Cranial Nerve Overview

Question 1

List the cranial nerves in order.

Answer 1

I- Olfactory
II- Optic
III- Occulomotor
IV- Trochlear 
V- Trigeminal
VI- Abducent
VII- Facial
VIII- Vestibulocochlear
IX - Glossopharyngeal
X- Vagus
XI- Accessory Nerve
XII- Hypoglossal

Question 2

The motor cell bodies of cranial nerves are located where?

Answer 2

Brainstem motor nuclei

Question 3

Which cranial nerves carry parasympathetic fibers?

Answer 3

3,7,9,10

Question 4

True/False: Cranial nerves form plexuses.

Answer 4

FALSE: Cranial nerves do not contribute to any plexus.

Question 5

True/False: Cranial nerves do not divide into dorsal/ventral primary rami.

Answer 5

TRUE

Question 6

Do sensory ganglia exist for cranial nerves? If so, give an example.

Answer 6

Yes, but they exist only for the spinal nerves that carry sensory fibers.

Ex: Trigeminal Ganglion

Question 7

Which cranial nerves are purely sensory?

Answer 7

I and II- Olfactory and Optic

Question 8

Name the cranial nerve associated with the Geniculate ganglia:

Answer 8

VII- facial

Question 9

Which cranial nerves carry sensory fibers?

Answer 9

5,7,8,9,10

Question 10

Spinal Nerves contain what types of fibers?

Answer 10

GSA, GSE, GVA, GVE

Question 11

Cranial Nerves carry what types of fibers?

Answer 11

GSA,GSE, GVA, GVE, SA (Special Sensory afferent)
and BE (Branchiomeric motor)

Question 12

True/False: No cranial nerve carries all 6 fiber types.

Answer 12

TRUE

Question 13

What sensations are SA fibers associated with?

Answer 13

Sensory info from specialized receptors in the head related to the special senses.

Question 14

What are the 5 special senses?

Answer 14

Sight, Hearing, Equilibrium, Taste, and Smell

Question 15

What do BE (branchiomeric Motor) neurons innervate?

Answer 15

Motor innervation to skeletal muscle in the head derived from branchial mesoderm.

Question 16

The skeletal muscle of the head is derived from what 2 mesoderm’s?

Answer 16

somatic mesoderm- muscles of the eye and tongue

pharyngeal arch mesoderm- all the other skeletal muscles in the head

Question 17

Name 4 non-brachiomeric muscles in the head/neck

Answer 17

Sternocleidomastoid, Trapezius, tongue muscles, and orbital muscles (eye)

Question 18

Where are the bodies of spinal GSA neurons located?

Answer 18

Dorsal root ganglia- pseudounipolar neurons

Question 19

Where are the bodies of spinal GSE neurons located?

Answer 19

Ventral horn of the spinal cord gray matter- multipolar

Question 20

WHere are the cell bodies of cranial GSA/SA neuronal fibers located?

Answer 20

Perioheral sensory ganglia - pseudounipolar

ex: trigeminal ganglia

Question 21

Where are the cell bodies of cranial GSE/BE neurons located?

Answer 21

Brainstem motor nuclei of the cranial nerves with motor function. - multipolar

Question 22

Preganglionic sympathetic fibers destined for the head arise from…? What is their anatomical trajectory?

Answer 22

Cell bodies lie in the Lateral horn gray matter of T1-T2 spinal segments. THe fibers exit the spinal cord via the T1, T2 spinal nerves to reach the sympathetic trunk. Run to the cervical chain ganglia. Synapse there with postganglionics. THe postganglionic fibers exit the cervival ganglia and form the CAROTID PERI-ARTERIAL PLEXUS.

Question 23

Do preganglionic sympathetic fibers run with cranial nerves?

Answer 23

NO! They run in the carotid peri-arterial plexus. They are of spinal cord origin, and the preganglionic fibers synapse with postganglionics within the cervical chain ganglia.

Question 24

What to the sympathetic fibers to the head target?

Answer 24

Sweat glands, dilator pupillae muscle, vascular smooth muscle

Question 25

CN III (occulomotor) is associated with which terminal ganglia? What fibers does it carry to this ganglion?

Answer 25

Carries presynaptic parasympathetic fibers to the Ciliary ganglion

Question 26

CN VII (Facial) is associated with what terminal motor ganglia?

Answer 26

Submandibular and pterygopalatime

Question 27

CN IX (Glossopharyngeal) is associated with what terminal motor ganglia?

Answer 27

Otic ganglion

Question 28

POSTganglionic parasympathetic nerve fibers follow the path of what to reach their targets?

Answer 28

The 3 branches of the trigeminal nerve (CN V): the Opthalmic, Maxillary, and Mandibular.

Question 29

Name the 3 cranial nerves with only sensory function~!

Answer 29

Optic, Olfactory, and Vestibulocochlear are all SPECIAL SENSORY NERVES

Question 30

Name the 5 cranial nerves with only motor function.

What fibers do they carry>

Answer 30

Occulomotor, Trochlear, Abducent, Accessory, and Hypoglossal

GSE fibers

Question 31

CN 3 (occulomotor) carries what 2 types of fibers?

Answer 31

GSE to skeletal muscles of the eye and GVE (parasympathetic) to the smooth muscles of the eyeball.