Obsessive Compulsive Disorder (psychopathology) Flashcards
Psychopathology
Genetic explanation
this explanation suggests that we may inherit genes that make us vulnerable to developing OCD. the use of twin studies and concordance rates allow us to see this genetic vulnerability.
Nestadt (2010)
meta-analysis of 14 twin studies into OCD and found a concordance rate of 68% for monozygous twins and 31% for dizygous twins. As the concordance rate is higher for monozygous, it indicates that OCD is at least partly genetic.
Candidate genes
~specific gene found to be associated with a disease.
mutated SERT gene affects levels and regulation of serotonin = OCD. however, OCD is believed to be polygenic so a combination of genetic variations increase vulnerability.
Taylor (2013) reports over 200 genes may be linked to OCD.
Cognitive characteristics of OCD
these are the obsessions. intrusive,unwanted and unpleasant thoughts. the sufferer is often aware that these thoughts are irrational yet cannot help but feel the anxiety.
Behavioural characteristics of OCD
these are the compulsions. repetitive behaviour which are done to reduce feelings of anxiety. another behavioural characteristic is avoidance.
Emotional characteristics of OCD
those with OCD will often experience the emotion of extreme anxiety because of their obsessions and compulsions. OCD can result in depression, they may also feel guilty.
Limitations of the genetic explanation
it ignores the influence of the environment/nurture. if OCD was due to genetics alone, concordance rate for monozygous twins would be 100% as they are genetically identical. there has never been a 100% concordance rate, suggesting the cause of OCD is not just genetics.
Strength of the genetic explanations
Ozaki et al (2003) looked at two unrelated families and found that 6/7 participants with the mutation on the SERT gene had OCD or a related disorder. this supports the idea that OCD may be inherited and supports the role of the SERT gene.
Neural explanations
Neural factors look at brain structures or biochemicals/neurotransmitters that may influence the development of OCD. Specifically, the role of serotonin and the basal ganglia.
Serotonin
Serotonin is a neurotransmitter which controls our mood. Low levels of serotonin have been found in those with OCD. This means messages about regulating mood are not normally transmitted - so may explain the intense anxiety (emotional characteristics) felt by sufferers with OCD, that may then cause the obsessions.
Basal ganglia
The basal ganglia is a set of brain structures located at the base of the forebrain. One of their functions is related to making decisions surrounding movements that are likely to lead to positive consequences and avoiding unpleasant things. It has been argued that an abnormality in the basal ganglia might lead to OCD. This can explain the compulsions that are done to avoid the unpleasantness of the obsessions.
Evaluation of the basal ganglia
Evidence to support the role of the basal ganglia in OCD comes from Wise and Rapoport (1989). They found that OCD is common in sufferers of Huntington’s chorea, Parkinson’s and Tourette’s. These three illnesses are movement disorders, and all involve abnormalities in the basal ganglia, so perhaps the basal ganglia can account for their symptoms of these disorders which has then caused them to develop OCD too. This supports the role of the basal ganglia as an explanation of OCD. However, not every sufferer of these disorders has OCD which suggests that this cannot be the only explanation.
Evaluation of the role of serotonin
There is evidence to support the role of serotonin in the development of OCD. OCD is often treated with the use of drugs such as SSRIs. They work by blocking the reuptake sites on the presynaptic neuron so that serotonin remains in the synapse for longer to increase the levels of serotonin. This then relieves symptoms of OCD. This supports the idea that low levels of serotonin must be linked to OCD, as treatments often deal with this disorder by increasing these levels. However, cause and effect is hard to determine. Whilst it shows a relationship between serotonin and OCD, it cannot say for certain that low levels of serotonin cause OCD. Perhaps OCD is caused by another factor and serotonin levels decrease because of the disorder itself.
Biological approach to treating OCD: drug therapy
As we have seen, low levels of serotonin have been linked to the development of OCD. Therefore, treatments for OCD tend to involve increasing the levels of serotonin to decrease symptoms.
SSRIs
Selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine are antidepressants that are prescribed to treat many mental disorders including OCD. SSRIs block reuptake sites on the presynaptic neuron, so serotonin remains in the synapse for longer, meaning it has more chance of being taken up by the receptor sites on the postsynaptic neuron. This then increases serotonin levels, and decreases the symptoms of OCD (roughly after three/four months of use).
Alternatives to SSRIs
Some people may try SSRIs yet show little improvement after several months. They may then be prescribed an alternative drug or combined with SSRIs. One of these alternatives are known as tricyclics. These work in a very similar way to SSRIs however also work on other neurotransmitter systems such as norepinephrine. An example is known as Clomipramine. However, these do have more severe side effects that SSRIs so will often only be prescribed when SSRIs have been tried but have not helped the patient.
Evaluation of drug therapy: effectiveness research
There is research to support the effectiveness of SSRIs in the treatment of OCD. Soomro et al (2009) reviewed 17 studies and found that SSRIs were more effective that placebos in reducing symptoms of OCD. 70% of those who received SSRIs saw a decrease in their symptom severity. This supports the fact that SSRIs can be helpful for those suffering with OCD.
Evaluation of drug therapy: side effects
An issue with the use of drugs to treat OCD is that there are many side effects. Side effects include anxiety, digestive, visual and sleeping problems. Whilst they wont be experienced by everyone, those that do might be replacing one set of problems with another. Furthermore, the sufferer may stop taking the drugs altogether if the side effects outweigh the symptoms of OCD. This limits how appropriate the use of drugs are to treat OCD if drugs are adding to the problem.
Evaluation of drug therapy: combined with psychological therapy
A further issue is that there is evidence to suggest that drugs are best when combined with a psychological therapy. For et al (2003) carried out a study using OCD patients and found that clomipramine when combined with cognitive behavioural therapy (CBT) was more effective at reducing their symptoms than when clomipramine alone was used. This limits the use of drugs when treating OCD as it seems to be the case that psychological therapies such as CBT are of more benefit (either alone or when combined with drugs).
Evaluation of drug therapy: cheap & little effort
A strength of the use of drugs is that they are cheap and require little effort from the patient. A months’s worth of drugs such as SSRIs costs the NHS roughly £4.21 to dispense. However, CBT can cost the NHS hundreds of pounds per patient depending on how many sessions they need. CBT also requires effort from the patient in terms of attendance to sessions and completing homework tasks whilst drugs are an easy way to combat symptoms if regularly taken. This supports the use of drugs in terms of their cost-effectiveness and ease of use for patients.
Further limitation: unethical
However, drugs are considered a more unethical approach than psychological therapies. This is because they are not very empowering. They involve the patient doing as they are told (following the dosage) and don’t require any real effort. In contrast, psychological therapies such as CBT only lead to improvement through the effort of the patient. This might be more empowering for the patients.
