Workshop 5: Brain stem

Question 1

The brainstem: 3 major parts

Answer 1

• midbrain
• pons
• medulla oblongata

(in evolutionary terms, the brainstem is the oldest part)

Question 2

What subdivision is the midbrain in?

Answer 2

Mesencephalon

Question 3

What subdivision is the pons in?

Answer 3

Metencephalon

Question 4

What subdivision is the medulla oblogata in?

Answer 4

Myelencephalon

Question 5

How many of 12 cranial nerves join the CNS at the brain stem?

Answer 5

10

Question 6

Midbrain (mesencephalon) (2 main parts)

Answer 6

• tectum
• tegmentum

Question 7

Mesencephalon: Tectum function

Answer 7

Dorsal part of mesencephalon

Auditory and visual system

Question 8

Mesencephalon: Tegmentum role

Answer 8

○ Rostral end of reticular formation

Sleep, arousal, muscle tone, movement & vital reflexes

Question 9

Reticular formation (net-like structure)

Answer 9

○ Interconnection of nuclei and neurones

	○ Runs through the core of the brain stem

	○ Receives and integrates input from all regions of the CNS

Only part of the brain essential to life!

Question 10

Metencephalon: Pons

Answer 10

• Latin for bridge
  
  • Connection between cerebrum & cerebellum
  • (Coordinates/ regulates movement)
  • Origin of 4 cranial nerves
    Core has a reticular formation

Question 11

Myelencephalon: Medulla oblongata

Answer 11

• “oblong marrow”
  
  • Most caudal (back) part of the brain stem
  • Terminal of the brain stem (connect to spinal cord)
  • Conduit of nerve tracts
  • Center for vital functions, e.g. heart rate, blood pressure & breathing
    Nuclei of the four inferior cranial nerves