Exam 3 - Cranial Nerves***MOST IMPORTANT***

Question 1

Each cranial nerve has a number indicating the order, from ____ to____, in which it arises from the brain

Answer 1

anterior to posterior

Question 2

Each has a name that designates the nerve’s ___

Answer 2

function

Question 3

Cranial nerves are functionally either sensory (afferent) neurons only, or mixed (some combination of afferent (sensory) and efferent (motor) neurons)

Answer 3

TRUE

Question 4

Those that are mixed may be primarily ___ or primarily ____

Answer 4

primarily motor OR primarily sensory

Question 5

Two cranial nerves contain only sensory neurons:

Answer 5

Cranial nerve I (olfactory)

Cranial nerve II (optic)

Question 6

One cranial nerve is so predominantly sensory that its motor function is frequently overlooked:

Answer 6

Cranial nerve VIII (vestibulocochlear)

Question 7

Cranial nerves I, II, and VIII are thus called…

Answer 7

sensory nerves (even though CN VIII is not exclusively sensory)

Question 8

Motor Cranial Nerves

There are no cranial nerves that are exclusively motor throughout their entire length, however ______ are commonly called motor nerves because their function is predominantly motor

Answer 8

cranial nerves III, IV, VI, XI, and XII

Question 9

They are often said to be “mixed, mainly motor” or “mixed, primarily motor” (as in the following slides)

Answer 9

Motor Cranial Nerves

Question 10

It is a general principle that the sensory function of such nerves is ______ of the muscles over which they exert motor control (the following slides assume that fact, and do not necessarily repeat proprioceptive functions)

Answer 10

proprioception

Question 11

Mixed cranial nerves

Cranial nerves ________ are termed mixed nerves because they have substantial motor and sensory functions, and contain axons of both sensory and motor neurons

Answer 11

Cranial nerves V, VII, IX, and X

Question 12

Single function motor cranial nerves

Most cranial nerves that have a motor function innervate more than one muscle, but the sole mission of two cranial nerves is to innervate a single muscle each:

Answer 12

Trochlear (IV) innervates the superior oblique

Abducens (VI) innervates the lateral rectus

Question 13

Trochlear (IV) innervates the superior oblique

Abducens (VI) innervates the lateral rectus

Answer 13

Both muscles are extrinsic muscles of the eye

Each nerve is primarily motor, with proprioception of its muscle being its sensory function

Question 14

No motor function nerves?

Answer 14

Cranial Nerve I and II

Olfactory and Optic

Question 15

Remember this cranial nerve is predominantly sensory, but DOES have a motor function

Answer 15

CN VIII

vestibulocochlear

Question 16

Somatic and autonomic

All motor cranial nerves have neurons that innervate ____ (skeletal) muscles

Answer 16

somatic

Question 17

Some motor cranial nerves also have autonomic motor axons:

Answer 17

III (oculomotor)
VII (facial)
IX (glossopharyngeal)
X (vagus)

Question 18

The autonomic axons are part of the parasympathetic division, and innervate….

Answer 18

glands, smooth muscle, and cardiac muscle

Question 19

Entirely sensory

Contains axons that conduct nerve impulses for the sense of smell (olfaction)

Olfactory bulb and olfactory tract are not CN I

Short function: smell

Answer 19

I – Olfactory

Question 20

Olfactory bulb and olfactory tract are NOT…

Answer 20

CN I

Question 21

CN I is sensory or motor?

Answer 21

sensory ENTIRELY

Question 22

Olfactory receptors are bipolar neurons:

Answer 22

CN I (olfactory)

Question 23

Bundles of axons of the receptors extend through the ____of the ____

Those bundles taken together are the ____

Answer 23

cribriform plate of the ethmoid

olfactory nerve

Question 24

Olfaction is assessed by having patient state whether or not they can perceive a common….

Answer 24

non-offensive smell such as soap, cloves, flavored Chapstick®, coffee, or vanilla

Question 25

Loss of the sense of smell is called...

Answer 25

anosmia

Question 26

Entirely sensory Contains myelinated axons that conduct nerve impulses for vision Optic nerve versus optic tract; optic chiasma Short function: vision

Answer 26

CN II - Optic

Question 27

Assessment of peripheral vision is one test associated with

Answer 27

cranial nerve II

Question 28

Mainly motor Controls extrinsic eye muscles not innervated by IV and VI Innervates intrinsic eye muscles: ciliary muscle (on lens) sphincter pupillae (iris) Short function: eye movement

Answer 28

III – Oculomotor

Question 29

Innervates intrinsic eye muscles: ciliary muscle (on lens) sphincter pupillae (iris)

Answer 29

III – Oculomotor

Question 30

III – Oculomotor Innervates intrinsic eye muscles:

Answer 30

ciliary muscle (on lens) sphincter pupillae (iris)

Question 31

Innervates most extrinsic eye muscles Parasympathetic innervation to intrinsic eye muscles Innervates levator palpebrae superioris (muscle of the upper eyelid)

Answer 31

III – Oculomotor

Question 32

Innervates most extrinsic eye muscles

Answer 32

III – Oculomotor

Question 33

III – Oculomotor Innervates...

Answer 33

Innervates levator palpebrae superioris (muscle of the upper eyelid)

Question 34

This is the pupillary light response test Both pupils should constrict when light is shined in only one eye

Answer 34

III – Oculomotor

Question 35

Mainly motor Smallest of the cranial nerves Innervates superior oblique muscle of the eye Only cranial nerve to arise from the posterior aspect of the brain stem Short function: eye movement

Answer 35

IV – Trochlear

Question 36

Smallest of the cranial nerves

Answer 36

IV – Trochlear

Question 37

Innervates superior oblique muscle of the eye

Answer 37

IV – Trochlear

Question 38

Only cranial nerve to arise from the posterior aspect of the brain stem

Answer 38

IV – Trochlear

Question 39

Short function: eye movement

Answer 39

IV – Trochlear

Question 40

IV – Trochlear The trochlea (trochle = pulley) is a pulleylike loop through which the tendon of the _____ muscle passes The superior oblique moves the eyeball...

Answer 40

The trochlea (trochle = pulley) is a pulleylike loop through which the tendon of the superior oblique muscle passes The superior oblique moves the eyeball inferiorly and laterally

Question 41

The superior oblique moves the eyeball

Answer 41

inferiorly and laterally

Question 42

The trochlea (trochle = pulley) is a pulleylike loop through which the tendon of the _____ muscle passes

Answer 42

superior oblique

Question 43

Following a moving object with the eyes assesses cranial nerves III, IV, and VI since all three innervate extrinsic muscles of the eye

Answer 43

IV – Trochlear

Question 44

Mixed Largest of the cranial nerves Emerges from pons isolated from other cranial nerves Provides sensory neurons to face, head, and anterior 2/3 tongue Motor neurons control chewing movements Short function: mastication, facial sensation

Answer 44

V – Trigeminal

Question 45

Short function: mastication, facial sensation

Answer 45

V – Trigeminal

Question 46

Provides sensory neurons to face, head, and anterior 2/3 tongue

Answer 46

V – Trigeminal

Question 47

Emerges from pons isolated from other cranial nerves

Answer 47

V – Trigeminal

Question 48

Largest of the cranial nerves

Answer 48

V – Trigeminal

Question 49

The trigeminal has two roots: smaller motor root supplying the muscles of ______ Larger sensory root, which has three branches: Ophthalmic nerve Maxillary nerve Mandibular nerve

Answer 49

mastication

Question 50

The trigeminal has two roots:

Answer 50

smaller motor root supplying the muscles of mastication Larger sensory root, which has three branches: Ophthalmic nerve Maxillary nerve Mandibular nerve

Question 51

V – Trigeminal Larger sensory root, which has three branches:

Answer 51

Ophthalmic nerve Maxillary nerve Mandibular nerve

Question 52

The trigeminal has two roots: smaller motor root supplying the muscles of mastication Larger sensory root, which has three branches:

Answer 52

``` Ophthalmic nerve (V1) Maxillary nerve (V2) Mandibular nerve (V3) ```

Question 53

TRIGEMINAL (V1) ? (V2) ? (V3) ?

Answer 53

Ophthalmic nerve Maxillary nerve Mandibular nerve

Question 54

.... anesthesia is a local anesthetic technique used by dentists and physicians.

Answer 54

Maxillary nerve

Question 55

An assessment of motor function is to have the patient bite down while feeling the ____ muscle, then to have the patient attempt to open their mouth against resistance applied by the examiner

Answer 55

masseter

Question 56

Trigeminal is NOT taste... it's tacticle

Answer 56

TRUE DAT

Question 57

An assessment of sensory function is to have the patient close their eyes, then the examiner touches the face with different objects (light pin touch, handle end of reflex hammer, Q-tip) and the patient describes the type of sensation as sharp, dull, soft, etc., the degree of pressure, and where it is on the face

Answer 57

NEAT

Question 58

The corneal reflex is a test for the ophthalmic nerve (CN V 1):

Answer 58

touching the cornea with a wisp of cotton evokes a reflexive blink.

Question 59

_____ is the dermatome for most of the skin of the face and scalp

Answer 59

Cranial nerve V

Question 60

Mainly motor Innervates lateral rectus muscle of the eye Nerve is also called the abducent Short function: eye movement

Answer 60

VI – Abducens

Question 61

The _____ muscle moves the eye laterally It causes ______, hence the name of the nerve that supplies it

Answer 61

lateral rectus abduction of the eye (movement away from the midline of the body)

Question 62

Following a moving object with the eyes assesses cranial nerves III, IV, and VI since all three innervate extrinsic muscles of the eye

Answer 62

VI – Abducens

Question 63

Mixed Somatic motor axons innervate muscles of facial expression, and stylohyoid, posterior belly of digastric, and stapedius muscles Parasympathetic axons extend to lacrimal glands, nasal glands, and saliva-producing sublingual and submandibular glands

Answer 63

VII – Facial

Question 64

VII – Facial Somatic motor axons innervate muscles of facial expression, and _____, posterior belly of, and _____ muscles

Answer 64

stylohyoid digastric stapedius

Question 65

VII – Facial Parasympathetic axons extend to lacrimal glands, nasal glands, and saliva-producing ____

Answer 65

sublingual and submandibular glands

Question 66

Sensory axons extend from taste buds in the anterior two-thirds of the tongue (the mobile tongue) Short function: facial expression, taste, salivation, lacrimation

Answer 66

VII – Facial

Question 67

Branches of the facial nerve:

Answer 67

``` Temporal Zygomatic Buccal Mandibular Cervical ```

Question 68

Having the patient exercise the muscles of facial expression by smiling, frowning and puffing both cheeks, and noting any asymmetries, drooping, sagging or smoothing of normal facial creases is an assessment of motor function

Answer 68

VII – Facial

Question 69

Mainly sensory Formerly known as the acoustic, or auditory nerve Vestibular branch carries impulses for equilibrium Cochlear branch carries impulses for hearing Short function: balance, hearing

Answer 69

VIII – Vestibulocochlear

Question 70

facial EXPRESSION

Answer 70

CN VII

Question 71

Formerly known as the acoustic, or auditory nerve

Answer 71

VIII – Vestibulocochlear

Question 72

Vestibular branch carries impulses for equilibrium

Answer 72

VIII – Vestibulocochlear

Question 73

Cochlear branch carries impulses for hearing

Answer 73

VIII – Vestibulocochlear

Question 74

Short function: balance, hearing

Answer 74

VIII – Vestibulocochlear

Question 75

TASTE BUDS ON WHICH NERVE

Answer 75

VII - FACIAL = TASTE on portion of tongue

Question 76

The examiner rubs fingers together both alternately and simultaneously very near to, yet not touching, each ear as one assessment of hearing

Answer 76

VIII – Vestibulocochlear

Question 77

Mixed Sensory axons to: posterior 1/3 of tongue for taste from taste buds, and for tactile sensation; baroreceptors in carotid sinus and chemoreceptors in carotid bodies Motor fibers to: parotid gland Short function: taste, salivation, innervation of pharynx

Answer 77

IX – Glossopharyngeal

Question 78

Sensory axons to: posterior 1/3 of tongue for taste from taste buds, and for tactile sensation; baroreceptors in carotid sinus and chemoreceptors in carotid bodies

Answer 78

IX – Glossopharyngeal

Question 79

Motor fibers to: parotid gland

Answer 79

IX – Glossopharyngeal

Question 80

Short function: taste, salivation, innervation of pharynx

Answer 80

IX – Glossopharyngeal

Question 81

The carotid sinus is a dilated region of the internal carotid artery. It contains the carotid body, which is a cluster of chemoreceptors that respond to changes in blood levels of oxygen, carbon dioxide, and hydrogen ions.

Answer 81

IX – Glossopharyngeal

Question 82

Having the patient open their mouth, protrude their tongue, and say “Ahh” while the examiner observes the soft palate, uvula, and pharynx, as well as listens to the voice for evidence of hoarseness, is an assessment of both cranial nerves IX and X

Answer 82

IX – Glossopharyngeal

Question 83

Mixed The longest cranial nerve Short function: swallowing, talking, cardiac, GI tract, respiration, taste

Answer 83

X – Vagus

Question 84

The longest cranial nerve

Answer 84

X – Vagus

Question 85

Short function: swallowing, talking, cardiac, GI tract, respiration, taste

Answer 85

X – Vagus

Question 86

____ is widely distributed in the head, neck, thorax, and abdomen

Answer 86

The vagus nerve X – Vagus

Question 87

Sensory function in taste, touch, pain, temperature, and proprioception from the epiglottis and pharynx; monitoring of blood pressure, oxygen, and carbon dioxide Somatic motor function in swallowing, coughing, and voice production Autonomic motor function (parasympathetic) in smooth muscle contraction and relaxation of GI tract, slowing of the heart rate, and secretion of digestive fluids

Answer 87

X – Vagus

Question 88

Sensory function in taste, touch, pain, temperature, and proprioception from the epiglottis and pharynx; monitoring of blood pressure, oxygen, and carbon dioxide

Answer 88

X – Vagus

Question 89

Somatic motor function in swallowing, coughing, and voice production

Answer 89

X – Vagus

Question 90

Autonomic motor function (parasympathetic) in smooth muscle contraction and relaxation of GI tract, slowing of the heart rate, and secretion of digestive fluids

Answer 90

X – Vagus

Question 91

Hyperactivity of the vagus nerves causes hypersecretion of acidic gastric fluids, which results in ulceration of the stomach wall. Patients with persistent and/or recurring ulcers can be treated with a selective vagotomy (partial severing of the right and left gastric nerves) to relieve this condition.

Answer 91

X – Vagus

Question 92

Ulcers may be treated with?

Answer 92

Vagotomy - CN X - Vagus

Question 93

Mixed Originates from both the brain stem and the spinal cord, so it is sometimes called the spinal accessory (only cranial nerve to have a spinal cord component) Impulses to voluntary muscles used in swallowing, and to trapezius and sternocleidomastoid Short function: pharynx & larynx muscles, neck & shoulder movement

Answer 93

XI – Accessory

Question 94

Originates from both the brain stem and the spinal cord, so it is sometimes called the spinal accessory (only cranial nerve to have a spinal cord component)

Answer 94

XI – Accessory

Question 95

Impulses to voluntary muscles used in swallowing, and to trapezius and sternocleidomastoid

Answer 95

XI – Accessory

Question 96

Short function: pharynx & larynx muscles, neck & shoulder movement

Answer 96

XI – Accessory

Question 97

Shrugging of the shoulders by the trapezius muscle against resistance from the examiner, as well as turning the head to the side, again against resistance

Answer 97

XI – Accessory

Question 98

Mixed Innervates all intrinsic muscles of the tongue as well as all extrinsic tongue muscles except the ______, for movements in speech and swallowing Short function: tongue movement

Answer 98

palatoglossus | XII – Hypoglossal

Question 99

(The palatoglossus is supplied by

Answer 99

CN X)

Question 100

Innervates all intrinsic muscles of the tongue as well as all extrinsic tongue muscles except the palatoglossus, for movements in speech and swallowing

Answer 100

XII – Hypoglossal

Question 101

Short function: tongue movement

Answer 101

XII – Hypoglossal

Question 102

Protrusion and side-to-side movement of the tongue is an assessment of the hypoglossal nerve

Answer 102

XII – Hypoglossal

Question 103

Balanced action of the paired genioglossi muscles is required to protrude the tongue straight out. If one genioglossus muscle is inactive, the action of the intact muscle is unopposed. The tongue then deviates toward the side of the inactive muscle

Answer 103

XII – Hypoglossal

Question 104

Genioglossus

Answer 104

XII – Hypoglossal

Question 105

taste posterior 1/3 of tongue

Answer 105

glossopharyngeal - IX

Question 106

Which two CN's deal with taste?

Answer 106

CN VII and CN IX CN VII - Facial - Anterior 2/3 tongue taste CN IX - Glossopharyngeal - Posterior 1/3 tongue taste

Question 107

Anterior 2/3 of tongue for taste

Answer 107

CN VII - Facial - anterior 2/3 tongue taste

Question 108

short function: taste, lacrimation, salivation + one more

Answer 108

facial muscle movement CN VII - facial

Question 109

Stylohoid Digastric Stapedius

Answer 109

Facial CN VII

Question 110

salivation of parotid gland

Answer 110

CN IX - glossopharyngeal

Question 111

swallowing, talking, cardiac, GI tract, respiration, taste

Answer 111

CN X - vagus

Question 112

speech and swallowing = which muscle and which CN?

Answer 112

palatoglossus - movements in speech and swallowing CN X - Vagus