Human Diving Response (Phys Lab)

Front 1

What is the "official" physiology word for the cessation of breathing induced by diving?

Back 1

apnea

Front 2

Which is the nerve that reports sensations from the face that mediate the diving reflex?

Back 2

trigeminal, 5th cranial nerve

Front 3

Suppose that you or a classmate show a decreased magnitude of reading from the peripheral pulse monitor while holding your breath (like the figure hyperlinked to last week's cardio lab outline). This is most likely mediated by smooth muscle in what type of blood vessel?

Back 3

arteriole

Front 4

What is so unusual about the combination of pulse and pressure changes in diving?

Back 4

b.p. going up while pulse goes down -- these two would usually go up or down together

Front 5

Express MAP (mean arterial pressure) in terms of diastolic and systolic pressures.

Back 5

diastolic + 1/3(systolic-diastolic)

Front 6

Suppose the resting pulse is 72, typical for most people. You have a strip of 10 seconds from the power lab during a cold face dip where there are 6 heart beats. How was the pulse changed?

Back 6

([6beats/10s]x[60s/1min]=36beats/min, goes to half resting)

Front 7

If you used just a little too much low pass filtering on the EKG, which component(s) would be most inaccurately plotted out?

Back 7

the fast QRS components would be clipped

Front 8

What is the "official" physiology word for a low heart rate?

Back 8

bradycardia

Front 9

Why do you use one thumb for the pulse and the other arm for the pressure?

Back 9

(cuff closes off peripheral pulse)

Front 10

What does breathing through a snorkel without a face mask during a dive control for?
Two possible answers.

Back 10

(1) apnea (if you interpreted it as breathing vs. not breathing)

(2) trigeminal stimulation in eye-nose-area (if you interpreted it as with vs without a face
mask)

Front 11

What is so unusual about the combination of pulse and pressure changes in diving?

Back 11

b.p. going up while pulse goes down -- these two would usually go up or down together

Front 12

Why are pulse and blood pressure close to control levels during a dive with a face mask and a snorkel?

Back 12

face mask prevents trigeminal stimulation, snorkel avoids apnea

Front 13

What was the most convenient way to get an accurate measurement of the heart rate during the diving lab?

Back 13

use a snippit of the pulse monitor

Front 14

What happens to the heart rate of a rat trained to swim under water during that swim?

Back 14

goes way down

Front 15

The bradycardia of the diving response is mediated by what component of the autonomic nervous system?

Back 15

parasympathetic

Front 16

Give the name and the number of the cranial nerve for somatosensory input from the face.

Back 16

5 trigeminal

Front 17

Why did we provide a nose clip for the snorkel without the face mask?

Back 17

breathing by mouth under water

Front 18

Which cranial nerve (number) is the trigeminal nerve?

Back 18

5

Front 19

Which two systems are working in concert in the diving reflex that normally work in opposition?

Back 19

parasympathetic and sympathetic

Front 20

What is increased and what is decreased during a dive?

Back 20

blood pressure, pulse

Front 21

What does apnea mean?

Back 21

cessation of breathing

Front 22

Why could we do this lab by putting the face, and not the entire body, into water?

Back 22

mediated through trigeminal

Front 23

What two parameters were measured in the diving lab?

Back 23

blood pressure and heart rate

Front 24

Which artery is typically used to find blood pressure?

Back 24

brachial

Front 25

How is blood pressure increased during the diving reflex?

Back 25

sympathetic peripheral vasoconstriction

Front 26

Apnea is triggered by stimulation of what type of receptors on the trigeminal nerve?

Back 26

cold receptors

Front 27

How was the control taken in the lab? (what was done by the test subject?)

Back 27

breathed normally in air

Front 28

What part of the nervous system mediates the bradycardia of the diving response?

Back 28

parasympathetic

Front 29

What is the official word for the cuff you use to measure blood pressure from the brachial artery?

Back 29

sphygmomanometer

Front 30

What is bradycardia? How is bradycardia stimulated in humans?

Back 30

a condition where by blood vessels supply non-essential organs are constricted, redirecting blood to oxygen-requiring brain and heart

bradycardia is stimulated by holding breath and immersing face in cold water

Front 31

What is the name of nerve that mediates diving response in mammals?

Back 31

trigeminal

Front 32

What diving response occurs due to the stimulation of cold receptors in the nasal and pharyngeal passages?

Back 32

apnea

Front 33

What happens to heart rate (increase or decrease) when a subjectπs face is submerged in:

(a) cold water?

(b) room temperature water?

Back 33

(a) decrease

(b) decrease

Front 34

A subject first dives into cold water, then wears a mask and snorkel and dives in cold water. Is heart rate in the absence of the mask and snorkel lower or higher than heart rate in the presence of the diving apparel?

Back 34

Lower

Front 35

What cranial nerve is responsible for the diving response and where are its receptors located?

Back 35

Trigeminal nerve, cranial nerve 5
Face, nose, mouth, nasal and pharyngeal passages

Front 36

List two factors listed on the board which will diminish the diving response.

Back 36

Distracting subject and increasing fear of subject

Front 37

The diving reflex elicits what effect on heart rate?

Back 37

Decreased heart rate and CO – bradycardia

Front 38

What is the purpose of the diving response?

Back 38

Works to conserve blood and oxygen in the body. Shunts blood away from non-vital organs and to vital organs such as brain, heart, adrenal glands

Front 39

Why does the diving reflex cause vasoconstriction in some areas of the body and not others?

Back 39

Causes vasoconstriction in non-vital areas in order to maintain blood supply to vital organs such as the brain

Front 40

Remember the diving response lab? Why would a subject diving with a facemask show a higher heart rate than when diving without a face mask?

Back 40

The facemask did not allow cold water to reach the cold receptors and elicit the diving response which would cause a much more significant bradycardiac response than holding ones breath underwater while wearing a face mask

Front 41

What are the two distinct physiological changes that result from the diving response?

Back 41

Peripheral vasoconstriction and bradycardia (decreased heart rate)

Front 42

What is unique about the autonomic nervous system with respect to the human diving response?

Back 42

Usually, sympathetic and parasympathetic systems work against each other. But in the diving response, they work together to induce vasoconstriction and bradycardia.

Front 43

What was the purpose of performing a dive with the snorkel only and not the facemask?

Back 43

The snorkel tested the effects of only apnea to induce the diving response.