Evidence for brain developmentNature VS Nurture

Miles Adams

Twin Studies This idea considers the argument that identical twins raised

apart will have dramatic differences in brain development due to the differences in the surrounding environment.

Scientists can easily compare whether nature or nurture has an impact on the brain development of twins by separating them at birth. Any differences in separated identical twins are due to nurture.

Non-identical twins in a similar environment, when compared to identical twins in a similar environment, can be used to prove that differences in brain development are caused by nature.

Thomas Bouchard’s work as part of the Minnesota Twins Project helped prove that identical twins normally have the same brain development but external factors (nurture) are responsible for any differences.

Brain Damage Studies Damage to the brain can easily cause loss of brain

function, i.e. a stroke. Studies are performed on children rather than adults

as the brain is still developing in children. Children with brain damage are compared to those

without to investigate brain development in children with brain damage. Nature or nurture being the main role will be determined if the function develops in the child.

The function developing means nurture is responsible for brain development.

Function not developing despite the nurture means nature is responsible.

Cross-Cultural studies Children brought up in cultures with different beliefs,

social customs and education systems have different environmental influences on them.

Comparing large sample groups of children who are the same age but from different cultures can allow scientists to study the effects of different upbringings on child brain development.

Differences in brain development in different cultures are more likely to be explained by nurture, while similarities are more likely to be due to nature

Animal Experiments Scientists study the effects of different environments

on brain developments of animals of the same species. Differences in brain development are likely to be due

to nurture than nature if they are genetically identical. Rats from a young age are used to see brain

developments in this species. In a study, rats in a stimulating environment had

better developed brains and performed better in tasks than rats in a boring environment. Helping to suggest nurture is responsible.

However, genetically engineered rats lacking the Lgl gene saw a physical change in their brains, helping to provide evidence to show that nature can be heavily responsible.

Newborn Studies A newborn baby’s brain is almost unaffected at birth

by the conditions in the womb. Babies’ brains can therefore help scientists see what

parts of the brain are fully developed at birth. What babies are born with (such as being able to

recognise a face) is natural and what develops over time (like speaking ability) is likely to be a cause of nurture and the environment they are raised in.