4 - The Nature-Nurture Debate Flashcards
What does the nature-nurture debate question?
The extent to which our behaviour is a result of inherited characteristics vs acquired characteristics
Define ‘nature’?
The view that behaviour/psychological characteristics are determined by innate biological factors that are inherited at birth, such as genes + evolution
What type of people believe in the ‘nature’ debate?
‘Nativists’
What type of determinism is the ‘nature’ debate linked to?
Biological determinism
Define ‘nurture’?
The view that behaviour/psychological characteristics are acquired as a result of learning through experience + the environment
What type of people believe in the ‘nurture’ debate?
Environmentalists/empiricists
What type of determinism is the ‘nurture’ debate linked to?
Environmental determinism
What is influence from the environment?
Any influence on behaviour that is non-biological + non-genetic
What is a ‘tabula rasa’? Which side of the nature-nurture debate believes in it?
The concept that the mind is a blank slate at birth, which is gradually ‘filled’ as a result of experience
- Part of the nurture debate
Which psychological approach fits the ‘nature’ debate?
Biological approach
Which psychological approach fits the ‘nurture’ debate?
Behaviourist approach
What two levels of the environment did Lerner identify?
Pre-natal + Post-natal
Give a piece of evidence to support the ‘nature’ debate
Gottsman + Shields’ work on schizophrenia
- 1% population have it
- Meta-analysis of 40 family studies
- 46% chance of having it if both parents do
- Suggests genetic component
Give a piece of evidence to support the ‘nurture’ debate
Batson et Al’s work on schizophrenia
- Proposed ‘Double Bind Theory’
- Found link between schizophrenia + disordered communication within families
- Suggests environmental component
How can the nature-nurture influence on behaviour be measured?
Using a concordance rate (estimate about extent to which a trait is heritable + therefore due to nature)
- May be written as % or heritability co-efficient (0-1)
What does it mean if concordance rate for a trait is 1%?
Genes contribute almost nothing to individual differences
NURTURE more important
What does it mean if concordance rate for a trait is 100%?
Genes contribute completely/only reason for individual differences
(NATURE more important)
Give an example of a trait which has been analysed using concordance rates
IQ
- Concordance/heritability rate 50%/0.5
- IQ is half due to nurture + half due to nature
What is the interactionist approach to the nature-nurture debate?
A way of explaining the cause of behaviour in terms of a range of factors (nature + nurture) and how they work together
Rather than focusing on whether behaviour is caused by purely nature or nurture, what are psychologists now investigating?
Relative contribution of nature + nurture for each behaviour
Give an example of how an interactionist approach may be used to explain a behaviour
Attachment type
- Nature plays role (Kagan - child’s innate temperament)
- Nurture plays role (Bowlby - parental behaviour)
- Both factors contribute + impact each other
Define the diathesis-stress model + give an example
Suggests behaviour is caused by a biological vulnerability (diathesis) but needs an environmental trigger (stressor) to be expressed
E.g. PKU
- Genetic vulnerability from inheriting 2 recessive genes
- Environmental stressor is normal diet
- If given normal diet get disorder + get mental retardation
- Can be avoided if put on low protein diet for first 12yrs
Define epigentics + give an example
Interaction with the environment causes a change in genetic activity (but not change in genes themselves) as genes become ‘marked’ which determines if they are switched on or off
E.g. Dutch Hunger Winter
- Nazis blocked food supplies to Dutch
- Pregnant women had more low birthweight babies
- Babies twice as likely to develop schizophrenia
- Genes marked by environment (famine) affecting gene activity + behaviour of next generation
Define neuroplasticity + give an example
Interaction with the environment causes a change in the structure of the brain
E.g. London taxi driver experiment (Maguire)
- Driving a taxi in London (environment - nurture) increases hippocampus size over time (brain structure - nature)
What are the 4 evaluation points for the nature-nurture debate?
POS - Real world applications of the findings
POS - Adoption studies provide research to support the debate
NEG - Methodological issues with separating nature + nurture
NEG - Neg implications in believing extremely in either side
Explain the two positive evaluation points for the nature-nurture debate
Real world applications of the findings
- Understanding the relative contribution of nature/nurture as a cause can improve development of treatments for undesirable behaviours
- E.g. Nestadt found high heritability rate (0.76) for OCD. This encouraged early intervention for genetically vulnerable individuals so they are not exposed to stressors
- Debate has helped society by preventing + treating disorders
Adoption studies provide research to support the debate
- Adoption studies help separate causes of behaviour into nature or nurture, enabling the debate to continue
- If adopted children are more similar to biological parents (nature) or adoptive parents (nurture)
- E.g. Tienari found schizophrenia caused by both. Adopted ppts with schz mums studied against control group. Ppts with genetic vulnerability less likely to develop disorder if raised with a ‘healthy family’.
- Adoption studies allow debate to continue
Explain the two negative evaluation points for the nature-nurture debate
Methodological issues with separating nature + nurture
- Research into concordance rates etc may not be valid
- Too hard to distinguish between nature + nurture…
- > Nurture is pre-natal too (often confused with nature)
- > Nurture affects nature (neuroplasticity + epigenetics)
- > Nature affects nurture (Plomin’s “Niche Picking”)
Neg implications in believing extremely in either side
- Debate includes extreme beliefs which can be bad for society
- > Extreme nature - Can lead to eugenics, as believe this is only way to change behaviour, which can result in mass genocide to irradicate ‘undesirable traits’ from the gene pool (e.g. Nazis’ Holocaust)
- > Extreme nurture - Can lead to social control by extreme altering of environment to change ‘negative’ behaviours (e.g. in aversion therapy)
Define Plomin’s “Niche Picking”
The theory that individuals choose environment (nurture) to match their biology (nature)
- Example of nature affecting nurture
How are epigenetics + neuroplasticity different?
Epigenetics = gene activity changes due to influence of nurture (but genes stay same) Neuroplasticity = genes/biological structures change due to influence of nurture
Define eugenics
Selective breeding to irradicate ‘undesirable traits’
