Stress Flashcards
What is stress:
- A state of physiological and/or psychological strain caused by anything (stressor) that tend to disturb the functioning of the body.
- A mismatch between the demands made upon an individual and their ability to meet these demands.
- Everyone reacts differently to stress, with some people having higher thresholds than others.
Positive of stress:
- Some can be productive, give you motivation and help you to perform better at something.
Cortisol:
- Hypothalamus and pituitary gland sense if your blood contains the right level of cortisol.
- The adrenal gland picks up signals on levels of cortisol in the blood stream.
- Constricts blood vessels and increases blood pressure to enhance the delivery of oxygenated blood.
- Advantageous for F or F response, but over time such arterial constriction and high blood pressure can lead to vessel damage and plaque build up, this can lead to cardiovascular disorders e.g: heart attack.
- Regulates body’s stress response.
- Helps control body’s us of fats, proteins, and carbs, or your metabolism.
- Increases the availability of blood glucose to the brain.
Newcomer et al:
- Found Ps given levels of cortisol high enough to produce blood sugar levels similar to those experiencing major stress events, were poorer at recalling prose passages compared to P’s given cortisol only high enough to produce a stress response similar to minor surgery (stitches out).
- Suggesting high levels do impact on cognitive functions.
General Adaptation Syndrome (GAS):
- Based on work with rats and later hospital patients.
- The rats in the research would become I’ll (eg. develop stomach ulcers) even when they were given harmless injections.
- From this Seyle concluded that rats became I’ll for the stress of the injections and that humans react the same way.
- Therefore, the body shows the same physiological response to all stressor and that non specidc response consists of three stages.
1st stage of GAS:
- Alarm reaction
- During the initial alarm stage, perceived threats trigger the hypothalamus to produce the corticotrophic releasing hormone (CRF).
- Which in turn stimulates the pituitary gland’s production of ACTH via the bloodstream which then acts on the adrenal cortex, which produces corticosteroids.
- Simultaneously the hypothalamus also activates the sympathetic branch of the ANS to stimulate the sympathetic branch of ANS to stimulate the production of adrenaline and noradrenaline from the adrenal medulla.
- As a results of these two parallel processes the body is activated in many ways and is prepared for F or F.
2nd stage of GAS:
- Resistance
- During the resistance stage, the body’s resources are fully mobilised to cope with the stressor.
3rd stage of GAS:
- Exhaustion
- If stressors persists and can’t be overcome, the resistance of the individual sooner or later gives way to exhaustion.
- The physiological consequences include effects on the adrenal glands, which are enlarged but depleted, and an endocrine system that is generally thrown into disarray.
- Seyley argued that all body tissues and processes can be affected and, in extreme cases, become diseased.
Evaluation of GAS model by Seyle:
- Highly scientific
- Rats were bred for scientific research, so they were used to the environment.
- GAS suggests a universal response to stress - ignores individual differences.
- Ulcers found in the stomach were thought to be due to stress, no direct link. They’re a results of bacteria in the stomach, if not treated can cause cancer - indirect relationship.
Immunosuppression:
The suppression of our immune system p, which protects us from antigens like bacteria, viruses.
Lymphocytes:
- Cells in the immune system
- They recognise and destroy harmful viruses and bacteria that invade the body.
- They lock onto the invaders, multiply rapidly and destroy them.
- 2 types
Types of lymphocytes:
- B cells: produce antibodies which are released into the fluid surrounding the body’s cells to destroy the invading viruses and bacteria.
- T cells: if the invader gets inside a cell, these lock on to the infected cell, multiply and destroy it.
Effect of cortisol on the thymus gland:
- Cortisol shrinks the thymus gland.
- Chronic stress produces excess cortisol which shrinks the thymus gland, and so less T cells are produced causing the immune system to be compromised = immunosuppression.
- There is a correlation, not causation.
Effects of stress on cardiovascular system:
- Raised blood pressure and increased heart rate can damage the blood vessels as the blood is being pumped faster and so at a higher pressure through the blood vessels.
- Blood vessels get built up with plaque.
- Stress activates the SNS leading to an increase in heart rate and BP.
- An increase in heart rate wears the blood vessels.
- Stress leads to increased glucose levels which can clump the blood vessels.
Williams et al (2000), method:
- Gave a questionnaire to 13,000 people where by none of them had a heart disease.
- The questionnaire contained a 10 question anger scale, for example if they felt like hitting someone when they got angry.
Williams et al (2000), results:
- After 6 years the health status of the P’s was checked.
- 256 had developed heart attacks.
- Those who had scored highly on the anger scale were two and ahold times more likely to have had a heart attack than those with low anger scores.
- People who scored moderately were 35% more likely to experience some forms of heart problems, compared to those with low anger anger scores.
Williams et al (2000), conclusion:
- The physiological response on stress is closely associated with cardio vascular disorders.
- It’s correlational evidence so causation can’t be assumed.
Williams et al (2000) aim:
To see if anger was linked to heart disease.
Wilbert - Lampen et al (2098), aim:
To investigate the effect if short term stress on CVD’s.
Wilbert - Lampen et al (2098), procedure:
Researchers looked at instances of nape art attacks in Germany during football matched played on the 1996 World Cup.
Wilbert - Lampen et al (2098), results:
When Germany played, there was a 2.66 increase in the number of cardiac emergencies on that day, compared with days when Germany were not playing.
Wilbert - Lampen et al (2098), conclusion:
Acute stress, such as watching your team play an important football match, doubled the risk of cardiovascular event.
Yusuf et al (2004), aim:
To investigate the effects of long term stress on CVD’s.
Wilbert - Lampen et al (2098), procedure:
P’s from 52 countries of different cultures were included 1500 people who had a heart attacked were compared with a similar number who had not.