Cranial Nerves I and II

Question 1

GVE is always…

Answer 1

parasympathetic

Question 2

Nucleus solitary tract is one of the exception to the 1 nuclei:1 function rule. What are its two functions?

Answer 2

Rostrally: SVA
Caudally: GVA

Question 3

What are the two nuclei for CN III?

Answer 3

• Edinger-Westphal nucleus: GVE, pupil constriction

- Oculomotor nucleus: GSE

Question 4

For sensation of the smal ear, what CN pull fibers from what nucleus?

Answer 4

CN VII, X
use
Spinal Nucleus of CN V located in the pons

Question 5

Nucleus ambiguus is used by what two cranial nerves?

Answer 5

CN IX and X

Question 6

Nucleus of solitary tract is used by what cranial nerves and what components?

Answer 6

Is used by CN VII, IX, X for SVA and GVA.

Question 7

SVA is for…

Answer 7

Smell and Taste:
using rostral part of nucleus of solitary tract

Smell = CN I
Taste = CN VII, IX, X

VII= ant 2/3 of tongue
IX= post 1/3 of tongue
X= epiglottis and glottis

Question 8

Medial Longitudinal Fasciculus (MLF)?

Answer 8

Found in the midbrain, used for turning the head and eye, in a coordinated fashion.

Question 9

Components of the mesencephalic nucleus of V.

Answer 9

GSA
Located: Pons, up into the midbrain
Mediates jaw-jerk reflex

• you have pseudopolar neurons, like those in the trigeminal ganglion, to relay the reflex. Relays to the motor nucleus to send the efferent fibers.

Question 10

Components of motor nucleus of V.

Answer 10

SVE
Loc: Pons
Muscles of mastication for V, tensor tympani, ant belly digastric and tensor veli palatini

Question 11

Components of chief/principal/main sensory nucleus

Answer 11

GSA
Loc: Pons
Relays information about the position, vibration and 2-point discrimination of the head and neck

like the nucleus of gracilis/cuneatus; dorsl column nuclei

located between the middle cerebellar peduncle and the pons

Question 12

Components of spinal nucleus of V

Answer 12

GSA
Loc: Pons down through medulla

V- uses it for pain and temperature sensation of head and neck

V, VII, IX, X - uses it for innervation of the ear pinna.

Like the nucleus proprious for spinalthalamic tract (pain and temp for body)

Question 13

Where do the trigeminalthalamic pathways synapse?

Answer 13

VPM (ventral posterior medial) Thalamus

Question 14

Trigeminal ganglion:

Answer 14

Semilunar or Gassarian, pesudounipolar cells conveying sensory info from the head

Question 15

What are the results of damage to CN VII on the facial muscles?

Answer 15

If you are damaging the corticobulbar tract/UMN: you will spare the upper face of the affected side because you facial neurons of the upper face receive bilateral corticobulbar input.
(suspect stroke with forehead sparing)

If you damage the lower motor neurons, you will have a facial droop/paralysis of the affected side because LMU receive unilateral corticobulbar input only on both the upper and lower face.
(suspect Bell’s palsy, something that affects the facial N, lower motor neuron)

Question 16

Wiping out nucleus solitarius tract could cause what types of problems?

Answer 16

Loss of taste (SVA), deep sensation to the oral cavity (GVA), and also BP issues with loss of sensation of carotid sinus (CN IX) and aortic baroreceptors (CN X).