Biological Level of Analysis

1 - Patterns of behaviour can be inherited

• Principle inspired in Darwin's Theory of Evolution.
• Genetic information is transmitted from parents to child and over time charateristics and behaviours that are helpful to the individual or social group in terms of survival can be passed on.
• It is unlikely that one single gene is responsible for complex behaviours. (eg. schizophrenia, homosexuality, criminal behaviour...)
• Instead of a gene responsible for a behaviour psychologists suggest that there is a genetic predisposition for certain behaviours, but there needs to be an environmental trigger for that behaviour to arise.

2 - All observable behaviour (eg. emotions) can be traced to physiological events in the body. Called biological correlates of behaviour.

• Links found between psychological events and physiological activity (eg, neurotransmitters, hormones & brain localisation.)

3. Animal research can inform our understanding of human behaviour.

• Inspired by Darwin's theory of evolution.
• We share a common ancestor with animals, therefore we are similar in many ways.
• Valid to extrapolate animal behaviour to humans.
• Animal research is useful where the same research would not be possible on humans (due to ethical considerations).

Case Studies

• Researchers take advantage of naturally occurring irregularities (eg. brain damage or long term drug abuse)
• Useful source of information.
• Possible ethical considerations: Possible harm to participants due to lack of anonymity, participants might not be able to consent.
• Data gathered from these type of studies might not be applicable to the rest of the population ( Sample size really small.)
• Usually last for many years, therefore loads of data can be obtained. (in depht data).
• Not possible to establish cause and relationship.
• Examples of case studies; Phineas Cage, HM and Clive Wearing.

Correlations

• This method establishes a relationship between two variables. (eg. schizophrenia and genetic inheritance)
• There is no maipulation of an IV. Therefore there is no cause and effect.
• Genetic research is usually based on correlational studies. Twin studies are used to determine if behaviours are genetically based & inherited. In theory the higher the genetic similarty, the greater the likelihood of similar behavioural & psychological characteristics.
• In twin studies the correlation found is called the concordance rate.

Laboratory Experiments

• Used in order to establish cause and effect between variables.
• These can involve the use of animals or humans.
• Researchers want to test the effect of changes to physiology (eg. by an injection of hormones) or to test the effectiveness of a new medication (eg. for schizophrenia).
• With humans it is possible that the nature of the experiment will cause the person to change their behaviour. For example a placebo effect can occur when participants believe they are receiving a treatment - their body reacts to being treated rather than the specific treatment they receive.
• This is one of the most important arguments in favour of animal experiments; much biological research could not be done without animals.