What things make you stressed?
What does stress feel like?
What is stress?
Stress is the body’s response to situations that we feel may endanger us or our wellbeing. We feel stressed when the perceived demands of a situation are greater than our perceived ability to cope.
For example, taking an exam may not necessarily cause stress if we feel well prepared and able to cope. However, if we feel ill prepared, and we expect to do poorly, we are more likely to feel stress. But, for stress to occur there must be some negative consequence of failing the exam. If the exam holds no importance, the probability of feeling stressed is lower.
Selye’s experiments with rats (1939)
Hans Selye worked in a hospital, and began to notice that all patients, regardless of the cause of their illness shared a common set of symptoms, such as aches and pains, loss of appetite etc. He used his experience and experiments on rats to create his General Adaptation Theory
(GAS)
Take your rat ________________________ (name) and describe what you have to do to it.
Fill in the table below:
Time scale Rat’s reaction
Within 48 hours
Between 48 hours and 1 month
After 1-3 months

Listen to the other groups, and come to a logical conclusion for Selye’s experiments
Selye found that regardless of what caused the stress, if the threat persisted, the animal eventually died.
MAIN FEATURES OF THE GAS THEORY
The GAS describes what happens to the body when it encounters an unavoidable stressor. It suggests that the body will generally act in the same way regardless as to what is actually causing the stress; a non-specific response of the body to any demand made upon it. Selye proposed that there was one internal mechanism that produced the same generalised response. Selye identified 3 stages of the GAS.
Why is it called the General Adaptation Syndrome?

It’s general because the same response is produced regardless of the stressor

It’s adaptive because it’s the body’s way of adapting to and coping with a stressor

It’s a syndrome because the body produces a rage of responses, not just one
Stage 1: Alarm reaction
One of the sensory organs (such as ____________, ____________ or _______________) will send information to the hypothalamus in the brain. The brain interprets the stimuli as a threat, and activates the ____________________________________________________
(SNS). These are nerves that lie beyond the ______________________________________ of the brain and the spinal cord. This system causes changes in our bodies (see diagram on next page). As well as the nervous system, the endocrine system (________________) is activated. ____________________ is released from the adrenal glands causing changes similar to that of the SNS. During this stage, the body’s resistance drops as it tries to cope with the stressor. If the threat subsides, or the stressor is removed, the __________________________________________________(PNS) returns the body to its normal state. This stage is often referred to as fight or ______________________.
Watch the animation and label the picture with what physiological changes occur during the alarm stage.
(http://www.ngfl-cymru.org.uk/vtc/2008-09/psychology/ebook/Animeiddiadau/Saesneg/nervous_system/player.html)

What is the point of stress?
What purpose does the alarm reaction have? (Think evolution...)
Stage 2: Resistance
If the threat does not subside, or if the stressor is still present, the body needs to find a way to cope. The body is not physically able to maintain a high level of alertness indefinitely. Other hormones are released to raise the body’s resistance.
Match the hormone to what it does (pg 9)
Cortisol Keeps breathing and heart rate high
Aldosterone Keeps blood pressure high
Thyroxine Makes more energy available through the breakup of fat
During this stage, the initial symptoms of the alarm reaction subside, and the body appears to be coping. However, this state cannot last indefinitely. Eventually, the presence of these high levels of hormones has a negative effect on the body, and can lead to exhaustion.
Stage 3: Exhaustion
Eventually, there comes a point when the body is no longer able to cope with the stressor.
During the exhaustion phase:

The original signs of stress seen in the first stage return.

The body’s resistance rapidly declines.

The constant activity of the adrenal glands may result in permanent damage to them.

Stress related problems such as mental illness and cardiovascular disease may occur


The adrenal glands may be damaged from over activity
The immune system is left in a weakened state, as while the stress is occurring, normal functioning has slowed to cope.
What could happen to us if our immune system is not running at 100%
Complete the graph below to show how the body’s resistance changes during the three stages.
Level of normal resistance

Evidence for the GAS (pg 10)
What did De Groot (2002) find? How does this support the GAS?
Using the titles below, write a summary of Selye’s research on rats
Aim and context: (what was the aim of the research and what made him carry it out?)
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
Procedure: (What happened during the experiment?)
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
Findings: (What were his results?)
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
Conclusion: (What did he conclude about stress from his results?)
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
Going further...
 Read the blue box on page 11 about PTSD. How might this sort of prolonged stress cause physical problems according to the
GAS?

Does the theory take into account individual differences in how people cope with stress?
 Do you think that cognitive behavioural therapy or stress inoculation training may help overcome the negative effects of stress?

Subject your rat to extreme cold
Force your rat to do excessive muscular exercise
Cut the spinal cord of your rat
Inject your rat with a high dose of adrenaline
Immediately (within 48 hours)
An enlargement of the adrenal gland (which produces adrenaline), ulcers (open wounds) in the digestive system, shrinkage of the immune system
Immediately (within 48 hours)
An enlargement of the adrenal gland (which produces adrenaline), ulcers (open wounds) in the digestive system, shrinkage of the immune system
Immediately (within 48 hours)
An enlargement of the adrenal gland (which produces adrenaline), ulcers (open wounds) in the digestive system, shrinkage of the immune system
Immediately (within 48 hours)
An enlargement of the adrenal gland (which produces adrenaline), ulcers (open wounds) in the digestive system, shrinkage of the immune system
After a while (between 48 hours and a month)
The appearance and function of organs and the immune system returned to normal.
After a while (between 48 hours and a month)
The appearance and function of organs and the immune system returned to normal.
After a while (between 48 hours and a month)
The appearance and function of organs and the immune system returned to normal.
After a while (between 48 hours and a month)
The appearance and function of organs and the immune system returned to normal.
After a longer time (1-3 months)
The rats lost their resistance and showed the signs that they demonstrated in the first stage (enlargement of adrenal gland, ulcers and weakened immune system)
After a longer time (1-3 months)
The rats lost their resistance and showed the signs that they demonstrated in the first stage (enlargement of adrenal gland, ulcers and weakened immune system)
After a longer time (1-3 months)
The rats lost their resistance and showed the signs that they demonstrated in the first stage (enlargement of adrenal gland, ulcers and weakened immune system)
After a longer time (1-3 months)
The rats lost their resistance and showed the signs that they demonstrated in the first stage (enlargement of adrenal gland, ulcers and weakened immune system)