4 - The Nature-Nurture Debate

Question 1

What does the nature-nurture debate question?

Answer 1

The extent to which our behaviour is a result of inherited characteristics vs acquired characteristics

Question 2

Define ‘nature’?

Answer 2

The view that behaviour/psychological characteristics are determined by innate biological factors that are inherited at birth, such as genes + evolution

Question 3

What type of people believe in the ‘nature’ debate?

Answer 3

‘Nativists’

Question 4

What type of determinism is the ‘nature’ debate linked to?

Answer 4

Biological determinism

Question 5

Define ‘nurture’?

Answer 5

The view that behaviour/psychological characteristics are acquired as a result of learning through experience + the environment

Question 6

What type of people believe in the ‘nurture’ debate?

Answer 6

Environmentalists/empiricists

Question 7

What type of determinism is the ‘nurture’ debate linked to?

Answer 7

Environmental determinism

Question 8

What is influence from the environment?

Answer 8

Any influence on behaviour that is non-biological + non-genetic

Question 9

What is a ‘tabula rasa’? Which side of the nature-nurture debate believes in it?

Answer 9

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

Question 10

Which psychological approach fits the ‘nature’ debate?

Answer 10

Biological approach

Question 11

Which psychological approach fits the ‘nurture’ debate?

Answer 11

Behaviourist approach

Question 12

What two levels of the environment did Lerner identify?

Answer 12

Pre-natal + Post-natal

Question 13

Give a piece of evidence to support the ‘nature’ debate

Answer 13

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

Question 14

Give a piece of evidence to support the ‘nurture’ debate

Answer 14

Batson et Al’s work on schizophrenia

• Proposed ‘Double Bind Theory’
• Found link between schizophrenia + disordered communication within families
• Suggests environmental component

Question 15

How can the nature-nurture influence on behaviour be measured?

Answer 15

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)

Question 16

What does it mean if concordance rate for a trait is 1%?

Answer 16

Genes contribute almost nothing to individual differences

NURTURE more important

Question 17

What does it mean if concordance rate for a trait is 100%?

Answer 17

Genes contribute completely/only reason for individual differences
(NATURE more important)

Question 18

Give an example of a trait which has been analysed using concordance rates

Answer 18

IQ

• Concordance/heritability rate 50%/0.5
• IQ is half due to nurture + half due to nature

Question 19

What is the interactionist approach to the nature-nurture debate?

Answer 19

A way of explaining the cause of behaviour in terms of a range of factors (nature + nurture) and how they work together

Question 20

Rather than focusing on whether behaviour is caused by purely nature or nurture, what are psychologists now investigating?

Answer 20

Relative contribution of nature + nurture for each behaviour

Question 21

Give an example of how an interactionist approach may be used to explain a behaviour

Answer 21

Attachment type

• Nature plays role (Kagan - child’s innate temperament)
• Nurture plays role (Bowlby - parental behaviour)
• Both factors contribute + impact each other

Question 22

Define the diathesis-stress model + give an example

Answer 22

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

Question 23

Define epigentics + give an example

Answer 23

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

Question 24

Define neuroplasticity + give an example

Answer 24

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)

Question 25

What are the 4 evaluation points for the nature-nurture debate?

Answer 25

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

Question 26

Explain the two positive evaluation points for the nature-nurture debate

Answer 26

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

Question 27

Explain the two negative evaluation points for the nature-nurture debate

Answer 27

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)

Question 28

Define Plomin’s “Niche Picking”

Answer 28

The theory that individuals choose environment (nurture) to match their biology (nature)
- Example of nature affecting nurture

Question 29

How are epigenetics + neuroplasticity different?

Answer 29

Epigenetics = gene activity changes due to influence of nurture (but genes stay same) 
Neuroplasticity = genes/biological structures change due to influence of nurture

Question 30

Define eugenics

Answer 30

Selective breeding to irradicate ‘undesirable traits’