However one weakness of this is that the results found by Carey and Gottesman (1981) found only a 87% concordance rate and therefore this suggests that genes is not the only factor that is causing OCD otherwise it would be 100%. This means that environmental factors must play a role as well. In addition to this, it seems to be the occurrence of OCD that is hereditary not the specific symptoms again suggesting an environmental contribution. Therefore, this weakens the explanation of genes as a cause of OCD as it shows that genes is not solely responsible and there must be other factors that contribute to OCD.
Another biological explanation of OCD is the Neuroanatomical explanation which suggests that OCD is caused by a problem with a part of the brain, the OFC caudate nuclei loop. The orbital frontal cortex sends a message of panic to the caudate nucleus. A normal brain would decide whether or not this issue is important and if it is, it would get passed on to the thalamus to take action. If the message isn’t important or has already been dealt with it will filter out ending the circuit. However in a brain of an OCD sufferer, the caudate nucleus does not work correctly and send the potentially faulty message of panic to the thalamus which then carries out the action e.g. washing hands. This will keep repeating on a loop which is why someone with OCD performs compulsions which are repetitive rituals.
The explanation of OCD is strengthened by supporting research. In a study conducted by Schwartz (1996) PET scans indicate that OCD patient’s exhibit increased glucose metabolism in the OFC caudate nuclei loop. When compared with a control group, it has been found that people with OCD burn energy more rapidly in this network. This increased metabolism is correlated with the severity of OCD. This is also supported by Dougherty (2002) who when studying results of cingulotomies which remove parts of the brain that help the OFC talk to the caudate nucleus, found that 45% of patients responded well to this treatment and had reduced anxiety levels. This research shows that a fault in the OFC caudate nuclei loop is correlated with OCD and therefore strengthens this as an explanation of OCD.
However there is contradicted theory which weakens this explanation. A recent study conducted by Moritz (2009) has questioned the role of the OFC because OCD patients did not perform abnormally on cognitive tasks related to the OFC. Because of this, researchers concluded that OFC dysfunction may be more subtly than previously thought meaning that this factor may only play a small part in the cause of OCD, suggesting other factors are involved therefore weakening this Neuroanatomical explanation.
A problem with the biological explanation to understanding OCD is that it is reductionist as it reduces behaviour down to one sole cause, not looking at how other variables may interact and cause the OCD. The weakness of this is that by only looking at one factor, we do not gain a valid in depth understanding of all possible causes, meaning that if only the biological cause of OCD was treated, only part of the problem is treated. However, it could be argued that reductionism is also a strength as by focusing on one factor alone, you can isolate cause and effect and fully understand the role that the biological factor plays.
In conclusion, it can be said that even though the biological explanations do propose a valid account of what causes OCD, therefore are clearly other factors involved such as the environment. In addition, both explanations have contradictory evidence showing that more research is needed in this area in order to be able to give a completely valid and reliable explanation of OCD.
Here's what a teacher thought of this essay
The writer has written a very concise and succinct essay which explains well biological explanations for OCD. There has also been evidence given to support or critique both the role genetics play as well as the neuro-anatomical argument. The writer has also consistently referenced the work. The essay could be improved by giving a good explanation of OCD and its symptoms as well as the biological perspective at the beginning. However, it is clear that the writer understands what has been written and has referenced sources.