Discuss one or More Biological Explanation for Schizophrenia

The biological theory on Schizophrenia is a determinism theory which states that Schizophrenia is caused by our genetics and things that are involved in our bodies. The biological theory states that the cause of Schizophrenia is due to issues such as our genes, and dopamine levels, and therefore it can be cured by looking at these issues.

The first biological explanation I will look at is the genetic theory of Schizophrenia. There is a 1% chance of someone having schizophrenia in general, however this figure increases when certain relations have schizophrenia too. For example; If one parent has schizophrenia, the chances increase to 10%, if two parents have the illness, this increases again to 40% and if an monozygotic twin is born with schizophrenia, then it is 50% likely the other twin will have it too. However, this could be just because of the similar environment the children are reared in, rather than the genetics involved, it could just be the environment. Kendler et al. Stated that there is no way of telling wether schizophrenia is due to environmental factors, or as the biological theory states, genetics. He said as the blood tie increases, so does the similarity of the environment, and therefore it cannot be proven.

Kety et al. (1975) looked at this theory by doing an adoption study. He looked at schizophrenic children who had been adopted, and then found their biological family. He results showed that 14% of the adopted child's relative also had schizophrenia, thus showing that it is not just the environment that plays a role, because the child was not brought up in that environment. Wender et al. Reversed this study: He founds no increase among adoptees with biological parents without schizophrenia, but with a schizophrenic point; futhur proving Kety's theory.

From looking at studies and percentages, it is obvious to see that genetics does play a role in the likelihood you will get schizophrenia however genetics is only a factor. It cannot be used to explain the whole cause of why schizophrenia develops. If it was purely genetics then monozygotic twins would have a one hundred percent chance of getting the illness: as monozygotic twins have the exactly the same genes: however this is not the case, as monozygotic only have a 50% chance of getting schizophrenia, meaning there must be other factors that play a role in the chance of developing the illness.

Another biological explanation is the dopamine hypothesis. This states that schizophrenia is caused by too much activity of the neurotransmitter dopamine at certain synaptic sites. There is evidence which supports this hypothesis. Firstly, phenothiazines (which are drugs that act by blocking dopamine at the synapse) are effective in alleviating some of the major positive