nature vs nurture Flashcards
(8 cards)
1
Q
The nature-nurture debate
A
- the relative importance of heredity and environment in determining behaviour: the interactionist approach”.
2
Q
AO1
A
- The nature-nurture debate concerns whether traits are inherited or caused by environmental influences in upbringing and experience.
- Heredity concerns the genetic transmission of mental and physical characteristics from one generation to another.
- Heredity is assessed by calculating a heritability coefficient (twin studies are often used to calculate this- ALSO known as concordance rate)
- The coefficient ranges from 0 to 1 and tells us the extent to which genetics may have determined that behaviour
E.g. the heritability coefficient for IQ has consistently been found to be around 0.5 across multiple studies in many different cultures. - Environmental influences are slightly more difficult to sum up- but broadly we are talking about any mental or physical characteristic that was not written in an individual’s DNA (transferred genetically).
- This may range from pre-natal influences in the womb to cultural and historical influences on a societal level.
- On one side of the debate we have the “anatomy is destiny” standpoint where hard determinists believe that NATURE is entirely the cause of mental and physical characteristics.
- On the other side of the debate we have the view that we are born as a “tabula rasa” or blank slate and the possibilities for our mental and physical characteristics are endless and will be entirely determined by NURTURE (the opposite form of hard determinism).
- In the middle of the debate we have the INTERACTIONIST viewpoint which sees behaviour and traits as determined by a complex interaction BETWEEN genes and environment- both may be equally important in who and what we become.
- The Diathesis Stress model is often raised as a way of explaining behaviours- the idea that we are born with a biological predisposition towards certain traits and disorders- but these are mediated through our environment which may or may not bring these behaviours out.
3
Q
A03- EPIGENETICS
A
- In evaluation, we have a concept which crosses both sides of the debate.
- Epigenetics depends precisely on the interaction of both nature and nurture.
- This is where our genetic code can literally be altered by environmental influences, so that the genes we pass from generation to generation have been altered through each generation’s life experiences.
- What happens is that aspects of our lifestyle leave markers on our DNA which alter the genetic make-up we pass on to our children!
4
Q
Evidence for Epigenetics
A
- Ethically this is obviously impossible to test scientifically on humans, thus research is animal based.
- In 2014 researchers gave lab mice electric shocks every time they were exposed to a chemical in the scent of perfume (acetophenone). Their children went on to demonstrate exactly the same fear, without any prior conditioning or exposure.
- This is strong evidence for epigenetics, and suggests that the fear was passed down genetically because of changes to the parent’s DNA.
5
Q
Warrior gene
A
- Some researchers believe that interaction between genes and environment is what can bring out aggressive traits, rather than genes alone.
- i.e. the warrior gene needs to be coupled with some sort of childhood trauma or abuse to determine aggression. (diathesis stress model)
- In America in 2007, a man who had committed a violent murder and was facing the death penalty had his sentence reduced to manslaughter because the defence proved that he carried the warrior gene, and had a history of abuse.
- This case was revolutionary- never before had genetic evidence been used in the criminal justice system in this way.
- This has worrying implications for the future- if more evidence builds for genetic factors in aggression, will more violent criminals have their sentences altered. What about FREE WILL?!?
6
Q
interactionist - diathesis stress model support - Tienari schiz
A
- Investigated the interactionism of genetic vulnerability and parenting style
- Children adopted from 19,000 Finnish mothers with Sz between 1960 and 1979 were followed up. (longitudinal study)
- Adoptive parents were assessed for parenting style, and comparisons were made with a control group of adopted children WITHOUT genetic vulnerability
- Parenting style of high levels of criticism and conflict and low levels of empathy (i.e. Szg Mother) was found to be associated with Sz in the genetically vulnerable children ONLY. → they have the biology + stress → have the diathesis and stress
- This shows the importance of DIATHESIS and STRESS in the development of Sz- where stress in the form of poor parenting was not enough on its own to cause Sz
7
Q
Theories of attachment- Bowlby’s Monotropic Theory vs Learning Theory
A
- bowlby’s monotropic theory - nature, evolved, bio adaptations, survival
- learning theory - attachment via class + op conditioning
8
Q
ocd - nature vs nurture (diathesis stress model)
A
- If concordance rates are much higher in MZ twins, then this extra “likeness” should be due to genetics, because both MZ and DZ twins share the same environment.
- The higher the concordance rate in MZ compared to DZ twins, the stronger the evidence for Biology.
- There are many twin studies which have found support for the hypothesis that OCD is genetic
- a meta – analysis by Nestadt (2010) found 68% of MZ twins shared OCD compared to 31% DZ twins
- Furthermore, family studies have shown that people with a first degree relative with OCD have a 5 times greater chance of developing it themselves!
However…
- There are many issues with FAMILY studies- particularly pertinent is that it is very difficult to separate out the effects of nature (biology) and nurture (environment) when people grow up in the same home.
- They could just be copying each other or learning from one another.
- Concordance rates for twin studies are never conclusive- (never 100% vs 0%) so the DIATHESIS STRESS model could be the most VALID explanation.
