Brain Stem

Question 1

What are the 3 components of the brain stem

Answer 1

1. Medulla oblongata
2. Pons
3. Midbrain

Question 2

What is the medulla oblongata known as and what does it do

Answer 2

Known as the vital brain

Control involuntary actions of breathing, HR, BP, coughing, swallowing, vomiting, hiccupping, and sneezing

Question 3

True or False the spinal cord is a continuation of the medulla oblongata

Answer 3

True

Question 4

Name the 2 types of tracts of the white matter of the medulla oblongata

Answer 4

ascending (sensory) and descending (motor) tracts

Question 5

What are the pyramids of the medulla oblongata and why are the important

Answer 5

Bulges of white matter on the anterior of the medulla oblongata .

It is where the largest motor tracts pass from the cerebrum to the spinal cord

Question 6

Define decussation of the pyramids

Answer 6

axons of the pyramids cross to opposite sides

Question 7

What are the 7 medullary nuclei mention in the notes

Answer 7

1. Cardiovascular center
2. Cochlear nuclei
3. The deglutition center
4. The gustatory nucleus
5. Vestibular nuclei
6. Vomiting center
7. Medullary rhythmicity center

Question 8

What does the Cardiovascular center control

Answer 8

regulates blood vessel diameter and the rate and force of the heart

Question 9

What does the Cochlear nuclei control

Answer 9

receives auditory input from the cochlea

Question 10

What does the gustatory center control

Answer 10

receives input from the taste buds

Question 11

What does the deglutition center control

Answer 11

promotes swallowing of a food bolus

Question 12

What does the vestibular center control

Answer 12

equilibrium pathway from the vestibular apparatus of the inner ear

Question 13

What does the vomiting center control

Answer 13

area postrema, causes vomiting

Question 14

What does the medullary rhythmicity area control

Answer 14

basic rhythm of breathing

-divided in 2 clusters of neurons, the inspiration area and expiratory area

Question 15

What are the Olives

Answer 15

• oval shaped swellings lateral to each pyramid
• relays joint and muscle position impulses from the cerebral cortex, the red nucleus of the midbrain, and spinal cord to the cerebellum

Question 16

Where are the Pons located

Answer 16

anteriorly superior to medulla, and inferior to the midbrain

Question 17

What is the overall function of the pons

Answer 17

Acts as a bridge between one part of the brain to another

Question 18

Name the 2 bundles of axons located in the Pons

Answer 18

Lateral = connect the L and R side of the cerebellum

Vertical= consist of ascending (sensory) and descending (motor) tracts

Question 19

True or false certain pontine nuclei relay signals for voluntary movement from the cerebral cortex to the cerebellum

Answer 19

True

Question 20

Name the 2 nuclei in the pons that help control breathing and identify their fxn

Answer 20

Areas coordinate transition between inhalation and exhalation by regulating medullary rhythmicity centers

1. Apneustic area= prolongs inhalataion by sending stimulatory impluses to the inspiration area
2. The pnuemotaxic region =turns off inspiratory area before they become too full

Question 21

What is the midbrain also known as and what is it generalized function

Answer 21

• Mesencephalon

- Connects Pons to Diencephalon

Question 22

Describe the cerebral peduncles

Answer 22

area of the midbrain that conduct motor impulses from the cerebral cortex to the spine and conducts sensory impulses from the medulla to the thalamus

Question 23

What is the tectum

Answer 23

posterior area of the midbrain that contain the corpora quadrigemina (superior and inferior calliculli)

Question 24

What is the fxn of the superior callliculi

Answer 24

Reflex center for visual reflexes

• pupillary reflex
• accommodation reflex=adjusting lens
• involuntary turning of the head when an object is in the corner of your eye

Question 25

Explain the fxn of the inferior callliculi

Answer 25

Part of auditory pathway Responsible for STARTLE reflex=turning of your head to an unexpected noise

Question 26

What is the substantia nigra

Answer 26

- Darkly pigmented nuclei that release dopamine, that helps control subconscious muscle activities - loss of this is associated w/ parkinsons dz

Question 27

What are the red nuclei

Answer 27

-coordinate muscular movement (primarily large muscles of the shoulders and arms) --controls swing arms while walking and crowling of babies -axons from the cerebellum and cerebral cortex synapse with the red nuclei

Question 28

Describe the reticular formation

Answer 28

an extensive region of gray and white matter in the brain stem , comprised of ascending and descending neurons - main fxn is to regulate muscle tone - contains reticular activating system

Question 29

What is the fxn of the reticular activating system

Answer 29

sensory axons that help maintain consciousness and participate in awakening from sleep