Stress in Health and Disease
Disclaimer: The lectures serve to support your learning and the reading of especially technical
materials, but do not follow the text as meticulously as first year’s lectures. You’ll see that less
and less, as your study progressed. Closely following the book is not recommended.
1) An Introduction to Stress
What is Stress?
Originally, the word “stress” was used in physics and mechanical engineering to indicate a state
of tension. Nowadays, stress is defined as “a mentally disruptive or disquieting influence” or
alternatively, “a state of tension or distress caused by such an influence.” In other words, stress
is being caused by stress. This is a circular definition and feeds into the lack of consensus on a
definition of stress. To shed some light on what stress is, we approach it in the following way:
We differentiate between stressor, stress perception, and stress response. This distinction is
somewhat artificial to make, although it helps in understanding how it works and in avoiding the
circular argumentation supported by the notion of “stress causes stress”.
Indeed, here stress is caused by a stressor. In turn, the perceived stress as a result of the stressor
leads to a stress response. The latter can be behavioral or physiological. He doesn’t want us to
use the word stress again: we talk about either “stressor”, “stress perception”, or “stress
response”.
I
,Stressors
e.g., job stress, family, relationships, caring for an ill loved one.
Measured through:
• Questionnaires (e.g., Life Events Questionnaire*, Daily Hassles**)
• Exposure Paradigms (e.g., lab-induced stress*** for public speaking with an audience or
attempting to solve impossible puzzles).
* Measures stressors (stress as a stimulus) by having people report the most stressful events of
their lives and rate them. However, this is difficult to quantify.
** More common measure of stressors. Because severe life events are very rare, investigating
the stress resulting from daily hassles may prove more fruitful. The idea is that these minor
stressors have a cumulative effect (when piled together, they amount to great stress). Indeed,
evidence supports the claim that micro-stressors are overall far more impactful than major life
events. Examples of this include stress due to work, family, caring for a sick loved one, social
relationships.
*** Stress can also be induced in the laboratory by means of some tasks, usually lasting anywhere
from 5 minutes to 2 hours. For instance, by asking people to improvise a speech (thereby inducing
anxiety about exposing oneself). The classic response that is recorded from such experiments
includes spikes in anxiety, heart rate, and adrenaline. Some of the complex tasks used for this
scope include mental arithmetic, improvised speech, intelligence tests. Some amplifying
components for such acute stressors are time pressure, social evaluation (e.g., presence of an
audience), motivation to avoid punishment / obtain reward.
A meta-analysis supported the reactivity hypothesis, that predicts exaggerated cardiovascular
responses to acute stress as being a risk factor for the development of cardiovascular disease.
Indeed, subjects who showed greater cardiovascular responses to lab-induced mental stress
were more likely to develop CVD compared to who did not. Also, stress responsivity seems to be
a trait. So, the way you respond cardiovascular-ly to daily hassles is predictive of CVD risk.
Although this is still a hypothesis, current evidence suggests it might be correct. More, there
seems to be individual response specificity: people show consistent response patterns and
magnitudes over time – which seems to result from both nature and nurture. Indeed, those who
showed a strong cardiovascular response at eighteen show a similar response at thirty-eight,
under the same circumstances.
II
,Stress Perception
Stress perception refers to stress as an evaluative process. This is illustrated in Lazarus and
Folkman’s model.
According to their model, a stimulus first
undergoes appraisal (primary and
secondary) and then, based on the
latter, the individual implements a
coping strategy.
Primary appraisal automatically and
unconsciously evaluates the stimulus as
good (benign) or bad (threatening).
Then, through secondary appraisal, the
individual assesses their resources and
chooses a coping method.
Appraisal of stressors is measured through:
• Perceived Stress Scale is about subjective appraisal of the stressor. Indeed, the scale
asks about one’s perceived “ability to handle”, “control”, or “coping”. Control seems to
be especially important for your perception of stress.
The importance of perceived control over the situation is illustrated in Brady’s experiment. He
found that, indeed, lack of control is a key determinant of stress. Or, in other words, stress is
mediated by perceived control.
In the experiment, two monkeys are placed in a cage, whose bars are electrically charge and shock the monkeys when they are
sitting. Both monkeys have a device. In the active condition, the monkey can turn the device on and off, thus controlling the
electrical shocks (both for itself and for the other monkey). In the joked condition (control) it can’t control the electrical shocks.
This is the only differing variable, as the two monkeys receive the same amount of electricity at the same time. Here, the monkeys
receive the same amount of stress (i.e., same stress exposure), but differ in stress perception: the joked monkey perceives more
stress due to the lack of control. As a result of this, the joked monkey develops all sorts of physical problems, unlike the other.
III
, Other than control, another key determinant of perceived stress is the social self. Indeed, as
states in the #social_self_preservation_theory, threats to one’s social self are incredibly potent
for stress. These result in (1) feelings of low social worth and (2) increases in cortisol. Such theory
holds for situations involving shame, embarrassment, or neglect. For instance, situations that
involve rejection or threaten one’s social standing (e.g., evaluative situations).
This was tested in the laboratory. Here, the objective stressor would be the same for everybody: talking about themselves. What
changed was the audience (being judgmental about them). Based on the condition, there would be either no audience, a one-
person audience, or a four-person audience. The manipulation of the social context is what makes this situation stressful, rather
than the task itself. The subjects in the four-person audience condition showed the strongest cortisol response.
Importantly, Cohen demonstrated that stress increases your vulnerability to infectious diseases:
Subjects were categorized based on the amount of stress on a scale from 3 to 12. Everyone was inoculated with the cold virus.
Depending on the variant, only 40% to 50% of those who are exposed get infected. With that in mind, in Cohen’s experiment
those with high levels of stress consistently showed the highest likelihood of becoming clinically ill, compared to the other
subjects. It is important to note that everybody was exposed to the same amount of virus, and everybody got infected. In other
words, all subjects – who had some degree of stress – got infected after exposure, but those with the highest level of stress most
often caught a cold.
Stress Response
e.g., anxiety, depression, burnout, physiological perturbations
We measure it in three ways:
• self-report (e.g., what you feel)
• behavior (e.g., showing anger)
• physiological measures (e.g., ANS)
Self-report (with all its limitations) and physiological measures
are the most used in psychology. The latter is more objective,
accurate, relevant, and there are multiple systems to tap into.
If self-report and physiology converge on a stress “diagnosis”, then you can make a case for the
vulnerability of the entire system, which in turn predicts a series of outcomes (e.g., poorer
vaccination response, slower wound healing). If biology is impacted as well, then you already
have something. Fascinating.
IV
Disclaimer: The lectures serve to support your learning and the reading of especially technical
materials, but do not follow the text as meticulously as first year’s lectures. You’ll see that less
and less, as your study progressed. Closely following the book is not recommended.
1) An Introduction to Stress
What is Stress?
Originally, the word “stress” was used in physics and mechanical engineering to indicate a state
of tension. Nowadays, stress is defined as “a mentally disruptive or disquieting influence” or
alternatively, “a state of tension or distress caused by such an influence.” In other words, stress
is being caused by stress. This is a circular definition and feeds into the lack of consensus on a
definition of stress. To shed some light on what stress is, we approach it in the following way:
We differentiate between stressor, stress perception, and stress response. This distinction is
somewhat artificial to make, although it helps in understanding how it works and in avoiding the
circular argumentation supported by the notion of “stress causes stress”.
Indeed, here stress is caused by a stressor. In turn, the perceived stress as a result of the stressor
leads to a stress response. The latter can be behavioral or physiological. He doesn’t want us to
use the word stress again: we talk about either “stressor”, “stress perception”, or “stress
response”.
I
,Stressors
e.g., job stress, family, relationships, caring for an ill loved one.
Measured through:
• Questionnaires (e.g., Life Events Questionnaire*, Daily Hassles**)
• Exposure Paradigms (e.g., lab-induced stress*** for public speaking with an audience or
attempting to solve impossible puzzles).
* Measures stressors (stress as a stimulus) by having people report the most stressful events of
their lives and rate them. However, this is difficult to quantify.
** More common measure of stressors. Because severe life events are very rare, investigating
the stress resulting from daily hassles may prove more fruitful. The idea is that these minor
stressors have a cumulative effect (when piled together, they amount to great stress). Indeed,
evidence supports the claim that micro-stressors are overall far more impactful than major life
events. Examples of this include stress due to work, family, caring for a sick loved one, social
relationships.
*** Stress can also be induced in the laboratory by means of some tasks, usually lasting anywhere
from 5 minutes to 2 hours. For instance, by asking people to improvise a speech (thereby inducing
anxiety about exposing oneself). The classic response that is recorded from such experiments
includes spikes in anxiety, heart rate, and adrenaline. Some of the complex tasks used for this
scope include mental arithmetic, improvised speech, intelligence tests. Some amplifying
components for such acute stressors are time pressure, social evaluation (e.g., presence of an
audience), motivation to avoid punishment / obtain reward.
A meta-analysis supported the reactivity hypothesis, that predicts exaggerated cardiovascular
responses to acute stress as being a risk factor for the development of cardiovascular disease.
Indeed, subjects who showed greater cardiovascular responses to lab-induced mental stress
were more likely to develop CVD compared to who did not. Also, stress responsivity seems to be
a trait. So, the way you respond cardiovascular-ly to daily hassles is predictive of CVD risk.
Although this is still a hypothesis, current evidence suggests it might be correct. More, there
seems to be individual response specificity: people show consistent response patterns and
magnitudes over time – which seems to result from both nature and nurture. Indeed, those who
showed a strong cardiovascular response at eighteen show a similar response at thirty-eight,
under the same circumstances.
II
,Stress Perception
Stress perception refers to stress as an evaluative process. This is illustrated in Lazarus and
Folkman’s model.
According to their model, a stimulus first
undergoes appraisal (primary and
secondary) and then, based on the
latter, the individual implements a
coping strategy.
Primary appraisal automatically and
unconsciously evaluates the stimulus as
good (benign) or bad (threatening).
Then, through secondary appraisal, the
individual assesses their resources and
chooses a coping method.
Appraisal of stressors is measured through:
• Perceived Stress Scale is about subjective appraisal of the stressor. Indeed, the scale
asks about one’s perceived “ability to handle”, “control”, or “coping”. Control seems to
be especially important for your perception of stress.
The importance of perceived control over the situation is illustrated in Brady’s experiment. He
found that, indeed, lack of control is a key determinant of stress. Or, in other words, stress is
mediated by perceived control.
In the experiment, two monkeys are placed in a cage, whose bars are electrically charge and shock the monkeys when they are
sitting. Both monkeys have a device. In the active condition, the monkey can turn the device on and off, thus controlling the
electrical shocks (both for itself and for the other monkey). In the joked condition (control) it can’t control the electrical shocks.
This is the only differing variable, as the two monkeys receive the same amount of electricity at the same time. Here, the monkeys
receive the same amount of stress (i.e., same stress exposure), but differ in stress perception: the joked monkey perceives more
stress due to the lack of control. As a result of this, the joked monkey develops all sorts of physical problems, unlike the other.
III
, Other than control, another key determinant of perceived stress is the social self. Indeed, as
states in the #social_self_preservation_theory, threats to one’s social self are incredibly potent
for stress. These result in (1) feelings of low social worth and (2) increases in cortisol. Such theory
holds for situations involving shame, embarrassment, or neglect. For instance, situations that
involve rejection or threaten one’s social standing (e.g., evaluative situations).
This was tested in the laboratory. Here, the objective stressor would be the same for everybody: talking about themselves. What
changed was the audience (being judgmental about them). Based on the condition, there would be either no audience, a one-
person audience, or a four-person audience. The manipulation of the social context is what makes this situation stressful, rather
than the task itself. The subjects in the four-person audience condition showed the strongest cortisol response.
Importantly, Cohen demonstrated that stress increases your vulnerability to infectious diseases:
Subjects were categorized based on the amount of stress on a scale from 3 to 12. Everyone was inoculated with the cold virus.
Depending on the variant, only 40% to 50% of those who are exposed get infected. With that in mind, in Cohen’s experiment
those with high levels of stress consistently showed the highest likelihood of becoming clinically ill, compared to the other
subjects. It is important to note that everybody was exposed to the same amount of virus, and everybody got infected. In other
words, all subjects – who had some degree of stress – got infected after exposure, but those with the highest level of stress most
often caught a cold.
Stress Response
e.g., anxiety, depression, burnout, physiological perturbations
We measure it in three ways:
• self-report (e.g., what you feel)
• behavior (e.g., showing anger)
• physiological measures (e.g., ANS)
Self-report (with all its limitations) and physiological measures
are the most used in psychology. The latter is more objective,
accurate, relevant, and there are multiple systems to tap into.
If self-report and physiology converge on a stress “diagnosis”, then you can make a case for the
vulnerability of the entire system, which in turn predicts a series of outcomes (e.g., poorer
vaccination response, slower wound healing). If biology is impacted as well, then you already
have something. Fascinating.
IV
