3. Nature vs. nurture

• The interactionist approach

  • Bowlby suggested a baby's attachment type is determined by the love from your parents (nurture)
  • Kagan proposed a baby's innate personality also affects the attachment relationship (nature)
  • Nature creates nurture so they interact
• Diathesis-stress model

  • Suggests behaviour is caused by a biological or environmental vulnerability which is only expressed when coupled with a 'trigger'
  • Example - OCD
• Epigenetics

  • Change in our genetic activity without changing the genes themselves
  • Caused by interaction with the environment
  • Aspects of our lifestyle such as smoking leave marks on our DNA
  • May go and influence the genetic codes of our children and grandchildren
• Nature

  • Inherited biological characteristics
  • Descartes - all human characteristics are innate
  • Examples - intelligence and personality
• Nurture

  • Influence of experience and the environment
  • Locke (empiricist) - argues that the mind is a blank slate at birth and is shaped by the environment
  • Lerner - identified levels of the environment such as prenatal factors and postnatal factors that affect a foetus
• Measuring nature and nurture

  • The degree to which two people are similar on a particular trait can be represented by a correlation coefficient and is called concordance
  • Provides an extent to which a trait is inherited
  • A figure of 0.01 means that genes contribute almost nothing to individual differences and 1.0 means genes are the only reason for individual differences
  • General figure for hereditability in IQ is about 0.5 (half genetic, half environmental)
• AO3 - Hardline stance does not allow a large picture to be established

  • Menstrual cycle believed to be completely endogenous and a result of biological factors such as hormones oestrogen and progesterone
  • Due to research conducted (Stern and McClintock) environmental factors such as diet and stress impact this type of infradian rhythm as well as explaining the causes of irreguality
  • Suggests menstrual cycle is due to nature and nurture
  • Illustrates irregularity as normal
  • Real world value
• AO3 - Real world application

  • Neural plasticity - brain can reorganise itself by forming new neural connections throughout life (include definition)
  • Maguire et al. study on taxi drivers - nurture has an effect on nature as the more routes taxi drivers had driven, the larger their hippocampus (positive correlation)
  • Diathesis-stress model and OCD - genetic counselling allows people to prevent certain triggers for the onset of OCD, can receive advice
  • Real world value
• AO3 - Meaningless distinction

  • Grown increasingly complex and do not act independently
  • Psychopathology - both a genetic predisposition and an appropriate environmental trigger required for a psychological disorder to develop
  • Diathesis-stress model (OCD) - candidate genes and an environmental trigger such as trauma or stress
  • Real world value