Additional Research Methods Flashcards
What are twin studies?
- A study which investigates nature and nurture by comparing identical and non-identical twins.
- Twin studies look for concordance between sets of MZ twins compared to sets of DZ twins for a certain behaviour.
What is the difference between Monozygotic (MZ) and Dizygotic (DZ) twins?
- MZ twins are identical twins and share 100% of their DNA.
- DZ twins are non-identical twins and share 50% of their DNA, like any other siblings.
What are concordance rates?
- The degree to which 2 people are similar on a particular trait.
- Represented by a correlation coefficient
Strengths of Twin Studies?
- Enables researchers to investigate the influence of genes, as it’s assumed twins share the same environments.
- Info for twin studies is often taken from twin registries –> Samples are large and representative.
Weaknesses of Twin Studies?
- Might overestimate genetic influence –> MZ twins much more likely to have similar environments than DZ twins.
- They provide a very broad indication that a behaviour has a genetic origin, but they cannot identify any specific genes involved.
What are adoption studies?
- Studies looking at children who’re adopted, and then comparing their characteristics with that of their biological and adoptive parents.
How are adoption studies usually measured?
- Using a correlational technique - Researcher is looking for a correlation between the behaviour of the children and their parents.
What are adoption studies typically looking for?
- Looking for characteristics they display.
- If the PP has characteristics of their natural parent, then they can be said to be genetic.
- If the PP has characteristics of their adopted parent, then they can be said to be environmental.
Strengths of Adoption Studies?
- Remove the extraneous variable of the environment –> Environment is not shared between the twins or their biology is not shared.
- Have been useful in showing that twin studies overestimate genetic factors. –> E.g., Eley et al. (1998) finding environmental factors more important, despite twin studies suggesting genetics are.
Weaknesses of Adoption Studies?
- Children may be adopted to families similar to their bio families, making environmental influences very similar.
- People who adopt are unusual - tend to be better educated, low rates of mental illness, higher socioeconomic groups etc. –> Not representative of the general population.
Why would we use animals in research?
- Have a simpler but SIMILAR CNS.
- It is possible to control environments where non-humans live.
- Researchers can conduct invasive procedures on non-humans, such as lesions.
- More ethical to test on animals than humans?
- Cheap & easy to repeat and handle
Animals (Scientific Procedures Act) 1986
- The Law governing the use of animals in scientific research.
- States researchers need a licence from the Home Office, premises MUST be licenced for animal research (and the researcher too), and lab animals must be from high quality suppliers who comply with the Home Office Standards.
What is a project licence?
- A licence specifying the species, number of animals and procedures that may be used.
- Only granted after considering the pros & cons of researching on the animals
What is a personal licence?
- A licence given to researchers after proper training courses are taken, providing they can perform the procedure.
- Holders must seek to minimise any suffering, pain, or distress
Arguments FOR animal research?
- Animals typically reproduce a lot quicker than humans –> E.g., Rats’ gestation periods are around 22 days –> Quicker to conduct research.
- High internal validity –> Can be no demand characteristics in animals.
- Animals share basic CNS structures to us –> Means that we’re able to generalise to some extent from animals to humans.
- Whilst unnecessary pain must be avoided, researchers can inflict pain on animals (unlike humans).
Arguments AGAINST animal research?
- Lacks EV –> Lab studies create behaviour that would NOT be natural for animals as they’re not in their natural habitat.
- Not really generalisable to humans –> We have higher brain functioning and more complex behaviours than animals.
- Can be argued that animals have the same rights as humans, and we have a moral obligation to protect them.
- Benefits of research are not known until AFTER the research, so the research may be for nothing.
What are case studies?
- An in-depth study over time, usually of an individual or a small group.
- Usually undertaken in a real life context.
Strengths of Case Studies
- Challenging existing theories
- Can be used to investigate instances of human behaviour and experiences that are rare or cannot be produced in a lab.
- Produces rich, in-depth data because the complex interaction of many factors can be studied –> Important for holistic psychologists.
Weaknesses of Case Studies
- Subjective - often based on interviews that are subject to researcher bias.
- Difficult to generalise from individual cases as each one has unique characteristics - E.g., Phineas Gage
- Often necessary to use recollection of past events as part of the case study - May be unreliable as people’s memories are inaccurate
- There are important ethical issues such as confidentiality and anonymity.
Who is the case study used for Cognitive Psychology?
- Henry Molaison (H.M)
Explain some basic facts about H.M
- Was an American memory disorder patient who was widely studied from 1957-2008.
- Suffered from epileptic seizures –> Surgery removed his Hippocampus to help –> Suffered memory loss as a side effect.
- Unable to learn new songs, faces, or make any new memories after the surgery.
- However, he began to learn new motor skills (like drawing a path through a maze) but didn’t remember that he’d done them.