NvN EVALs

• Nature vs Nurture Evaluation points:

  • S - supporting evidence for nature
  • S - supporting evidence for nurture
  • S - interactionist approach - interactionist ideas like epigenetics are supported by evidence
  • S - interactionist approach - supporting evidence
  • W - twin studies are correlational
  • W - animal studies - can't extrapolate
• S - nature - there are twin studies that show that the closer two individuals are genetically, the more likely that both of them will develop the same behaviour. For example, McGuffin conducted a twin study on depression and found concordance rates of 46% for MZ twins and 20% for DZ twins. As the proportion of shared genes increases ...
• (S - nature - twin studies)... As the proportion of shared genes increases when comparing DZ 50% to MZ 100%, we find that the likelihood of both twins sharing the trait of depression also increases. S bc this shows how characteristics/behaviour is determined by innate factors, thus showing that behaviour is linked to genes. Increases validity
• S - nurture - supporting evidence. Behaviourists assume that all behaviour can be explained in terms of experience alone. Pavlov and Skinner used concepts of classical and operant conditioning to explain learning. For example, behaviourists suggest that behaviours such as attachments could be explained in terms of classical conditioning. They argue that infants learn to associate the pleasure gained from food with a caregiver, leading to an attachment to them. Thus showing how the environment does have an influence on behaviour. Increase validity
• S - interactionist approach - ideas like epigenetics have supporting evidence. Dias and Ressler gave male lab mice electric shocks every time they were exposed to the smell of acetophenone, a chemical used in perfume. This led to the mice showing fear when they smelt the scent. It found that the mice's offspring and their offspring also feared the smell, even though they had not been exposed to the acetophenone before or received any shocks. S bc ...
• (S - interactionist approach - epigenetics)... S bc it shows that the environmental experience of the shocks led to leaving a "mark" on their genetic code. This mark led to the activation of certain genetic codes and a subsequent behavioural display of that code. This shows that behaviour is a product of both environmental and inherited factors. Increase validity
• S - interactionist approach - supporting evidence. There is also support for interactionist ideas like the diathesis-stress model. Tienari et al found that in a group of Finnish adoptees, those most likely to develop schizophrenia had both biological parents with a history of the disorder, so were vulnerable, and had "dysfunctional" relationships with their adoptive families (trigger). S bc ...
• (S - interactionist - supporting evidence)... S bc this shows that behaviour is in fact a result of both genetic and environmental factors. Thus showing that, in order to truly understand behaviour, one cannot solely focus on just the nature or nurture side. Increases validity