Issues and debates: the nature-nurture debate

Question 1

Define nature

Answer 1

refers to all of the genes and hereditary factors that influence who we are – from our physical appearance to our personality characteristics

Question 2

Define Nativism

Answer 2

the nature side of the debate- we are born this way

Question 3

Define Heredity

Answer 3

the genetic transmission of mental and physical characteristics from one generation to the other

Question 4

Define nurture

Answer 4

Refers to all the environmental variables that impact who we are, including our early childhood experiences, how we were raised, our social relationships, and our surrounding culture

Question 5

Define empiricism

Answer 5

the nurture side of the debate- we become that way through experience and environmental factors

Question 5

Describe nature

Answer 5

• Behaviour has its roots in physiology i.e. our genes and the functioning of our bodies (hormones, nervous system)
• Those who stress nature reduce behaviour to biology, specifically the influence of genes, physical factors and what we are born with

Question 6

Describe nurture

Answer 6

• Behaviour is largely driven by environmental influences i.e. our environment (learning, socialisation, social norms etc).
• Those who stress nurture reduce behaviour to the social environment and claim we learn most of our behaviour from our environment- complete with its interactions

Question 7

Describe the interactionist approach

Answer 7

• This suggests that the true answer to the nature –nurture debate, is that in reality both nature and nurture influence behaviour e.g. phenotypes
• They may suggest that key genes may give individuals genetic predispositions to certain behaviours e.g. potential; however this is moderated by environmental forces e.g. opportunities
• The best example of this comes from clinical psychology and the DIATHESIS-STRESS APPROACH

Question 8

Describe the ancient debate

Answer 8

The debate goes back a long way. Before the beginnings of modern Psychology there was a philosophical debate between the empiricists and the nativists.

The empiricists believed that the human infant is born with no knowledge or skills –John Locke’s view of the mind as a ‘tabula rasa’ or blank slate on which experiences are written. We acquire knowledge through experience and instruction.

The nativists believed that we are born with most of the qualities we will display as an adult – our character and predispositions are innate. Some philosophers such as Plato and Descartes suggested that certain things are inborn, or that they occur naturally regardless of environmental influences.

Question 9

Describe the heritability co-efficient

Answer 9

Heritability co- efficient is used to assess heritability (value of 0-10 -with 1 meaning entirely genetics determined behaviour)
e.g IQ is accepted to be 0.5 ( Plomin 1994) – suggesting both a genetic and environmental importance in IQ
It is hard to detangle NATURE AND NURTURE influences.
Many psychologists take an INTERACTIONIST APPROACH in this debate and will now ask what is the RELATIVE CONTRIBUTION of nature and nurture influences

Question 10

Use examples and the heritability coefficient to explain the interactionist approach

Answer 10

Models of mental illness which emphasises the interaction between nature and nurture tend to be most persuasive…

Diathesis – stress model suggests that both nature & Nurture are critical for mental illness e.g
This is a model suggests that psychopathology is caused by a biological/genetic vulnerability
(the diathesis) which is only expressed when coupled with an environmental ‘trigger’ (the stressor).

This is emphasised in Gotteman’s research that found from a family & twin study that MZ twins have a 0.48 heritability coefficient for SZ.

This suggests that genetics cannot be the only reason for the disorder as it would be a heritability co efficient of 1 if it was totally due to genetic heritability so there must be a relative contribution of nature AND nurture influences ( hence the interactionist view)

Question 11

Describe epigenetics in relation to the interactionist approach

Answer 11

This refers to a change in our genetic expression without changing our genetic code.
It is process that happened throughout life and is caused by INTERACTION with the environment.
Events we encounter (from smoking to pollution and war) leave epigenetic ‘marks’ on our DNA.
These ‘marks’ tell our bodies which genes to ignore and which to use and these may go on to influence the genetic codes of our children as well as their children!
Epigentics therefore introduces a 3rd element into the nature-nurture debate: the life experiences of previous generations.

Question 12

Epigenetics research Ressler and Dias (2014)

Answer 12

Lab mice trained to fear a chemical the scent of which has been compared to those of cherries and almonds.
Wafted the scent around a small chamber, while giving small electric shocks to male mice.
The mice eventually learned to associate the scent with pain, shuddering in the presence of acetophenone even without a shock.

This reaction was passed on to their pups. Despite never having encountered acetophenone in their lives, the offspring exhibited increased sensitivity when introduced to its smell, shuddering in its presence
A third generation of mice — the ‘grandchildren’ — also inherited this reaction, as did mice conceived through in vitro fertilization with sperm from males sensitized to acetophenone.

Pups and grandchildren even had more olfactory (sensory) neurons sensitive to this scent

Question 13

Evaluation point for nature-nurture debate: evidence

Answer 13

Point - There is evidence that shows nature drives much of our behaviour
Evidence - Nestadt’s (2010) review of twin studies found a concordance rate of 0.68 for MZ twins but only 0.31 (or 31%) for DZ twins in cases of OCD. This indicates that because MZ twins share 100% of their genetics but DZ only share 50% , there should be a higher rate of concordance in MZ twins if genes have a major part to play in passing on the disorder.
As 0.68 ( 68%) concordance in MZ twins is a higher genetic transmission than 0.31( 31 %) in DZ twins, this supports the claim.
Link back - This evidence implies genes must have a very significant part to play in the acquisition of behaviours as there is objective data to support this claim.

Question 14

Evaluation point for nature-nurture debate: flawed evidence

Answer 14

Point - However, this evidence is flawed in its support of nature
Evidence - For example if OCD was completely genetic there should be a 100 % concordance rate for OCD in MZ twins ie. if one MZ twin has OCD so should the other twin as they are genetically 100% identical.
Elaboration - This is however not the case, the concordance rate is very high in MZ twins but as indicated in Nestadt ‘s study, there was only 0.68 ( 68%) concordance but certainly not 100% . This means environmental influences must have had a part to play in order to modify the likelihood of one of the twin pairs getting OCD. This indicates for some MZ twins, the genetic predisposition for a disorder can actually be modified by the influence of nurture.
Link back - Hence, this evidence offers less than convincing support for nature arguments as they cannot provide the full picture about why we acquire behaviour.

Question 15

Evaluation point for nature-nurture debate:

Question 16

Evaluation point for nature-nurture debate: evidence for interactionist approach

Answer 16

Point - There is evidence for an interactionist approach in explaining human behaviour
Evidence - Tienari (2004) studied a Finnish national sample of biological children of schizophrenic mothers who had been adopted: 5.8% of the children developed SZ in a healthy family environment and 36.8% of the children developed SZ in a dysfunctional family environment.
Elaboration - Tienari suggests a biological diathesis (internal vulnerability) to schizophrenia triggered by a psychological stressor. In this case, it is the dysfunctional family environment because children in this environment were more likely to develop SZ than children who grew up in a healthy environment.
Link back - This suggests that fully understanding human behaviour may be best done by considering the impact of both nature and nurture on behaviour

Question 17

Evaluation point for nature-nurture debate: practical applications

Answer 17

Point -The nature-nurture debate could be said to have mass practical application for the benefit of society.
Evidence - For example, by assuming parenting is a learnt behaviour we could offer parenting classes to reduce poor communication and relationships in the household and hopefully minimise the risk of developing schizophrenia. Likewise, if we assume schizophrenia has biological roots e.g. high levels of dopamine we could suggest drug treatment such as anti-psychotic medication like Clozapine that would target the release of dopamine levels to help relieves symptoms of SZ
Elaboration - This implies both sides of the NATURE-NURTURE debate have far reaching implications that are useful to society. As a result, the intense debate could actually benefit our understanding of illnesses like schizophrenia which would lead to applications such as drug therapy.
Link back - This means people will have the advantage of being offered therapeutic measures that are psychological, if nurture is root cause and drug based therapy if nature is the root cause of the behaviour.

Question 18

Evaluation point for nature-nurture debate: combining the sides of the debate as benefits for society

Answer 18

Point - The debate has evolved in recent years, from one where nature or nurture were thought to affect behaviour, to one where both are assumed to affect behaviour, with the debate lying in how much each side affects behaviour.
Evidence - For example, schizophrenia is thought to be caused by biological and environmental factors. Biological causes include genetic vulnerability, neurochemical imbalance and neuroanatomical abnormalities which could interact with environmental factors including dyfunctional and poor quality family interactions and stress from life events such as daily stressors and life events.
Elaboration - Schizophrenic symptoms (hallucinations, delusions, and paranoia), can first be treated with biological drugs to combat these symptoms and then receive psychological treatment. Thus, the symptoms can be alleviated before the patient receives CBT, which provides them with the cognitive skills to change their maladaptive behaviours. Medication lowers dopamine levels and reducing positive and negatives symptoms, CBT then addresses the psychological aspects of SZ and helps patients develop coping strategies and process symptoms logically.
Link back - Therefore, the evolution of the debate may benefit society by combining both sides to produce effective treatments.

Question 19

Evaluation point for nature-nurture debate: nature is more scientific

Answer 19

It could be argued that the nature perspective is more scientific and observable than the nurture approach.
Comparison 1 - For example the nature ( Neurochemical ) explanation of SZ can be tested by using scientific equipment such as brain scans that give objective evidence, about changes in levels of DA in patient. This implies the DA account of schizophrenia promotes psychology as a rigorous scientific subject
Comparison 2 - However the nurture (operant conditioning ) explanation of maintaining phobias could be considered less scientific as other unseen factors that cannot be objectively measured may have a part to play in maintaining the phobia. As there are no scientific ways to measure such factors this does not promote psychology as a rigorous science.
Link back - Therefore the nature perspective may be the one that is most promoted in psychology to keep in line with other scientific disciplines.

Question 20

Evaluation point for nature-nurture debate: evidence that nurture is responsible for most our behaviour

Answer 20

There is evidence that shows nurture drives much of our behaviour
The nurture side of the debate can explain the development of behaviours such as phobias
For example Watson and Rayner conditioned Little Albert to have a phobia of white fluffy objects. This phobia was not present as a recorded behaviour before conditioning, therefore Watson and Raynor used only the S-R environment to produce this behaviour.
This evidence implies environment must have a very significant part to play in the acquisition of behaviours as there is objective measures used to support this claim.