The biological Approach focuses on two assumptions on where our behaviour comes from
- that it is a result of our genes that we have this conception
- that our behehaviour is controlled by the activity within the central nervous system ( the brain)
Twin Adoption Study
There are two types of twins
- Monozygotic - Identical twins devloped from the same egg therefore genetically 100% the same
- Dizygotic - two babies that share the womb at the same time ( developed from two different eggs ) 50% of genes the same.
Twins studies are used to see if behaviours are shared by those genetically similar. Psychologists do this by looking at the cocordance rates between there behaviour traits.
An example of this is if one twin develops Schizoprenia psychologists would look to see if th other twin develops this behaviour. By doing this on a larger scale they can look and see the likelyhood of one twin developing schizophrenia because of the other twin has it.
About adoption studies
psychologists look at adoptions studies to find out whether behavioural traits are due to Nature ( genetics) Nurture ( enviornmental) factors. This is because adopted children share no gentics with their family however they live in the same environment. Also they share 50% of their biological parents genes but don't share the same environmental factors.
By studying children adopted at birth they can seperate genetic factors and environmental factors that may influence their behaviour. If psychologists find their is a similarity of their behaviour with their biolgocial parents in addition to the adoptive parents they will know its down to genetics.