Heart Activity and Behaviour

Question 1

Purely off its own accord, the SA node would set our heart rate at around ______, but vagus input sets it down more to ______.

Answer 1

120bpm

70-80

Question 2

The oft-cited normal resting heart rate is….

Answer 2

…. 72bpm.

Question 3

positive chronotropy is a fancy term for

Answer 3

increased heart rate.

Question 4

Principal CNS control comes from the _____.

Answer 4

Medulla.

Question 5

What other structures have been implicated in CNS HR control?

Answer 5

hypothalamus, amygdala, cerebellum

Question 6

Where do we find the baroreceptors in that eponymous reflex?

Answer 6

The CAROTID SINUS; responsible for the carotid sinus reflex.

Question 7

What’s the main point of the carotid sinus reflex?

Answer 7

Making sure the brain gets enough blood.

Question 8

Where do we find the cardiac acceleration centre?

Answer 8

The medulla.

Question 9

Low pressure in the carotid sinus activates the nerve signals to where? Leading to what?

Answer 9

Cardiac acceleration centre of the medulla; results in sympathetic drive (increased HR and BP).

Question 10

What valves are closing in the LUB sound? What’s this representing?

Answer 10

The closure of the atrioventricular valves in ventricular systole.
Just remember their in a lub-triangle (TRIcuspid valve closing the LUB sound).

Question 11

What is the P wave? What’s going on the the heart?

Answer 11

Represents propagation of SA signal.

In a ms time, atrial systole will take place.

Question 12

Which wave landmark represents ventricular depolarisation?

Answer 12

QRS complex.

Question 13

Which wave represents atrial repolarisation?

Answer 13

Trick question it doesn’t have one - it’s hiding behind the QRS complex.

Question 14

When in the ECG is ventricular contraction occurring?

Answer 14

Lumbers after the QRS complex (i.e. during but not neatly aligned with the ST interval).

Question 15

When does ventricular diastole occur in the ECG?

Answer 15

Immediately following the T wave.

Question 16

The PQ interval is around _____s

Answer 16

0.16s

Question 17

The QT interval is around _____s

Answer 17

0.30s

Question 18

The cardiac cycle is around ______s

Answer 18

0.83s

Question 19

Of the only ca. 800ms of the cardiac cycle, __________ takes up the majority, with about __________.

Answer 19

Diastole; 500ms.

The heart spends more time relaxing than contracting.

Question 20

What cardiac landmark do monitoring systems use to calculate HR?

Answer 20

R wave

“Rate” wave. Also like it’s the biggest one so makes sense.

Question 21

What are five things that impedance cardiography can measure?

Answer 21

Stroke Volume
Cardiac Output 
Ventricular Ejection Volume
Myocardial Contractility
Total Peripheral Resistance

Question 22

What nerve sense messages from the carotid sinus to the medulla?

Answer 22

The glossopharyngeal nerve (IX)

Question 23

HR might have an interesting relation to reaction time. What are three points that support this?

Answer 23

1. Fixed foreperiods gave HR deceleration.
2. Random foreperiods gave NO HR deceleration.
3. Magnitude of the effect dependent on cardiac cycle stage.

Question 24

HR could have an interesting relationship with motor performance. What are two points that are worth looking into?

Answer 24

1. HR during a motor performance activity exceeds metabolic demand; the emotional aspect probably makes the discrepancy (metabolic demand doesn’t account).
2. Studies in drivers shows that HR decreases as someone improves at a motor skill.

Question 25

What are some signs that HR is involved in verbal learning?

Answer 25

HR increases during the verbal acquisition phase of learning with habituation on repetition of the word/phrase.

Question 26

What learning-HR phenomenon sorta correlates to something you’ve seen to do with attention?

Answer 26

HR decreases during the mental intake of a problem, and increases during internal mental elaboration.

Question 27

What thing to do with HR and imagery is really easy to remember because it’s really unsurprising?

Answer 27

Emotionally charged imagery increases HR significantly compared to uncharged imagery.

The effect is exaggerated when the emotional content plays to personal significances.

Question 28

Cardiac acceleration/deceleration is associated with greater sensory acuity?

Answer 28

DECELERATION

Question 29

T/F degree of sensitivity to the environment can be predicted by HR?

Answer 29

True.

Question 30

HR response to a _____ goes down-up-down.

HR response to a _____ goes up-down.

Answer 30

tone

white noise

Question 31

HR increases with unfamiliar ones compared to familiar ones.

Answer 31

HR increases with unfamiliar ones compared to familiar ones.

Question 32

What was similar about RT and a stressor?

Answer 32

HR drop right before predicted stressor looks liked HR drop right before predicted RT signal.

Question 33

In those electro stress experiments, ________ were seen prior to stress onset but ________ were seen in the experimental session overall.

Answer 33

phasic decreases

tonic increases.