AS Module -PSYA2 Biological Psychology Stress. The Biological Approach Views psychology from the...

AS Module -PSYA2 Biological Psychology

Stress

The Biological Approach

• Views psychology from the physical perspective of the body

• Argues understanding physiological processes can help us see how our thinking, emotions and

behaviour are controlled.

Physiological processes = an explanation based on the biological (parts) or neurobiological (chemical factors) functioning of the body.

Biological Approach and Stress

• Unit will focus on:

• Biological events or processes that cause feelings and behaviours associated with stress.

• The negative consequences or stress.

• Biological factors that affect severity and response to stress.

• How biological factors interact with psychological ones.

• Clip – http://live.kerboodle.com

Lesson Objectives – Period1

By the end of the lesson you will be able to:

• Define the term stress AO1

• Describe and evaluate some of the methods used in measuring stress (Biological perspective) A02

• Identify the causes and effects of stress now and 200,000 years ago (Evolutionary perspective).

How would you define stress?

Is it the same for everyone?

Define the term stress AO1

• Stress is the biological and psychological responses experienced on encountering a threat that we feel we do not have the resources to deal with.

• (stimulus definition)

What is an example of a threat?

Feeling too hot?

Having a lot of work to do?

Being stuck in traffic? Are these always

stressful?

• Its important to note that Stress is the response to a threat we feel we cannot cope with.

• In some situations, feeling hot, having a lot of work to do or being stuck in traffic may not be stressful if we feel we are able to cope.

• However when they have the potential to elicit a stress response, they are known as Stressors

• Stressors = Internal or external factors that are threatening and have the potential to cause a stress response

Give an example of an internal and

external factor

Starter Task

• Now we have considered what stress is…..

• I would like you to think about your behaviour in the last few months and fill out the questionnaire.

• We will then work out your scores.

Female  Male  

Mean Score 

Mean Score 

Are there individual differences? Were more males more or less stressed than females?

Evaluation of questionnaire

• Is this a valid way of measuring stress?

• What are the flaws?• Subjective – open to interpretation• Time dependent• Requires honesty• Not actually measuring stress / stress response

• What could be an alternative methods?

Biological/physiological ways of measuring stress

• Blood pressure (BP) Inflated arm band• Breathing Tubes

around chest• Heart rate (HR)

Stress increase heart rate

ECG-electrocardiogram.

• Sweating - GSRHormone levelsBlood/urine

Stress increases BP, get blood pumping to muscles for energy and oxygen for F/F.

Stress increases breath rate, take in more oxygen for F/F.

Therefore heart rate increases to pump the oxygenated blood around the body.

Measure increased electrical activity in the heart.

Stressed Changes in GSR – sweat and electrical resistance of skin

Increases in adrenaline

Stress response and Evolutionary origins

• Evolution = process by which traits are shaped by natural selection.

• The stress response has been shaped by this process.

• Walter Cannon identified it as the ‘fight or flight response’, an animal that didn’t respond in this way is less likely to survive and reproduce.

• Biological processes of stress response would have prepared our ancestors by:

• Immediate changes – breathing faster, heart beating faster, pupils dilate (wider), increased muscle tension and greater strength.

• These changes are caused by the sympathetic pathway of the autonomic nervous system (sANS).

http://www.youtube.com/watch?v=sPS7GnromGo Stanford uni – psychological states, damage.

Modern Challenges• AS examinations• Uncertainty of new

relationships• The never-ending lack of

money

• Most modern day stressors are social and mental

• Is the fight or flight response suited to modern day living?

• Costs – uses calories, interferes with activities of finding food, forming alliances and mating.

• Chronic stress – weakens the bodies ability to defend itself to infection.

• But ancestrally the benefits outweighed the costs.

• Now = mainly costs.

• Chronic = persisting for a long time

Task

• Complete the table –

Causes of stress today

Causes of stress 200,000 years ago

Effects of stress on the body

GAS – Theory of stress response

1930’S Hans Selye Experimenting on rats – observed that the rats

showed distinctive physiological changes due to daily injections and other noxious agents (over a few months).

Changes included development of stomach ulcers (a stress symptom)

Selye reported the injections were harmless – thus the process was causing stress.

Conclusion: physiological reaction was due to the unpleasant stimulus

(stressor) and was causing

a stress response.

Changes, e.g. stomach ulcer, due to prolonged stressor in a situation of low control – does this occur in our society?

This is where stress is problematic and can lead to similar and worse physiological changes

Selye’s General Adaptation Syndrome –

universal response to stressors General: same response to all stimulus

Adaptation: because actually was an adaptive response

Syndrome: because there were several symptoms in the stress response.

3 Stage response:

Stage 1: Alarm = stress response – stressor has been detected and a response made to alarm. Adrenaline is produced leading to fight or flight activity.

Stage 2: Resistance = Apparent coping, if stress continues it is necessary to find some means of coping and resist collapse. In this stage the body is adapting to the demands of the environment, but at the same time resources are being used up. Thus = apparent coping because in reality things are deteriorating.

Stage 3: Exhaustion = breakdown, onset of stress-related illness. Eventually the body can no longer maintain normal functioning.

Initial physiological changes may appear, e.g. sweating, increased heart rate. The adrenal gland (produces adrenaline) may be damaged due to over activity and the immune system may unable to cope due to the production of proteins being needed elsewhere = ulcers, depression, cardiovascular problems etc.

Critique of GAS+ Influential on the

relationship between stress and illness.

+ Led to a vast amount of research.

+ Supports stress does affect body's systems and may lead to illness.

+/- focus on physiological factors as research on animals, humans have the ability to think and therefore can elicit more control over situations, e.g. driving test can practice relaxation techniques to reduce physiological activity.

- GAS does not include cognitive influences.

- Does not include individual differences

- Recent research has shown resources do not become depleted even under extreme stress – current view is exhaustion leads to increased cortisol that leads to stress related illness rather than deleted resources (Sheriden and Radmacher 1992).

Plenary• Stress is…………..

• A stressor is………. They can be ………. Or ………………. E.g. are ………………and……………..

• In response to stress the physiological changes are ………………

• We can measure stress by………………..

• Homework: Use the information sheets to fill out the boxes relating to Selyes General Adaptation Syndrome (1936).

Lesson Objective – P3

By the end of the lesson you will be able to:

• Research and present definitions of stress • Discuss Cox’s transactional definition of stress

• Improving independent enquiry and team work skills through research and presentation

In 3’s – 5 groups – upto 5 minutes.

Task – Research and present definitions of stress

• In 3’s research and present definitions of stress

• 20 minutes to research

and put the presentation together

• Presentation be upto 5 minutes – only has to be short.

• Must Include:

• Definition of stress• Physiological changes that occur

• Must also include:

• Biological reasons why this occurs (sj)

• Or• Theory or explanation e.g.• Evolutionary theory,• Hans Selyes response definition,

Response definition or Stimulus definition?

• What is an example for each?

• Do you think the stress response is either or?

• Cox developed the transactional model of stress…….

Cox’ s Transactional Definition of stress

• Cox (1975) = stress involves

external stimuli, the physiological response

to these stimuli, and psychological

processes that mediate between stimulus and response.

• The psychological processes

involve differences between individuals in their perception of the environmental demands and their own capacity to cope with them.

Therefore according to Cox, stress is the result of the perceived demands outweighing the perceived capability to cope

• This perception is influenced by a number of factors:

• personality, • situational demands, • previous experiences• any current stress state

already existing.

Critique in comparison to other definitions