Nature- nurture

• Nature

  • Greatest influence come from heredity.  
  • Abilities are innate and characteristics are inherited.
  • Capacities are fixed at birth, change is not possible.
  • Animals are born with 'fixed action patterns
  • Behaviour is instinctual and biologically determined.
  • IQ fixed at birth.
  • All individuals born unequal so society remains unequal. 
• Nurture

  • Key influence is the environment
  • Characteristics can be learned and developed.
  • Able to achieve all given enough time and opportunity.
  • All behaviour is learned
  • So a change in environment leads to a change in behaviour.
  • Behaviour isn't fixed
  • IQ not predetermined at birth, social conditions will improve or depress IQ.
• Diathesis stress model

  = Suggests behaviour is caused by a biological or environmental vulnerability which is only expressed when coupled with a biological or environmental trigger.

  • Eg: a person who inherits a genetic vulnerability for OCD may not develop the disorder, but combined with a psychological trigger this may result in the disorder appearing.
• Interactionist approach

  = Any behaviour can be a combination of nature and nurture

  • Eg: Bowlby claimed that a babys attachment type is determined by continuity of parental love (environmental influence)
  • Kagan proposed that a babys innate personality also affects the attachment, so nature creates nurture so environment and heredity interact.
  • Interactionist= how nature and nurture interact
• Epigenetics

  = A change in our genetic activity without changing the genes themselves.

  • Caused by interaction with the environment
  • Events on our life leave marks on our DNA which switch genes on or off.
  • Eg: smoking has a lifelong influence and change the way genes are expressed so may influence genetic codes of our children.
• Evaluation- adoption studies

  • Are useful as they separate the competing influences of nature and nurture.
  • If adopted children are found to be more similar to their adoptive parents this suggests the environment is the bigger influence.
  • Whereas if they are more similar to their biological parents, then genetic factors dominate.
  • Found genetic influences accounted for 41% of the variance in aggression.
  • So research can separate influence of nature and nurture.
• Evaluation- counterpoint

  • Research suggests that nature and nurture aren't separate and cant be pulled apart.
  • Suggested that people create their own nurture by actively selecting environments that are appropriate for their nature.
  • Eg: a naturally aggressive child is likely to feel comfortable with children who show similar behaviours and choose their environment. Their chosen companions further influence their development.
• Evaluation- epigenetics

  • Example of how environmental effects can span generations= events from WW11
  • Nazis blocked food distribution to Dutch people.
  • Women who became pregnant during famine went on to have low birth weight babies. These babies where twice as likely to develop schizophrenia when they grew up.
  • Supports view that life experiences of previous generations can leave epigenetics markers that influence health of children.
• Evaluation- real world application

  • Research suggests OCD is a highly heritable mental disorder.
  • Such understanding can form genetic counselling because its important to understand that high heritability doesn't mean its inevitable that the individual will go on to develop the disorder.
  • So people with high genetic risk of OCD because of their family background can get advice about the likelihood of developing the disorder and how they may prevent this.