Cranial And Spinal Nerves

Front 1

where spinal nerves exit spinal column

Back 1

intervertebral foramina

Front 2

What are the two roots of each spinal nerve?

Back 2

Dorsal (afferent, sensory) and Ventral (efferent, motor)

Front 3

Where are the unipolar neuron cell bodies of primary sensory afferent fibers located?

Back 3

Dorsal root ganglion

Front 4

Why are spinal nerves classified as Mixed nerves?

Back 4

they contain both motor and sensory fibers

Front 5

General Somatic Efferent (GSE): What are these and what do they innervate?

Back 5

Somatic motor functional component.

Innervates skeletal muscle.

Front 6

General Visceral Efferent (GVE): What are these and what do they innervate?

Back 6

Visceral motor functional component.

Innervates autonomic fibers to smooth and cardiac muscle.

Front 7

General Somatic Afferent (GSA): What are these and what do they innervate?

Back 7

General sensory functional component.

Receptors in skin and skeletal muscle sense Touch, pain, temp, pressure, vibration and proprioception sensation.

Front 8

General Visceral Afferent (GVA):What are these and what do they innervate?

Back 8

Visceral sensory functional component.

Carry info about pain in viscera from receptors in smooth muscle lining walls of organs and blood vessels.

Front 9

How is the development of somites tied with development of spinal nerves?

Back 9

Each spinal nerve innervates symmetrically paired somites. efferent fibers in a single dorsal root innervate cutaneous areas called dermatomes.

Front 10

Dermatome: defn

Back 10

A cutaneous region innervated by efferent fibers of a single dorsal root.

Front 11

Symptoms of unilateral lesion of spinal nerve

Back 11

Unilateral lesion:

ipsilateral: loss of discriminatory
touch, vibration & position sense,
Contralateral: loss of pain and temp

Front 12

Indicators of motor level lesions:
C3-5: what will be affected?

Back 12

Diaphragm

Front 13

Indicators of motor level lesions:
C5: what will be affected?

Back 13

Deltoid, biceps.

Loss of biceps reflex.

Front 14

Indicators of motor level lesions:
C7: what will be affected?

Back 14

Triceps, extension of wrist and fingers.

Loss of triceps reflex

Front 15

Indicators of motor level lesions:
C8: what will be affected?

Back 15

Interossei, abductor of fifth finger

Front 16

Indicators of motor level lesions:
L2-4: what will be affected?

Back 16

Quadriceps

Loss of knee jerk reflex

Front 17

Indicators of motor level lesions:
L5: what will be affected?

Back 17

Long extensor of great toe, anterior tibial

Front 18

Indicators of motor level lesions:
S1: what will be affected?

Back 18

Plantar flexors, gastroc m.

Loss of ankle jerk reflex

Front 19

What happens in the knee jerk reflex?

Back 19

It's a monosynaptic/two-neuron reflex.

The afferent (sensory) limb is a unipolar neuron in the dorsal root ganglion. The synapse is in the spinal cord. The motor/efferent limb is a motor anterior horn neuron innervating muscle fibers.

Front 20

How do interneurons play into multisynaptic reflexes (ie., flexor reflex)?

Back 20

They're in posterior horn or intermediate zone between the afferent and efferent neuron. They can provide inhibitory input to relax the opposing muscle group.

Front 21

Special Sensory Afferent (SSA):What are these and what do they innervate?

Back 21

They carry info from special sensory receptors: hearing, vision, vesitbular.

Front 22

Special visceral afferent (SVA): What are these and what do they innervate?

Back 22

They carry info from special sensory receptors for CHEMICAL SENSES.

Front 23

Special visceral efferent (SVE): What are these and what do they innervate?

Back 23

Similar to GSE except Innervate skeletal muscles derived from the branchial arches:
masticatory muscles (V),
muscles of facial expression (VII)
muscles of pharynx and larynx (IX and X)

Front 24

Skeletal muscles derived from branchial arches are innervated by______ while skeletal muscles derived from somites are innervated by__________

Back 24

SVE, GSE

Front 25

What do the sensory cranial nerves consist of? (except 1and2)

Back 25

Peripheral processes of primary sensory neurons located in sensory ganglia. Their central processes enter brainstem and terminate on brainstem afferent cranial nerve nuclei.

Front 26

What do the motor cranial nerves consist of?

Back 26

Axons that leave the motor neurons located in cranial motor nerve nuclei and travel to head musculature.

Front 27

What are the GVE components?

Back 27

Parasympathetic pathways that include 2 neurons:
1) Preganglionic: in a visceral motor nucleus

2) Postganglionic: in a distal ganglion

Front 28

Where are motor and sensory cranial nuclei located?

Back 28

Specific regions of brainstem

Front 29

what is the sulcus limitans?

Back 29

Located on dorsal brainstem surface, it demarcates the borderline between zone of efferent (motor) nuclei (medial, basal plate) and afferent (sensory) nuclei (lateral, alar plate)

Front 30

What is
A) Alar plate
B) Basal plate

Back 30

A) Zone of afferent sensory nuclei. Dorsal/alar. Moves laterally during development.

B) Zone of efferent motor nuclei that is ventral/basal. Moves medially during development.

Front 31

In brain stem, motor nuclei are found _________ while sensory nuclei are found __________.

Back 31

Medially; laterally

Front 32

What is the solitarius nucleus?

Back 32

Immediately lateral to sulcus limitans, a column of neurons receiving visceral afferent fibers. (GVA and SVA).

GVA fibers (general impulses from viscera) terminal in caudal portion; SVA fiber related to TASTE terminate in rostral portion. (associated with nervus intermedius CN VII, IX, and X)

Front 33

Some Say Marry Money, But My Brother Says Big Breasts Matter Most

Back 33

CN mneumonic for whether they carry Sensory (S), Motor (M), or Both (B)

Front 34

In addition to GSE component, what other component does CN III have?

Back 34

Has a GVE component carrying preganglionic parasympathetic nerve fibers from Edinger-Westphal nucleus to ciliary ganglion in eye

Front 35

What will damage to one of the CN XIs look like?

Back 35

Downward/lateral rotation of scapular and weakness in turning head ipsilaterally because of SCM

Front 36

What does CN XII innervate?

Back 36

Tongue muscles

Front 37

What does a lesion of (one of) CN XII look like?

Back 37

Atrophy of muscles on ipsilateral half of the tongue. Tongue deviates TOWARDS side of lesion due to unopposed action of genioglossus muscle on the normally innervated side of tongue.

Also fasciculations (tiny spontaneous contractions)

Front 38

What components does CN I innervate?

Back 38

PURELY sensory.

Special visceral afferent.

Front 39

What components does CN II innervate?

Back 39

PURELY sensory.

Special sensory afferent/SSA

Front 40

What components does CN VIII innervate?

Back 40

PURELY sensory.

Special sensory afferent/SSA

Front 41

Vision, hearing and balance are what functional component?

Back 41

Special sensory afferent (CN II and VIII)

Front 42

Olfaction and taste (chemical senses) are what functional component?

Back 42

Special visceral afferent (CN I, also all associated with taste CN VII, IX, and X)

Front 43

Skeletal muscle derived from the branchial arches are what functional component?

Back 43

Special visceral efferent (CN V (motor nucleus), CN VII (facial nucleus), CN IX (nucleus ambiguus - to stylopharyngeus), CN X (nucleus ambiguus - muscles to palate and pharynx and intrinsic larynx)

Front 44

What cranial nerves have GSE functional components?

Back 44

extraocular muscles and intrinsic muscles of tongue. (and trapezius and SCM)
CN III, IV, VI, XI, XII

Front 45

What are the CN V sensory nuclei?

Back 45

Chief sensory nucleus, spinal nucleus, mesencephalic nucleus

Front 46

What is the functional component of the chief sensory nucleus?

Back 46

Afferent fibers from all subdivisions of CN V (as well as VII, IX, X) terminate here and relay info about touch and pressure for face, mouth, and nose.

GSA.

Front 47

What is the functional component of the spinal nucleus of CN V? (also CN VII, IX, X)

Back 47

Perception of pain and temp.

GSA

Front 48

What is the functional component of the mesencephalic nucleus of CN V?

Back 48

Proprioception from teeth and palate area, stretch from muscles of mastication

Front 49

What is the functional component of the motor nucleus of CN V?

Back 49

SVE
Efferent to muscles of mastication

Front 50

What are symptoms of lesion of motor nucleus of CN V?

Back 50

Cerebellopontine angle syndrome

Front 51

What is trigeminal neuralgia?

Back 51

Brief, sharp pain of unknown etiology in face

Front 52

Lesions of CN VII result in :

Back 52

A) Atrophy of ipsilateral muscles of facial exprsesion

B) Hyperacusis (sounds painfully loud) because of paralysis of stapedius

Front 53

What are the functional components of facial nerve? (4)

Back 53

1) SVE: motor to muscles of facial expression

2) GVE: thru superior salivatory nucleus (pterygopalatine and submandibular ganglion) --> glands of nose, palate, tongue

3) SVA: Taste-ant 2/3 of tongue

4) GSA: Sensation to ext auditory meatus and posterior auricular area

Front 54

What do these symptoms indicate?

Paralysis and atrophy of m of mastication on side of lesion
Decreased strength of bite
Anesthesia to area of V3 distribution

Back 54

Motor lesion of CN V

Front 55

What is the afferent and efferent limbs of the Corneal blink reflex ?

Back 55

V1 – afferent limb
VII – efferent limb

Front 56

Any lesion that includes motor VII, and the region immediately medial to it, will result in:

Back 56

motor VII deficits PLUS
a lack of saliva secretion from the ipsilateral submandibular and sublingual glands,
and the loss of tearing from the ipsilateral lacrimal gland.

Front 57

Which CN carries info from carotid body chemoreceptors and carotid sinus baroreceptors?

Back 57

GVA (inferior petrosal ganglion) of CN IX

Front 58

What do these test for:
the patient's general sensation and
that of taste on the posterior third of
the tongue.
the gag reflex;

Back 58

CN IX

Front 59

Gag reflex
A) Afferent
B) Efferent

Back 59

A) CN IX
B) CN X

Front 60

A lesion in the medulla might affect both the n ambiguus and the inferior salivatory nucleus.

What symptoms will this cause?

Back 60

This will result in impaired swallowing and speech as well as the loss of salivation from the ipsilateral parotid gland

Front 61

Functional components of vagus nerve (5)

Back 61

1) GVE ; smooth muscle/glands of pharynx

2) SVE: Motor to muscles of palate and pharynx and intrinsic m of larynx

3) GSA : Sensation to skin of concha of ear

4) SVA: Taste buds in epiglottis region

5) GVA: Sensory to viscera

Front 62

What can injury to nucleus ambiguous result in?

Back 62

Paralysis of soft palate and failure of palate elevation. <b>Uvula tilts toward intact side.</b>

Impaired swallowing, hoarseness, loss of gag reflex

Front 63

Injury to the dorsal motor nucleus results in

Back 63

INCREASE in heart rate

Front 64

Which cranial nerves have a GVE (parasympathetic) component?

Back 64

III, VII, IX, X