function of CN II: optic

Vision

11

Function of CN III: oculomotor

1. Eye movement
2. “Parasympathetic” ciliary and pupillary sphincter mm
Note: mm is used as the abbreviation for “muscles”.

12

Function of CN IV: trochlear

Contraction of superior oblique muscle

13

Function of CN V1: trigeminal—ophthalmic branch

Sensation from nose to forehead

14

Function of CN V2: trigeminal—maxillary branch

Sensation from lateral nose, upper lip, superior buccal area

15

Function of CN V3: trigeminal—mandibular branch

1. Sensation from areas of the lower face not covered by V1 and V2
2. Movement of the Muscles of Mastication (Masseter, teMporalis, Medial, and lateral pterygoids), tensor veli palatini, and tensor tympani

16

Function of CN VI: abducens

Contraction of lateral rectus muscle

17

Function of CN VII: facial

1. Parasympathetic—lacrimal, submandibular, and sublingual glands
2. Mm of facial expression, stapedius, stylohyoid, and the posterior belly of the digastric muscle
3. Taste—anterior two-thirds of tongue
4. Sensation—skin of external ear

18

Function of CN VIII: vestibulocochlear

Hearing and sense of balance

19

Function of CN IX: glossopharyngeal

1. Parasympathetic—parotid gland
2. Motor—stylopharyngeus mm
3. Taste—posterior one-third tongue
4. Sensation—parotid gland, carotid body and sinus, pharynx, and middle ear
5. Cutaneous sensation—external ear canal

20

Function of CN X: vagus

1. Parasympathetic—trachea, bronchi, heart, GI tract
2. Contraction of laryngeal, pharyngeal, and esophageal striated mm
3. Taste—epiglottis and palate
4. Sensation—trachea, GI tract
5. Cutaneous sensation—external ear

21

Function of CN XI: accessory

Movement of sternocleidomastoid and trapezius muscles

22

Function of CN XII: hypoglossal

Contraction of muscles of tongue

23

Which three cranial nerves are purely sensory nerves?

1. CN I
2. CN II
3. CN VIII

24

Which five cranial nerves are purely motor nerves?

1. CNIII
2. CNIV
3. CNVI
4. CNXI
5. CNXII

25

Which four cranial nerves have both motor and sensory components?

1. CNV
2. CNVII
3. CNIX
4. CNX

26

Which two cranial nerves are rostral to the midbrain?

1. CNI
2. CNII

27

Which two cranial nerve nuclei are located in the midbrain?

1. CNIII
2. CNIV

28

Which four cranial nerves have at least a portion of their nuclei in the pons?

1. CNV
2. CNVI
3. CNVII
4. CNVIII

29

Which seven cranial nerves have at least a portion of their nuclei in the medulla?

1. CN V
2. CN VI
3. CN VII
4. CNVIII
5. CN IX
6. CNX
7. CNXII

30

Name the only cranial nerve that crosses the midline and exits the brainstem posterior to the ventricular system:

CN IV—exits the brainstem posteriorly and crosses the midline after exiting the caudal midbrain

31

What nucleus serves as the origin of preganglionic parasympathetic fibers projecting to the ciliary ganglion?

Edinger-Westphal nucleus of CN III

32

What visceral sensory nucleus, located in the medulla, is a relay center for taste, sensory input from the carotid sinus, carotid body, and the vagus nerve?

Nucleus Solitarius

33

What visceral motor nucleus, located in the medulla, is involved in coordinating swallowing and speech?

Nucleus aMbiguus

34

Which are the afferent and efferent limbs of the corneal reflex?

CN V1 and CN VII

35

Which are the afferent and efferent limbs of the pupillary light reflex?

CN II and CN III

36

Which are the afferent and efferent limbs of the gag reflex?

CN IX and CN X

37

What lesion causes Ipsilateral blindness

Transection of the optic nerve

38

What lesion causes Binasal hemianopia

Bilateral lateral compression of optic chiasm

39

What lesion causes Bitemporal hemianopia

Midsagittal transection or midline pressure on the optic chiasm (often caused by a pituitary tumor)

40

What lesion causes Right hemianopia without macular sparing

Transection of the left optic radiation

41

What lesion causes Right upper quadrantanopia

Transection of the lower division of the left optic radiation

42

What lesion causes Right lower quadrantanopia

Transection of the upper division of the left optic radiation

43

What lesion causes Right hemianopia with macular sparing

Destruction of the left visual cortex

44

What are five key structures of the pupillary light reflex pathway?

1. Ganglion cells of the retina
2. Pretectal nucleus of the midbrain
3. Edinger-Westphal nucleus
4. Ciliary ganglion
5. Postganglionic parasympathetic fibers of CN III

45

What are four key structures of the pupillary dilation pathway?

1. Paraventricular nucleus of the hypothalamus
2. Ciliospinal center of Budge at the level of T1 to T2
3. Superior cervical ganglion
4. Postganglionic sympathetic fibers traveling along the internal carotid artery and its branches to the eye

46

What part of the cortex is responsible for voluntary eye movements?

Frontal eye field (Brodmann area 8)

47

What side will a patient’s eyes deviate toward if there is a lesion of the right frontal eye field?

Right side (“Look toward the lesion of frontal eye fields”)

48

What structure connects the nucleus of CN VI and the nucleus of CN III?

Medial longitudinal fasciculus (MLF)

49

What type of lesion will result in medial rectus palsy (inability to adduct the eye) on attempted lateral gaze but normal adduction on accommodation?

Intranuclear ophthalmoplegia (a lesion of the MLF)

50

What classic idiopathic lesion is characterized by ptosis, miosis, and anhydrosis?

Horner syndrome

51

Name the condition characterized by a pupil that will accommodate but cannot react to light:

Argyll-Robertson pupil (associated with tertiary syphilis, lupus, and diabetes mellitus)

52

Name the condition caused by a lesion in the afferent fibers of the light reflex pathway:

Marcus Gunn pupil

53

What are the primary sensory receptors of the auditory pathway?

Inner hair cells of the organ of Corti

54

Where does the auditory pathway terminate?

Bilateral input from both auditory tracts terminates in primary auditory cortex in superior temporal gyrus (Brodmann areas 41 and 42)

55

What type of cells are responsible for relaying auditory stimuli from the organ of Corti to the cochlear nuclei?

Bipolar cells of the spiral or cochlearganglion

56

What thalamic nucleus plays a key role in relay of impulses from the cochlear nuclei to higher cortical centers?

Medial geniculate body of the thalamus

57

What pontine nucleus plays a key role in sound localization?

Superior olivary nucleus

58

What are key structures of the hearing pathway?

Cochlear → cochlear nucleus → decussating fibers in Trapezoid body → superior olivary nucleus → lateral lemniscus → inferior colliculi → medial geniculate nucleus → primary auditory cortex

59

Conduction deafness is caused by a lesion of which components of the auditory system?

External auditory canal, tympanic membrane, or the middle ear

60

Sensorineural deafness is caused by a lesion of which components of the auditory system?

Cochlea, cochlear nerve, or the cochlear nuclei

61

Patients with presbycusis have trouble hearing what types of sounds?

High-frequency sounds

62

Which cells of the vestibular system respond to angular acceleration and deceleration?

The hair cells of the three semicircular canals

63

What structures of the vestibular system respond to linear acceleration and deceleration?

The hair cells of the utricle

64

What type of cells are responsible for relaying vestibular stimuli from the hair cells to the vestibular nuclei?

Bipolar cells of the vestibular ganglion

65

What structures provide input to the vestibular nuclei?

Hair cells of the semicircular canal, hair cells of the utricle, and the flocculonodular lobe of the cerebellum

66

What structures receive signals from the vestibular nuclei?

The thalamus, spinal cord, cerebellum, and CNs III, IV, and VI