Nature-Nurture Flashcards
What is the nature side of the debate?
Behaviour has its roots in physiology. Those who stress nature reduce behaviour to biology, specifically the influence of genes, physical factors and what we are born with.
What is the nurture side of the debate?
Behaviour is largely driven by environmental influences. Those who stress nurture reduce behaviour to the social environment and claims we learn most of our behaviour from our environment, complete with its interactions.
What is the interactionist approach?
The true answer to the debate is that they both influence behaviour. They may suggest that key genes may give individuals predispositions to certain behaviours, however this is moderated by environmental forces.
What is heredity?
Refers to the genetic transmission of mental and physical characteristics from one generation to another.
What is environment?
Any influence on human behaviour that is non-genetic
What is the heritability coefficient?
A numerical figure ranging from 0 - 1.0 which indicates the extent to which the characteristic has a genetic basis - 1 means that it is entirely genetically determined.
What is the diathesis-stress model?
Suggests that both nature and nurture are critical for mental illness. Psychopathology is caused by a genetic vulnerability which is only expressed when coupled with an environmental trigger.
What is the heritability coefficient of twin studies?
Gottesman found that there was a 0.48 coefficient
Can nurture create diathesis?
Early experiences can become a diathesis rather than a trauma. Read in 2001 proposed the idea that early and severe child abuse can affect the developing brain
What is epigenetics?
Refers to a change in our genetic expression without changing our genetic code. It is a process that happens throughout life and is caused by interaction with the environment. Aspects of our environment and lifestyle leave epigenetic marks on our DNA which tell our bodies with genes to ignore and which to use. They may also influence the genetic code of our future generations so a third variable in the debate - the life experience of previous generations
What is an example of epigenetic inheritance?
Dias and Ressler trained mice to fear a chemical which had the scent of cherries and almonds by wafting it around a chamber whilst giving small electric shocks to the mice. This fear was passed to their offspring, as they shuddered at the presence of acetophenone. A third generation of mice also inherited this reaction, and they had olfactory neurons sensitive to this scent.
NATURE-NURTURE - There is evidence which shows that nature drives much of our behaviour
Nestadt found a concordance rate of o.68 for MZ twins but only 0.31 for DZ twins. This decrease in the rate of concordance makes sense as DZ twins only share 50% of their genetics. The higher genetic transmission in MZ twins makes sense.
NATURE-NURTURE - Nestadt evidence is flawed in support of nature
If OCD is completely genetic there should be a 100% concordance rate for MZ twins. This concordance rate is high but environmental influences must have had a part to play in modifying the likelihood. It does not provide a full explanation of why we acquire behaviour.
NATURE-NURTURE - There is evidence for an interactionist approach in explaining human behaviour
Tienaru studied a Finnish national sample of biological children of schizophrenic mothers who have been adopted - 5.8% developed SZ in a healthy environment and 36.8% developed SZ in a dysfunctional family environment. He suggested a biological diathesis.
NATURE-NURTURE - Debate has mass practical applications for society
By assuming parenting is learnt behaviour we could offer parenting classes to reduce poor relationships and hopefully the risk of developing SZ. We also assume that SZ had biological roots had led to medication like Clozapine that could target the release of dopamine levels.
