The nature-nurture debate

• Nature

  Psychological characteristics are inherited
• Heritability coefficient

  • used to assess heredity
  • It’s a numerical figure ranging from 0 to 1.0 (1 meaning it is 100% genetic)
  • General figure for IQ is 0.5 - suggesting both inheritance and environment have an influence on intelligence
• Nurture

  • Psychological characteristics shaped by the environment; it isn't due to our genetic makeup
  • We are born with a blank slate and we learn how to behave though the environment were in

   
• Relative importance of heredity and environment

  • The nature nurture debate is impossible to answer
  • Environmental influence occurs before he child has even been born
  • Realistically the two are intertwined together and we shouldn’t try to separate them as difficult to do this e.g twin studies
• twin studies

  • Often share the same environment as well as genes
  • Because of this we can look at the relative contribution of each influence in terms of what we think and do
• interactionist approach of debate

  • attachment (bowlby’s monotropic theory)
  • diathesis stress model (schizophrenia and offending behaviour)
  • epigenetics
• epigenetics

  • Refers to a change in our genetic activity without changing your genetic code
  • A process that occurs through life and is caused by interaction with the environment e.g lifestyle choices such as smoking
• Epigenetic marks

  tell our bodies which genes to ignore and which genes to use which may influence the genetic codes we pass onto our children
• Ressler (2014)

  • Gave mice an electric shock every time they were exposed to a small of acetophenone
  • The mice showed a fear every time they smelt the scent
  • The mice children also displayed a fear of the scent and their grand children
• always use 2 topics in nature nurture debate ( e.g schizophrenia, relationships, forensics)
• Nativists:

  • Anatomy is destiny
  • Our environment has little input on our behaviour
  • Its very controversial e.g intelligence, race

   
• Empiricists

  • Behaviour can be changed by altering the environment
  • Behaviour shaping  practical application in therapy
  • However, you cant completely ignore an individuals biological makeup
• Shared vs unshared environment

   

  • Twins sharing the same environment is a big problem when trying to distinguish between nature vs nurture
  • Psychologists try to look at twins reared apart; but they still tend to share the same environment (other family members bringing them up)
  • May have shared the same environment before separation
• Constructivism

  • People create their own ‘nurture’ by actively seeking environments that are appropriate or their ‘nature’’
  • For example, introverts will seek to be around other introverts
  • This environment then affects their development
• Genotype-environment interaction: Scarr (1983)

  1. Passive interaction - the parents genes influence the way they treat their children
  2. Evocative interaction - the child's genes influence and shape the environment they grow up in
  3. Active interaction: the child creates its own environment through the people and experiences it selects