What does the biological approach focus on?
How biological factors, such as genes, impact on behaviour
What does the biological approach mainly use for their research?
Twin studies
What do twin studies show about behaviour in general?
Monozygotic twins (who share 100% of genotype) have a higher concordance rate with behaviour than dizygotic twins (who share 50% of genotype) showing the genetic component in behaviour
What are some issues with using twin studies?
- They are an unusual sample which makes it harder to generalise to non-twins
- It is hard to separate nature and nurture
- Never 100% concordance rate so other factors other than genetics must play a role
What type of studies are used by the biological approach psychologists? Why is this a strength?
Laboratory
Reliable
Control of variables
Scientific
What are two assumptions of the biological approach?
Everything psychological was at first biological
Evolution plays a significant role in psychology
What would the biological approach psychologists look at to further their understanding of psychology?
Chemistry of the body and biological structures
What does the biological approach fail to do?
Take into account the impact of the environment, surroundings and upbringing on everything psychological, meaning it is an incomplete explanation
What do the biological approach psychologists believe in terms of linking behaviour to evolution?
animals have adapted over time to suit their environment and link this back to changes in behaviours in humans
What is a significant limitation of the biological approach?
It is deterministic
Leaves little room for free will
Assumes the way we behave is already determined for us and we have very little impact on it
What are limitations of using lab studies?
Produce low ecological validity
Do the biological approach psychologists believe you can use animals to study human behaviour?
Yes
They believe that humans and animals share a lot of biological similarities
Outline Gottesman’s study into twins? (1991)
- Meta-analysis of 40 twin studies looking at schizophrenia
- Identical twins - 48% concordance rate
- Non-identical twins - 17% concordance rate
- Schizophrenia has a strong genetic basis
What are some evaluative points for Gottesman’s study?
- Carried out on field studies so it has high ecological validity
- The expected concordance for identical twins is 100% but this is not the case so other factors must be involved
- Hard to separate nature from nurture
What two types of studies are used to look at the influence of biology?
- Twin studies
- Adoption studies
Outline the methodology of Heston’s adoption study of schizophrenia. (1966)
- 47 adopted children whose biological mothers had schizophrenia were studied
- Control group of 50 adopted children whos biological mother’s didn’t suffer from schizophrenia
- Followed up as adults and were interviewed, given intelligence and personality tests
What were the results of Heston’s adoption study of schizophrenia (1966)
5 out of 47 became schizophrenic
4 out of 47 were considered borderline schizophrenic
0 in the control group became schizophrenic
Shows schizophrenia has a genetic basis
What are some evaluative points for Heston’s adoption study? (1966)
- Interview data can be unreliable and affected by social desirability
- But they are a good way to get naturalistic data
- Adopted children who’s mothers didn’t suffer might not have shown symptoms YET, cant rule it out
