Lecture 6 - Cardiovascular Psychophysiology

Question 1

What things can we measure from the cardiovascular activity?

Answer 1

Physiology (ECG, MRI)
Sound (phonocardiography)
Electrical properties (ECG)
Blood flow (PPG, impedence cardiography)
Blood pressure ()

Question 2

What drives and regulates the cardiovascular state (3 things)?

Answer 2

1. Local reflexes
2. Sympathetic and parasympathetic activation
3. Psychophysiological effects

Question 3

Explain two cardiovascular reflexes from the heart/vessels, and two from in the tissue

Answer 3

Heart/vessels:

1. When more blood comes into the heart than goes out the cardiac output is increased
2. Pressure goes up in a larger blood vessel, then the vessel dilates

In the tissue:

1. Low oxygen in the tissue -> vasodilation
2. Longer-term; physiology may also change, for example; there are more blood vessels around a tumor

Question 4

Explain chronotopic control

Answer 4

Regulation of the heart rate
Intervals between contractions of the heart muscle

Parasympathetic system is mainly chronotopic control

Question 5

Explain inotropic control

Answer 5

Regulation of myocardial contractility (force contraction of the heart muscle)

The sympathetic system is mainly inotropic control and vasoconstriction/-dilation

Question 6

Explain the baroreceptor reflex

Answer 6

The baroreceptor reflex is;
When you stand up quickly, your blood pressure goes down. The body then reacts with parasympathetic deactivation and sympathetic activation

Question 7

Why does the baroreceptor reflex lead to a decrease in parasympathetic activity and an increase in sympathetic activity?

Answer 7

HR is connected to the sympathetic system. Needs to respond fast

Question 8

Explain respiratory sinus arrhythmia and the function of HRV

Answer 8

HRV is the variability between of interbeat intervals

Respiratory sinus arrhythmia

• Breathing in -> HR goes up
• Breathing out -> HR goes down
• Is parasympathetically controlled:
  
  • Parasympathetic system has a faster connection
  • Only the parasympathetic system creates high-frequency variations in HR

Question 9

What is the difference between SDNN and RMSSD?

Answer 9

SDNN looks at the standard deviation of the RR interval and only takes the average into account. Therefore you cannot see differences in IBI’s

RMSSD however looks at the difference between 2 IBI intervals. You thus need three IBIs to measure it. It detects whether differences between steps are becoming larger or smaller. This is therefore a good indicator for sinus arrhythmia

Question 10

What frequency component normally represents parasympathetic activation?

Answer 10

The high frequency component

Question 11

What does PEP stand for?

Answer 11

Pre ejection period

Question 12

Explain what PEP can show

Answer 12

PEP can see the time between the time when the ventricles start to contract and when blood starts flowing out of the aorta (pre-ejection period)

Low PEP is an indicator of high cardiac contractility (how forcefully the heart contracts) and therefore of high sympathetic activity

Question 13

Confounds can make it hard to interpret psychophysiological parameters when they: …..

Answer 13

1. Create physiological effects in the absence of a psychological event (false positive)
2. Mask an effect of a psychological event (false negative)