Explanation

• The genetic explanation for OCD focuses on the roles of genes in contributing to the development of the disorder. Every individual has chromosomes, these are made up of Genes. Our genes contain DNA which has the code for both our physical and mental (mental disorders) characteristics.
• The genetic explanation focuses on the role of candidate genes, these are genes which increase an individuals vulnerabillity to developing the disorder, for OCD, many of these have been found to be related to the regulation of serotonin.
• OCD has been found to be polygenic, meaning that it is caused by a combination of genes working together. Research has suggested that in OCD, there are roughly 230 genes which can work in combination and are related to genetic vulnerability to OCD.
• The origins of OCD varies from person to person, as one group of genes may cause OCD in one person, but a different group in another.
• The second half of the biological explanation is referred to as the neural explanation; it has been found that physical and psychological characteristics are also determined by the nervous systems (which composes of the brain and spinal cords, connected and communicating with one another via neurones).
• Neurotransmitters are responsible for relaying information from one neurone to another. PET scans have shown low levels of serotonin to be associated with the development of OCD. If an individual has low serotonin levels, they are more likely to have a low mood. PET scans have also shown that OCD sufferers show relatively high levels of activity in the orbital frontal cortex, an area associated with decision making and thinking processes and the parahippocampal gyrus is found to function abnormally for OCD sufferers which is responsible for processing unwanted emotions
• A strength of biological exp for OCD is that it has been supported by twin studies. Nestdat (2010) found a 68% concordance rate in monozygotic twins (twins that share the same genetic makeup) compared to a 31% concordance rate dizygotic (twins that have different genetic makeups) this supports the genetic explanations understanding and proposal of genetic vunerability to the disorder.
• However, given that the concordance rate is limited to 68%, one can suggest that the biological explanation to OCD is reductionist in that it fails to take into account social or environmental factors which might contribute to the development of the disorder. As Cromer (2007) found that half of the patients within his sample of OCD sufferers, had experienced a traumatic event, and that those who had experienced more than one traumatic event were shown to have worsened symptoms. Thus suggests biological t's may not be helpful for those who have ocd as a result of social factors.
• The neural explanation for OCD is also supported by Zohar who gave a drug which reduces serotonin levels to 12 ocd patients and 20 non-sufferers. He found that symptoms of OCD were more enhanced in the 12 OCD patients than the non-sufferers, supporting the understanding of OCD being related to abnormal levels of serotonin. This supports the understanding that drugs can be given to regulate serotonin production in OCD suffers.
• Furthermore, the biological explanation fails to take into account evolutionary explanations, which supports the understanding that compulsions, such as excessive grooming were behaviours that we adapted to prevent and enable us to fight off infections and to increase our vigilance.