NATURE refers to our innate potential that is influenced entirely by physiological and genetic factors. NURTURE refers to the influence of the environment into & all the learning experiences we have after we are born. The nature-nurture debate has been hotly debated in psychology. At the outset of psychological research the nature-nurture debate was a point of argument between researchers from the behaviourist tradition and other approaches. More recently it has divided researches with regard to social and racial differences in intelligence.
Nowadays it’s hard to believe that something as complex as human behaviour can be completely explained by either side of the argument, it’s more likely to be a product of both, as suggested by the Psychologist Robert Plomin. He would like to see the nature-nurture debate end as he says most human behaviours are not influenced by nature or nurture but by nature and nurture. He makes the point that twin and adoption studies have provided evidence for the fact that there is a genetic component to personality, intelligence and general behavioural disorders such as Schizophrenia and Autism.
However the genetic influence on these traits and behaviour is only partial, genetics account for on average half of the variance of most traits therefore the environment must account for the rest according to Plomin. This means that they are interdependent. An approach that belongs on the interdependent side of the argument is the cognitive-developmental approach. A key assumption of this approach is that development occurs through the twin processes of nature and nurture.
Piaget believed that children were innately curious and programmed to learn (nature) but they needed the right sort of stimulation and environment to be able to do this adequately (nurture). However a criticism to this approach is that Piaget underestimated children’s abilities, this produces a difficulty in his theories and suggests that children are not the way he envisioned them. This could indicate that they are not innately curious and even if provided with the right environment, don’t learn.
This can be compared to the Leaning Approach; a criticism with this approach is that it doesn’t consider the effect of nature, similar to a criticism of the physiological approach, which doesn’t consider the effect of nurture. If the theories are proved false it’s tempting to say that that indicates nature and nurture have no effect individually, but must work together. An approach that believes that nurture is entirely responsible for our behaviour is the learning approach. The learning approach presents the assumption that all behaviour is learnt, through interactions with the environment, and at birth we are a blank slate ready to develop.
Evidence for this comes from Watson’s study of little Albert. Albert was an 11-month-old baby when the study began; Albert was presented with a white rat, to which he responded with curiosity. After several sessions the presentation of the white rat was accompanied with a loud noise to which Albert responded with fear. After several sessions Albert displayed fear as soon as the rat was presented even without hearing the loud noise. This showed Albert had learnt to associate the rat with a loud noise, which he was frightened of. Albert generalised this fear with other things similar to the rat such as a white rabbit and a white beard.
Albert had learnt this behaviour. So according to the learning approach it therefore follows that nurture is solely responsible for human development. Watson’s study was On the other hand is the physiological approach. This approach presents the assumption that genetics are responsible for human behaviour. For example research into genetics has shown there to be genes responsible for certain type of behaviour and characteristics for example tongue rolling and eye colour, and more controversially research has been carried out to find a gene responsible for homosexuality and criminality.
Evidence to support this theory comes from research into Schizophrenia. This research has shown there to be an excess of dopamine in the brains of schizophrenics. Schizophrenia has been shown to run in families, 10 out of every 100 children who have one biological parent with schizophrenia go on to develop schizophrenia whereas only 1 or 2 in every 100 in the general population develop schizophrenia. Twin studies on monozygotic (identical twins) have also indicated that genetics are responsible for schizophrenia, as if one twin is schizophrenic there is between a 35 and 58% chance of the other twin also developing schizophrenia.
Of course this is only a correlation and this relationship could be caused by another variable. Twin studies are hard to conduct because the necessary situation doesn’t occur particularly frequently in the population, therefore the sample is limited and difficult to generalise. This affects the reliability and validity of the results. The idea of the causes of schizophrenia is explored further in clinical psychology. Schizophrenia is the most commonly diagnosed form of mental illness; 1% of the whole population will be diagnosed at some point in their lives has having schizophrenia.
Schizophrenia doesn’t seem to have one single cause but is rather the product of a relationship between biology, psychology and culture. Which suggests both nature and nurture play a role in the development of schizophrenia. As I said earlier twin, adoption and family studies give the clearest indication that genetics play a role in the development of schizophrenia. 10% of children with a schizophrenia parent will go on to develop the disease. This however, because it’s only a correlation, could be caused by another factor, for example the environment.
Studies have been carried out using twins to find out the concordance rate of schizophrenia in twins. The increased risk of developing schizophrenia could be the result of difficulties that have arisen during the rearing of a child by a parent with such a disorganised personality. However adoption studies have been carried out which also suggest that genetics are responsible for schizophrenia. Heston (1966) compared the adopted children of 77 schizophrenic mothers with the adopted children of 50 normal mothers and found the former to be 5 times more likely to be admitted to hospital with schizophrenia.
This study also shows that those children of schizophrenic parents were more likely to go on and be diagnosed as psychopaths, behaviourally disordered or neurotic. The study by Heston rules out the possibility that the experience of being adopted leads to the development of schizophrenia as the control group didn’t go on to develop higher levels of schizophrenia. However the sample isn’t large so is difficult to generalise and this type of situation doesn’t occur frequently so it is hard to do this type of investigation.