A01: The Nature-Nurture Debate

• Nature Debate

  • Inherited influences (e.g genes)
  • Derived from nativist theory - Early nativists (e.g Descartes, 17th century) argued that human characteristics are INNATE - the result of our genes.

  Suggests psychological characteristics (e.g intelligence or personality) are determined by biological factors (like genes) and are as inherited as physical characteristics (eye colour or height)

  • The Biological approach is firmly 'NATURE'
• Nurture

  • Environmental influences - Behaviour is a result of our environment

  Derived from empiricist theory that knowledge derives from learning = Empiricists (E.g Locke, 17th century) argued mind is a blank slate at birth and is shaped by interaction with the environment

  • For example, learning, socialisation and experience
  • The behaviourist approach is firmly 'NURTURE'

  Levels of the Environment
• Levels of the Environment:

  Nurture debate:

  • There are differing levels on which the environment affects behaviour:

  Learner (1986) identified different levels of the environment:

  • 1.Prenatal terms: mothers physical and psychological well being during pregnancy: e.g mother smoking or hearing music
  • Postnatal experience:
  • 2. The environment the child grows up in - the impact of parents, siblings, friends etc e.g the social conditions a child grows up in.
  • 3. Political, social, cultural & historical contexts of their world.
• The nature-nuture debate

  • Interactionist approach
  • Diathesis-stress model
  • Epigenetics

  
  

  Are characteristics like personality, intelligence, abnormality etc caused by innate influences (nurture) or the result of learning/environment (nurture)?

  The answer is probably both so modern psychology tends to adopt an interactionist approach - i.e what is the relative contribution of nature and nurture on human behaviour.
• Interactionist Approach:

  Heredity (nature) & env (nurture) have an influence on each other

  • E.g. in attachment child's innate temperament (Kagan 1984) will effect way parents respond which will in turn (Bowlby 1958), effect the child's behaviour.
  • Environment and heredity interact.

  How would interactionist approach explain how nature would influence someone nurture leading to mental illness e.g, sz: mother has sz due to genes she creates an unstable home life (FINISH GC)

  Not really a debate coz all characteristics combine nature & nurture (even eye colour is only .80 heritable).
• Diathesis-Stress Model

  • This is an interactionist approach
  • Genes create a biological vulnerability to a behaviour/illness but it can only be expressed if triggered by some sort of environmental stressor.
  • This can be used to explain why only 1 twin of an MZ pair might develop a mental illness.

  For example, a person who inherits a genetic vulnerability for OCD may not develop the disorder. But, combined with a psychological trigger (e.g a traumatic experience) this may result in the disorder appearing.
• Epigenetics:

  Epigenetics is a change in our genetic activity without changing our genetic code.

  • Its a process that occurs all throughout life & is caused by interaction with the environment.

  Lifestyle and events we encounter (e.g smoking, bedtime, diet, stress, exercise, pollution, trauma, war) leave 'marks' on our DNA (genes) - switching genes on or off (telling our bodies which genes to silence and which to express).

  • This has a lifelong influence and can be passed on to future generations influencing the genetic makeup of our offspring.
• Dias & Ressler (2014)

  Acetophenone and mice babies:

  Procedures:

  • Gave male lab mice electric shocks every time they were exposed to the smell of acetophenone.

  Findings:

  • Mice showed a fear response as soon as the scent was present. What's interesting is the mice's children and grandchildren also suffered the same despite never previously being exposed to the smell or the father.
• Measuring nature and nurture

  Concordance - the degree to which 2 people are similar on a particular trait.

  Heritability - proportion of differences between individuals in a population, with regards to a particular trait, due to genes. 0.01 (1%) is vert little contribution, 1.0 (100%) means genes are the only reason.

  • The figure for heritability in IQ is about 0.5 (Plomin 1994)