Lecture 15 - Respiratory Control and Panic Disorder

Question 1

Is the respiratory system responsible for emesis (vomitting)?

Answer 1

Yes.

Question 2

What is the process called of gas exchange that occurs in the alveoli?

Answer 2

Diffusion.
Oxygen and CO2 exchange across the membrane of the alveoli.

Question 3

What is the trachea?

Answer 3

The air tube from mouth/nose to the lungss.

Question 4

What are the bronchi?

Answer 4

The trachea branches off into two tubes the bronchi, which in turn branch off another 24 times and end in alveoli (little air sacks with thin membranes surrounded by capillaries). This is what our lungs are made of.

Question 5

Is inspiration active or passive?

Is expiration active or passive?

Answer 5

Active.
The intercostal muscles and diaphragm actively engage to expand the lungs and create a vacuum that allows air into the lungs.

Passive.
The intercostal muscles and diaphragm relax to squeeze the air out of the lungs.

Question 6

What parts of the spine do the nerves responsible for inervating the intercostal muscles and diaphragm originate from?

Answer 6

The intercostal muscles are inervated by the intercostal nerves that originate from the thoracic spine.

The nerve responsible for inervating the diaphragm originates from the cervical spine. It is called the phrenic nerve.

Question 7

What is one of theories for why the nerve responsible for innervating the diaphragm (the phrenic nerve) extends from the cervical spine (which is so high up compared to the thoracic spine where the intercostal nerves extend from)
?

Answer 7

One theory suggests this was an evolutionary adaptation that ensured that this key muscle function was protected from spinal injury.

Question 8

The neurons that regulate and control the respiratory processes are located in the pons and medulla of the brain.

What group of neurons are responsible for regulating the rate of breathing?

Answer 8

The Pre Botzinger Complex. This is the pacemaker for respiration.

Question 9

What part of the brain is responsible for maintaining breathing whilst we are asleep?

Answer 9

The pre Botzinger complex.

Question 10

What part of the brain monitors and regulates breathing in response to CO2 levels?

Answer 10

The Retrotrapezoid Nucleus (RTN).

Question 11

What is the main function of the retrotrapezoid nucleus?

Answer 11

To monitor and regulate breathing in response to CO2 levels.

Question 12

What area of the brain registers lung irritants and stretch?

Answer 12

The Dorsal Respiratory Group (DRG).

Question 13

There are chemosensors in arteries that measures the pressure of oxygen and CO2 in the blood. Where do they send these signals?

Answer 13

To the RETROTRAPEZOID NUCLEUS (RTN).

Question 14

Where do the intercostal nerves originate from in the brain?

Answer 14

The VENTRAL RESPIRATORY GROUP.

Question 15

Where do the nerves that innervate the diaphragm (the phrenic nerve) originate and return to?

Answer 15

The DORSAL RESPIRATORY GROUP.

Question 16

Where do the nerves that innervate the abdominal muscles originate in the brain?

Answer 16

The VENTRAL RESPIRATORY GROUP.

Question 17

Are there connections between the amygdala and areas of the brain responsible for respiration, such as the PRG and DRG?

Answer 17

Yes.

Emotions have a strong influence on our breathing. Fear increases rate of breathing, whereas it is slow and deep when we are excited.

Question 18

Are panic attacks associated with hyperventillation (too much oxygen)?

Answer 18

Yes.

Question 19

Panic attacks are often associated with intense physiological symptoms, such as chest pain, dizziness, palpitations, sweatiness.

What is thought to cause this?

Answer 19

One of the key features of a panic attack is hyperventilation. This causes the level of CO2 in blood to drop. Lowered CO2 levels cause many of the same symptoms as those experienced during a panic attack.

Question 20

What are some of the respiratory abnormalities in panic disorder?

Answer 20

Increased CO2 sensitivity. This means that individuals are more sensitive to low levels of CO2. The body is more likely to sense that it is ‘suffocating’ and react accordingly at threshoolds of CO2 that are higher than the average person.

Increased sigh frequency, suggesting an attempt at releasing excess oxygen.

Question 21

What is the suffocation false-alarm hypothesis of panic attacks?

Answer 21

Suggests that the body responds to the decreased levels of CO2 as if it were suffocating. The symptoms associated with panic attacks are results of this response.

Question 22

Can toddlers get so upset that they end up holding their breath when they are crying so much, and they can pass out.

What does this tell us about emotions and breathing?

Answer 22

That emotions can strongly influence our respiration.