Nature-nurture Debate Flashcards
Outline the nature-nurture debate
-concerned with extent to which aspects of behaviour are a product of inherited or acquired characteristics
Whats meant by nature ?
-refers to inherited influences or hereditary
-early nativists such as Descartes argued that all human characteristics are innate
-psychological characteristics like intelligence/personality are determined by biological factors just as physical characteristics like eye colour/height
Whats meant by nurture ?
-influence of experience and environment
-things other people teach them , things observed around them and different situations they’re in
-empiricists like philosopher John Locke argued the mind is a blank slate at birth , and is then shaped by the environment . This later became imp feature of behaviourist approach
-Lerner had identified diff levels of environment , includes prenatal factors, such as physical (smoking) and physiological (music) affect a feotus
-more generally development is influenced postnatally like the social conditions the child grows up in
How can you measure nature/nurture
-degree to which ppl are similar on a particular trait can be represented by correlation coefficient - concordance
-provides an estimate about extent to which a trait is inherited - heritability
-heritability is proportion of differences between individuals in popn with regards to a particular trait that’s due to genetic variation
-figure of 0.1 means genes contribute almost nothing to individual differences and 1.0 means genes are the only reason for individual differences
-general figure for heritability in IQ is about 0.5 which means half a persons intelligence is determined by genetic factors and other half must be environmental
Whats meant by heredity
-the genetic transmission of both mental and physical characteristics from 1 generation to another
Whats meant by environment
-any influence on human behaviour that is non-genetic
-may range from pre-natal influences in womb to cultural/historical influences at societal level
-includes biological influences eg the food you eat may affect mental development and physical growth
Whats meant by the interactionist approach
-nature-nurture debate seeks to answer the question whether behaviour is more influenced by nature/nurture
-its not really about one or the other because any characteristic arises from a combination of both - such as eye colour which is about .8 heritable
-Bowlby claimed that baby’s attachment type is determined by warmth and continuity of parental love (environmental)
-Kagan proposed a baby’s innate personality also affects the attachment relationship
-thus nature (child’s temperament) creates nurture in a sense (parents response ) so environment and heredity interact
Define the interactionist approach
A way to explain development of behaviour in terms of a range of factors including both biological and psychological ones
Importantly such factors dont simply add together but combine in a way that cant be predicted by each one separately ie they interact
Whats meant by the diathesis stress model
-suggest behaviour caused by biological / environmental vulnerability which is only expressed when coupled with biological/environmental trigger (stressor)
Whats an example of diathesis stress model
-explanations of OCD, a person who inherits a genetic vulnerability for OCD may not develop the disorder , but combined with a psychological trigger like a traumatic experience this may result in disorder appearing
What is meany by epigenetics
-refers to change in our genetic activity without changing genes themselves
-happens throughout life and is caused by interaction with the environment
-aspects of lifestyle or events we encounter - like smoking and diet to trauma and war , leave ‘marks’ on our DNA which switches genes on or off
-explains why factors like smoking have lifelong influence even after you stop as have changed gene expression
-changes may go on to influence genetic codes of our children and their children
- so a third element is introduced to nature-nurture debate - life experience of previous generations
Whats a strength of the nature-nurture debate to do with use of adoption studies
Adoption studies= useful as separate competing influences of nature and nurture
If adopted children found more similar to adoptive parents, suggests the environment is the bigger influence but if more similar to biological parents then genetic factors presumed domination
Meta analysis - adoption studies - by Rhee and Waldman found genetic influences accounted for 41% of radiance in aggression
Shows how research can separate influences of natural and nurture
What is counterpoint to a strength of nature-nurture debate and use of adoption studies
Research however suggests this approach may be misguided , that nature and nurture are not 2 entities that can be simply pulled apart
According to Polmin , people create own ‘nurture’ by actively selecting environments that = appropriate to their ‘nature’
A naturally aggressive child likely to feel more comfortable with children showing similar behaviour , so choose environment accordingly
Then chosen companions further influence their development , referred to as ‘niche-picking’
Suggests doesn’t make sense to look at evidence of nature/nurture
Whats another strength of the debate and its support for epigenetics
An example of how environmental effects can span generations presumably through epigenetic effects is events from WW2
In 1944 nazis blocked food distribution to Dutch people , 22,000 died of hunger - Dutch hunger winter
Susser and Lin report that women who got pregnant during the famine went on to have low birth weight babies, but these babies were also more likely to develop Sz when grown up compared to typical popn rates
Supports view that life experiences of previous generations can leave epigenetic ‘markers’ that influence health of offspring
Whats a further strength of the debate and its real-world application
Research suggests OCD is a highly heritable mental disorder
For eg Nestdat et al put heritability rate at 7.6
This understanding can inform genetic counselling as its important to understand high heritability doesn’t mean its inevitable the individual goes on to develop disorder
Means people who have high genetic risk of OCD due to background can receive advice about likelihood and prevention eg learning to manage stress
Shows the debate is not just theoretical as is also important practically to understand nature and nurture interaction
