HEALTH
PSYCHOLOGY PART
2:
BIOPSYCHOLOGICAL
INTERACTIONS
PAULA PÉREZ ROMERO
KU LEUVEN 2022/2023
1
,LECTURE 1: Homeostatic Regulation
1. Introduction
Def: organism’s ability to keep its internal environment stable despite changes in the
external environment.
The central nervous system is the interface for interaction with external environment.
Stress is a danger to homeostasis. It has 2 parts
Stressor
Compensatory stress response
2 main types of stressor: Psychological and physical stressors.
To achieve homeostasis there are needed some mecanisims. The most important one
is Feedback Control:
➢ Temperature
➢ Blood Presure: the baroreceptors ca detext chages in arterial pressure and
the send signal to the medulla of the brain stemm which sends signals to
adjust the heart rate.
2
, ➢ Blood Ph/ PaCO2:
There’s another mecanism called feedforward control in which pertubations are
anticipated and corrected before they occur. Classical conditioning as a viable
mechanism. Example: Exercise Hyperpnea”:
- Increases in ventilation and heart rate occur
at the onset of physical exercise, even before
an increase in PaCO.
2. Hierarchy of Homeostatic Control:
➢ Organ level: intrinic control mechanisms
Organ adapts its functioning on its own in response to slow, local changes
Example: Frank Starling Mechanism
- If returning (venous) blood volume increases then atrium chambers fill more
before next beat.
- more effective filling of atria creates more wall stretch and more muscle.
fiber tension
- more vigorous contraction on next beat
- left ventricle empties more completely
- more effective blood flow into aorta
Σ Heart responses to flow demands caused by systemic circulation
➔ It is only possible when conditions are relatively stable
This mechanism doesn`t need our brain.
➢ Autonomic nervous system: it enervates the viscera, which is in our organ in
which we have limited awarness and voluntary control. One of the key
mecanism is the negative feedback
It has diferent pathways:
o Sensory pathwys (afferent)
o Motor pathways (efferent)
It has 2 divisions: symphathetic, parasympathetic. In most cases the have a
reciprocal regulation of organic function (if one goes down, the other one
goes up).
Each division of the ANS has:
o Sensory pathways from organs via ganglia to brainstem (afferent)
3
, o 4 response components:
(a) descending autonomic and pre-ganglionic fibers
(hypothalamus/brainstem intermediolateral cell column of spinal cord
(b) ganglion
(relay station for as-/descending signals, also part of local regulation
system/reflexes)
(c) postganglionic fibers
(messages more elaborated than in preganglionic fibers)
(d) neuroeffector junctions
(postganglionic fiber/receptor at target tissue, nerve impuls -> motor action)
Sympathetic division ANS
• 1:10 pre- vs postganglionic nerves which allows:
– General, broad influence on viscera
– Extensive linkages across widely distributed ganglia
– Closely integrated actions across different organs (‘in sympathy’)
• Neurotransmission:
– Acetylcholine (preganglionic)
– Norepinephrine (postganglionic): smooth muscle cells, cardiac
muscles and pace maker: activating function
Except: (a) sympathetic preganglionic nerves release acetylcholine at adrenal
medulla
-> release of catecholamines (Nor-/Epinephrine) into blood
(b) sympathetic nerves release acetylcholine at sweat glands (hands,
feet)
• More active during stress: crucial for Fight/flight responses.
Parasympathetic (vagal) division ANS
Ganglia more specific and nearer to target organ
• 1:3 pre- vs postganglionic nerves which lead to more localized, specific
actions directed at one organ
• Neurotransmission
– Acetylcholine preganglionic
– Acetylcholine (postganglionic): smooth muscle cells & cardiac muscle and
pace maker: inhibitory influence
• Less active during stress
• Supporting energy conservation, reproduction, digestion
4
PSYCHOLOGY PART
2:
BIOPSYCHOLOGICAL
INTERACTIONS
PAULA PÉREZ ROMERO
KU LEUVEN 2022/2023
1
,LECTURE 1: Homeostatic Regulation
1. Introduction
Def: organism’s ability to keep its internal environment stable despite changes in the
external environment.
The central nervous system is the interface for interaction with external environment.
Stress is a danger to homeostasis. It has 2 parts
Stressor
Compensatory stress response
2 main types of stressor: Psychological and physical stressors.
To achieve homeostasis there are needed some mecanisims. The most important one
is Feedback Control:
➢ Temperature
➢ Blood Presure: the baroreceptors ca detext chages in arterial pressure and
the send signal to the medulla of the brain stemm which sends signals to
adjust the heart rate.
2
, ➢ Blood Ph/ PaCO2:
There’s another mecanism called feedforward control in which pertubations are
anticipated and corrected before they occur. Classical conditioning as a viable
mechanism. Example: Exercise Hyperpnea”:
- Increases in ventilation and heart rate occur
at the onset of physical exercise, even before
an increase in PaCO.
2. Hierarchy of Homeostatic Control:
➢ Organ level: intrinic control mechanisms
Organ adapts its functioning on its own in response to slow, local changes
Example: Frank Starling Mechanism
- If returning (venous) blood volume increases then atrium chambers fill more
before next beat.
- more effective filling of atria creates more wall stretch and more muscle.
fiber tension
- more vigorous contraction on next beat
- left ventricle empties more completely
- more effective blood flow into aorta
Σ Heart responses to flow demands caused by systemic circulation
➔ It is only possible when conditions are relatively stable
This mechanism doesn`t need our brain.
➢ Autonomic nervous system: it enervates the viscera, which is in our organ in
which we have limited awarness and voluntary control. One of the key
mecanism is the negative feedback
It has diferent pathways:
o Sensory pathwys (afferent)
o Motor pathways (efferent)
It has 2 divisions: symphathetic, parasympathetic. In most cases the have a
reciprocal regulation of organic function (if one goes down, the other one
goes up).
Each division of the ANS has:
o Sensory pathways from organs via ganglia to brainstem (afferent)
3
, o 4 response components:
(a) descending autonomic and pre-ganglionic fibers
(hypothalamus/brainstem intermediolateral cell column of spinal cord
(b) ganglion
(relay station for as-/descending signals, also part of local regulation
system/reflexes)
(c) postganglionic fibers
(messages more elaborated than in preganglionic fibers)
(d) neuroeffector junctions
(postganglionic fiber/receptor at target tissue, nerve impuls -> motor action)
Sympathetic division ANS
• 1:10 pre- vs postganglionic nerves which allows:
– General, broad influence on viscera
– Extensive linkages across widely distributed ganglia
– Closely integrated actions across different organs (‘in sympathy’)
• Neurotransmission:
– Acetylcholine (preganglionic)
– Norepinephrine (postganglionic): smooth muscle cells, cardiac
muscles and pace maker: activating function
Except: (a) sympathetic preganglionic nerves release acetylcholine at adrenal
medulla
-> release of catecholamines (Nor-/Epinephrine) into blood
(b) sympathetic nerves release acetylcholine at sweat glands (hands,
feet)
• More active during stress: crucial for Fight/flight responses.
Parasympathetic (vagal) division ANS
Ganglia more specific and nearer to target organ
• 1:3 pre- vs postganglionic nerves which lead to more localized, specific
actions directed at one organ
• Neurotransmission
– Acetylcholine preganglionic
– Acetylcholine (postganglionic): smooth muscle cells & cardiac muscle and
pace maker: inhibitory influence
• Less active during stress
• Supporting energy conservation, reproduction, digestion
4
