Biological Approach
All behaviours are caused by both biological and genetic influences such as hormones, the structure of the brain, neurotransmitters and genetics. Testosterone (a hormone that can affect a male’s behaviour in increased amounts) has been found to be linked to aggression. Hormones can also affect a female’s behaviour during the menopause as oestrogen levels will significantly decrease. A lack of oestrogen in women is linked to depression in women. An example of the structure of the brain having an impact on the person’s behaviour would be a person who suffers from schizophrenia. In post-mortem examinations of schizophrenic patients, it is found that the ventricles in their brain are enlarged. Another factor involved in schizophrenia are neurotransmitters. For example, dopamine. Excessive amounts of dopamine can result in schizophrenia in an individual. Low levels of serotonin (also a type of neurotransmitter) have been linked to depression. Some biological theorists suggest that there is also a genetic component involved in developing schizophrenia. “A person is more likely to develop schizophrenia the closer they are related to a person with schizophrenia” (Gottesman, 1991)
The influence of genetics can be tested by comparing the behaviour of twins. We can study the genetic basis of behaviour. If behaviour is caused completely by genetics then both monozygotic twins should share the same behaviour as they have 100% of the same genes. Also, if behaviour is caused completely by genetics then some sets of dizygotic twins will share the same behaviour and some sets will not as they only share 50% of the same genes. Monozygotic twins have a predisposition to schizophrenia as they share 100% of the same genes.
Evaluation of biological treatments
There are a variety of biological treatments that are used to treat abnormal behaviours. Next I will talk about each treatment and look at the strengths and weaknesses of their effectiveness.