nature vs nurture Flashcards
what is the nature-nurture debate?
concerned with the extent to which aspects of behaviour are a product of inherited or acquired characteristics (how much is each one)
what is heredity?
the genetic transmission of both mental and psychical characteristics from one generation to another
what is the environment?
any influence on human behaviour is non-genetic
what is the interactionalist approach?
a way to explain the development of behaviour in terms of a range of factors, including both biological and psychological ones. most importantly such factors don’t’ simply add together but combine in a way that can’t be predicted by each one separately I.e. they interact
what is the nature vs nurture debate really about?
its really about discussing how nature and nurture interact - an interactionist approach.
what is the diathesis-stress model?
it suggests behaviour is caused by a biological or environmental vulnerability (diathesis) which is only expressed when coupled with a biological or environmental ‘trigger” (stressor).
what are epigenetics?
Epigenetics refers to a change in our genetic activity without changing the genes themselves. It is a process that happens throughout life and is caused by interaction with the environment. Aspects of our lifestyle or events we encounter leave ‘marks’ on our DNA (genes), which switch genes on or off. This explains why factors have a lifelong influence even after you actually stop - they have changed the way your genes will be expressed.
what does epigenetics introduce to the debate?
epigenetic changes may go on and influence the genetic codes of our children, as well as their children. Epigenetics therefore introduces a third element into the nature-nurture debate - the life experience of previous generations.
what is nature?
refers to inherited influences, or heredity.
Rene Descartes (1596-1650) argued that all human characteristics - and even some aspects of knowledge - are innate. Psychological characteristics like intelligence or personality are determined by biological factors (genes), just as physical characteristics like eye colour or height are.
what is nurture?
refers to the influence of experience and the environment.
John Locke (1632-1704) argued that the mind is a blank slate at birth, which is then shaped by the environment.
Richard Lerner (1986) has identified different levels of the environment. This includes prenatal factors, such as how physical influences or psychological influences affect a foetus. More generally development is influenced postnatally in terms, for example, of the social conditions a child grows up in.
how do you measure nature & nurture?
The degree to which two people are similar on a particular trait can be represented by a correlation coefficient and is called concordance. Such concordance provides an estimate about the extent to which a trait is inherited - called heritability (the proportion of differences between individuals in a population, with regards to a particular trait, that is die to genetic variation)
what is the adoption studies strength?
-research into the nature-nurture debate is the use of adoption studies.
-Adoption studies are useful because they separate the competing influences of nature and nurture. If adopted children are found to be more similar to their adoptive parents, this suggests the environment is the bigger influence. Whereas, if adopted children are more similar to their biological parents (no influence on their environment), then genetic factors are presumed to dominate.
-A meta-analysis of adoption studies by Rhee and Waldman (2002) found that genetic influences accounted for 41% of the variance in aggression.
-This shows how research can separate the influences of nature and nurture.
what is the counterpoint to adoption studies?
-However, research suggests that this approach may be misguided, that nature and nurture are not two entities that can simply be pulled apart.
-According to Plomin (1994) people create their own ‘nurture’ by actively selecting environments that are appropriate for their nature. Thus, a naturally aggressive child is likely to feel more comfortable with children who show similar behaviours and will choose’ their environment accordingly. -Then, their chosen companions further influence their development. Plomin refers to this as niche-picking.
-This suggests that it does not make sense to look at evidence of either nature or nurture.
what is the epigenetics strength?
-support for epigenetics.
-One example of how environmental effects can span generations presumably through epigenetic effects comes from events of the Second World War. In 1944, the Nazis blocked the distribution of food to the Dutch people and 22,000 died of starvation, in what became called the Dutch Hunger Winter.
-Susser and Lin (1992) report that women who became pregnant during the famine went on to have low birth weight babies. Whilst this may be unsurprising, what is more interesting is that these babies were twice as likely to develop schizophrenia when they grew up compared to more typical population rates.
-This supports the view that the life experiences of previous generations can leave epigenetic ‘markers’ that influence the health of their offspring.
what is the real-world application strength?
-it has real-world application.
-Research suggests that OCD is a highly heritable mental disorder.
-For example Nestadt et al (2010) put the heritability rate at .76.
-Such understanding can inform genetic counselling because it is important to understand that high heritability does not mean it is inevitable that the individual will go on to develop the disorder.
-This means that people who have a high genetic risk of OCD because of their family background can receive advice about the likelihood of developing the disorder and how they might prevent this (e.g. learn to manage stress).
-This shows that the debate is not just a theoretical one but that it is important, at a practical level, to understand the interaction between nature and nurture.
