Neural control of breathing

Question 1

What is responsible for automatic breathing?

Answer 1

Respiratory pattern generators - oscilate 12x per min

Question 2

Inputs to respiratory pattern generators

Answer 2

paCO2
pH
paO2
(from chemoreceptors)

Lung stretch

Cerebral cortex - emotional states can affect breathing

Question 3

Output of RPG

Answer 3

Muscles of respiration

Question 4

Where is the RPG located?

Answer 4

Medulla

Question 5

Centres which RPG communicates and synapses with

Answer 5

Respiratory centre

Inspiratory centre

(each side of brain)

Question 6

Where does the inspiratory centre then synpase with?

Answer 6

Travels down spinal cord

Synapses with phrenic nerve which goes to diaphragm

and Intercostal nerve which goes to external intercostals

Question 7

What does expiratory centre synpase with?

Answer 7

Nerve travels down spinal cord

Synapses with intercostal nerve going to internal and innermost intercostal muscles

Question 8

Voluntary pathway for breathing

Answer 8

From cerebral cortex
Down and synapses with same cell bodies that RPG fibres synapse with to have effects on diaphragm and all intercostal muscles

Question 9

Which centre is mostly being stimulated at rest?

Answer 9

Inspiratory centre - expiration is passive at rest and only stimulated when exercising

Question 10

How does inspiration and expiration not occur at the same time?

Answer 10

Inhibit eachother - both cannot occur at once

Question 11

What is Ondines curse?

Answer 11

After stroke/brainstem injury, automatic pathway for breathing from RPG is destroyed.

Have to constantly THINK about breathing, must be ventilated when sleeping etc.