Brain Stem

Question 1

Brainstem = ?

Answer 1

Medulla + Pons + Midbrain

Question 2

On the dorsal side of the brainstem, what is the only exiting cranial nerve?

Answer 2

Trochlear nerve (CN IV)

Question 3

What is the blood supply of the brainstem

Answer 3

Vertebrobasiliar system

Question 4

What is the order in which cranial nerves enter into the brainstem (from midbrain to medulla)?

Answer 4

MB: 3, 4, (5)

Pons: 5, 6, 7, 8

Medulla: (5), (7), 9, 10, 11, 12

Question 5

What structures can you see in the rostral midbrain? (Name up to 8)

Answer 5

Superior colliculi, oculomotor nucleu, medial longitudinal fasciculus, red nucleus, substantia nigra, dentatothalamic tract (crossed), medial leminiscus, lateral spinaothalamic tract, crus cerebri (cerebral peduncle)

Question 6

Corticonuclear fibers project bilaterally to all motor cranaial nerve nuclei except …

Answer 6

The facial nucleus.

The division of the facial nerve nucelus that innervates the upper face receives bilateral corticonuclear input. The division of the facial nerve nucleus that innervates the lower face receives only contralateral corticonuclear input.

Question 7

What are the three nuclei associated with multiple nerves and what are those nerves?

Answer 7

Spinal trigeminal (5,7,9,10)

Solitary nucleus
(7,9,10)

Nucleus Ambiguus (9,10,11)

Question 8

Answer 8

Medullary Pyramidal Decussation

Question 9

Answer 9

Medullary Decussation