The Nature-Nurture Debate

• The nature-nurture debate= a debate about whether variations in psychological & behavioural traits are caused by innate or environmental influences.
• Nature debate= the extent to which our genes & biology influence our characteristics & behaviours, ie what is inherited from our parents but not necessarily present at birth.
• Nurture debate= the extent to which our experiences influence our characteristics & abilities, ie what is acquired through interacting with our social & physical environment, even before we are born.
• Genetic Approach- nature side of debate:

  • Psychologists have used family, twin & adoption studies to demonstrate the influence of genetics on many characteristics by establishing concordance rates in individuals who are genetically similar.
  • Eg, in studies of bipolar disorder, a monozygotic concordance rate of 70% has been found compared to a dizygotic concordance rate of 23% (Kiaseppa, 2004).
• Evolutionary Approach- nature side of debate:

  • This approach asserts that behaviours beneficial to survival & reproduction will be naturally selected & so passed on to subsequent generations.
  • Bowlby (1969) proposed that the development of an attachment was adaptive as it meant the infant was more likely to be protected as well as learning relationship behaviours conductive to reproductive success.
  • So, should be universal across all cultures because we all evolved from the same group of early humans.
• Social Learning Theory- nurture side of debate:

  • Proposes that behaviour is acquired by learning from the observation & imitation of others.
  • Example: Akers (1998) found that the probability of engaging in criminal behaviour increases when one is exposed to models who commit crimes, particularly if we identify with those models & expect positive consequences for criminality.
• Social Psychology- nurture side of debate:

  • Social psychologists stress the importance of the interaction between individuals & their social context, ie how we are influenced by other people.
  • Batson et al (1956) developed the double-blind theory to explain the development of schizophrenia, where a person gets contradictory messages from their parents, eg mother tells son she loves him whilst turning her head away in disgust.
  • It is though that such conflicting messages prevent the child from developing a consistent construction of reality.
• • Nature- Interactionism- Nurture
  • Nature: behaviour is a product of innate influences.
  • Interactionism: nobody truly thinks behaviour is a product of one or the other & the distinction is outdated. It is widely acknowledged that completely interdependent in terms of determining behaviour is known as the Interactionist Approach.
  • Nurture: behaviour is a product of environmental influences.
  • Any 'debate' is really about how the interaction occurs or whether one side or the other has dominance in terms of determining a characteristic.
• Interactionist Approach:

  • Chomsky Language Acquisition Device- the ability to learn any language.
  • It makes evolutionary sense that we inherit the systems required for language (it has been crucial for our species).
  • However, language does not develop without input from the environment, which allows for flexibility, eg we learn the language we are exposed to.
• Evaluation of the nature-nurture debate- :/:

  • The Diathesis-Stress Model aims to show the interaction between genes & the environment- involves a person being born with a diathesis (a biological predisposition), but this is only expressed under the right environmental conditions.
  • For example, twins studies indicate a large genetic influence on the development of schizophrenia (around 50%).
  • A person may be born with a vulnerability towards developing the disorder, but it is likely to be the experience of stress or trauma that decides whether the genes are expressed.
  • Indicates the important & inextricable link between nature & nurture.
• Evaluation of the nature-nurture debate- :/:

  • Our genetics can affect our experience of our environment, eg Kagan (1982) put forward the Temperament hypothesis, whereby babies that are born with innate friendliness & trust were more likely to become securely attached.
  • This is in opposition to the traditional thinking about caregiver sensitivity predicting attachment type- indicates a possible direction for the interaction between nature & nurture.
• Evaluation of the nature-nurture debate- :/:

  • Epigenetics refers to the idea that we are born with 'dormant' genes which may or may not be 'switched on' by environmental triggers such as nutrition or stress.
  • Once activated, these can then be passed onto subsequent generations in their active state, ie the affect on the offspring from birth, eg cloning doesn't produce exact copies, as the adult individual from whom the DNA is taken will contain epigenetic material that was produced by environmental effects in the donors lifetime. This means that the clone will be a product of both genetics & environmental experience.
  • Indicates the incredibly complex interaction between our nature & nurture.