Biological explanations of OCD 16 mark question

“Two students were discussing theri friend David who has recently been diagnised with obsessive copulsive disorder (OCD). Melanie says, ‘It wasn’t a surprise to me that David has OCD because his mum is always tidying things, putting them in order and checking switches.’ Emma says, ‘Really? I didn’t know that. I always thought that people with OCD have something in their brains that makes them behave in that way.”

Outline and evaluate neural and genetic explanations for obsessive compulsive disorders. Refer to the conversation in your answer. (16 marks)

Genetic explanatiosn of OCD can be explained initially by family studies, as research suggests that whether a person develops OCD is at least partly due to their genes. This is likely to explain why patients of OCD often have other family members that have been diagnosed with OCD. Lewis’ research had shown that 37% if patients with OCD also had parents that were diagnosed with OCD. This is seen in the text where it says, “his mum is always tidying things, putting them in order and checking switches.” The results of Lewis’ study shows that there may be genetic patterns that can be passed through family genses that causes the OCD, or it could be Social Learning Theory where people who have grown up with parents that had OCD may grow up to believe that those behaviours are normal which may have been the case with David. Another genetic explanation of OCD os cadidate genes. Candidate genes are genes in which have been connectdd to the development of OCD which makes those who are carrying those genes vulnerable to developing OCD. For example, the COMT gene is associated with the regulation of dopamine and one variation of the COMT. gene results in higher levels of dopamine, and this variation of the gene is more common in those that have been diagnosed with OCD comapred to those that haven’t. OCD is said to be polygenic meaning that the development of OCD is not determined by one specific gene but by numerous Genes. Taylors research had shown that 230 genes may be involved in the development of OCD.

A critcism of the genetic explanation of OCD is that it does not take into account environmental factors such as trauma. Comer et al had found that more than half of their patients that had OCD, had experienced traumatic events in their past and OCD was more severe in those that had experienced multiple traumatic events. This is a disadvantage because it shows that OCD is less likely to be genetic in most cases. Another criticism of the genetic explanation of OCD is that there are too many possible candidate genes that may be involved in the development of OCD. This is a disadvantage becauseit means that the genetic explanatiion may not be that useful as it ptovides not predictive value.

The neural explanation of OCD can be initially explained through the role of Serotonin. Serotonin is believed to help with mood regulation. If a person has low levels of serotonin then the normal transition of mood related information does not take place, and so mood and other mental processes are affected. This then means that in atleast some cases of OCD, OCD may be explained by a reduction in the funtioning of the serotonin system in the brain. This is seen in the text where it says, “people with OCD have something in their brains that makes them behave in this way.” Another explanation of OCD is impaired decision making and the orbitofrontal cortex. In some cases of OCD, OCD seems to be associated with impaired decision making which is caused by abnormal functionung of the lateral frontal lobes of the brain which are responsible for decision making. Another brain region associated with OCD is the orbitofrontal cortex which is a region that converts sensory information into thoughts and actions. PET scans find higher activity in the orbitofrontal cortex in patients with OCD than in patients without OCD.

An advantage of the neural explanation for OCD is tat there is supporting evidence as some antidepressants work purely on the serotonin system and increasing the levels of serotonin. Such drugs are effective in reducing OCD symptoms which suggests that the serotonin system is involved in OCD. Another advantage of the neural explanations of OCD is that serotonin may link with depression depression as many people who have suffered from OCD have become depressed, and having two disorders at the same time is called co-morbidity. This depression involves disruption of the serotonin system which then leaves the logical problem when i \n