Relative contribution of nature and nurture. Nature and nurture are usually combined or work together. Attachment can be explained in terms of parental love (Bowlby) or child's temperament (Kagan). Environment d heredity
interact.
Diathesis -stress model
Behaviour is caused by a biological and environmental vulnerability (Mathesis ) which is only expressed when coupled with a biologial /environmental trigger (stressor). A person who inherits a genetic vulnerability for OCD may not develop the disorder, however if combined with a psychological trigger (traumatic experience) this may result in the disorder appearing; prenatal childhood sexual or physical abuse, family conflict or life changes.
Epigenetics support interactionist approach
A change in genetic activity without changing the genetic code. Our lifestyle and the events we encounter (smoking, diet, trauma) leave marks on our DNA -switching genes on or off. This has a lifelong influence and can be passed on to future generations. A study on rats ; lacked motherly attention and were unable to cope with stress and passed this on to newer generations of rats.
Nature
nativists; behaviour is caused by innate characteristics eg. biology
Descartes argued that human characteristics are innate: a result of our genes. Psychological characteristics (intelligence and personality) are determined by biological factors .
Nurture
empiricists; behaviour is caused by the environment
Locke argued the mind is a blank slate at birth and is shaped by interaction with the environment. Lerner identified different levels of the environment: prenatal terms (mother smoking, hearing music) and post natal experiences (social conditions a child grows up in).
Measuring nature and nurture
* Concordance = the ° to which people are similar on a particular trait
* Heritability = proportion of differences between individuals in a population, with regard to a particular trait, due to
genes. 0.01 (1%) means there is very little contribution, 1.0 (100%) means genes are the only reason. Plomin found the figure for heritability in IQ is about 0.5.