Nature- nurture debate

Interactionist approach

Nature- nurture debate seeks to answer the question of whether our behaviour is more influenced by nature or nurture

Not really a debate because any behaviour/ characteristic arise from a combination of both

For example, bowlby claimed that a baby’s attachment type is determined by the warmth and continuity of parental love (environmental influence)

Whereas, Kagan proposed that a baby’s innate personality (temperament) also affects the attachment relationship

This means that nature (childs attachment) is likely to influence nurture (parent’s response), so heredity and environment interact

Psychologists are now more likely to ask about the relative contribution of each influence - therefore the nature- nurture debate is really about how they interact (interactionist approach)

Diathesis stress model

Suggests behaviour is caused by a biological or psychological vulnerability which is only expressed when coupled with a biological or psychological stressor

For example, with OCD, a person who inherited a genetic vulnerability for OCD may not develop the disorder , but combined with a psychological stressor this may result in the disorder appearing

Epigentics

Refers to a change in our genetic activity without changing the genes themselves

It is a process that happens throughout life and is caused by interaction with the environment

Aspects of our lifestyle or events we encounter leave marks on our DNA, which switches genes on or off

This explains why factors such as smoking have a lifelong influence even after you stop- such influences have changed the way your genes will be expressed

Even more remarkably these epigentic changes may go on and influence the genes of our children, as well as their children

Epigentics therefore introduces a third element into the nature- nurture debate - the life experiences of previous generations

Key concepts of the debate

Nature- refers to inherited influences or heredity, early nativists argued that all human characteristics are innate , psychological characteristics like intelligence or personality are determined by biological factors just as physical characteristics such as eye colour

Nurture- refers to the influence of experience and the environment, empiricts argue that the mind is a blank slate at birth which is then shaped by the environment

Measuring nature and nurture

Degree to which two people are similar on a particular trait can be represented by a correlation coefficient and this is called concordance

Such concordance provides an estimate of the extent to which a trait is inherited - called heritability

Heritability is the proportion of variation in a trait within a population

A figure of 0.01 means genes contribute almost nothing to individual differences and a figure of 100% means genes are the only reason for individual difefrences

General figure in IQ is about 0.5 across mutliple studies in varying populations - means about half of a persons intelligence is determined by genetic factors