psychopathology - OCD Flashcards
What is OCD?
OCD is an anxiety disorder classified by obsessions and compulsions.
Obsessions = reoccuring and persistent thoughts.
Compulsions = repetitive behaviours.
Outline the behavioral characteristics of OCD
The behavioural component of OCD centres on the compulsive behaviour and for sufferers of OCD, compulsions have two properties.
Firstly, compulsions are repetitive in nature and sufferers will often feel compelled to repeat a behaviour, for example, repetitive hand washing.
Secondly, compulsions are used to manage or reduce anxiety, for example, the excessive hand washing is caused by an excessive fear of germs and bacteria and is therefore a direct response to the obsession.
Outline the emotional characteristics of OCD
The emotional characteristics of OCD are mainly characterised by anxiety which is caused by the obsessions, however some sufferers of OCD also experience depression.
Obsessions are persistent and/or forbidden thoughts and ideas, which cause high levels of anxiety in OCD sufferers.
Furthermore, OCD can often lead to depression, as the anxiety experienced can often result in a low mood and loss of pleasure in everyday activities, because everyday activities are interrupted by obsessive thoughts and repetitive compulsions.
Outline the genetic explanation for OCD
Genes may create a vulnerability (risk of developing) to OCD. There is evidence that OCD runs in families.
Lewis (1936) found that 37% of patients with OCD had parents with the disorder. The diathesis-stress model suggests that, along with this vulnerability, the environment may trigger OCD.
There are many candidate genes involved in OCD (for example, those involved in the serotonin and dopamine systems), and it is polygenic: several genes are involved (perhaps up to 230).
The SERT gene is linked to the neurotransmitter serotonin and affects the transport of the serotonin (hence SERotonin Transporter), causing lower levels of serotonin which is also associated with OCD (and depression)
Evaluation of genetic explanation of OCD - Identical twins
Supporting evidence from research showed that 68% of identical twins were both diagnosed with OCD, compared to 31% of non-identical twins, suggesting there is a genetic basis.
However, can’t be only genetic explanation otherwise would be 100%.
Evaluate the genetic explanation of OCD - Candidate genes
There are too many candidate genes for OCD - potentially hundreds. This means that finding a definitive genetic cause is very unlikely, reducing the usefulness of this explanation.
Evaluate the genetic explanation of OCD - trauma
There is evidence that the environment is very influential in developing OCD.
OCD was more severe in patients who had experienced traumatic events in their lives, and even more severe where patients had experience more than one event. This suggests the environment is more important than biology in developing OCD.
Outline the neural explanation of OCD
- Low levels of serotonin leads to impaired transmission of mood-relevant information, leading to a lowered mood, and also obsessive thoughts.
- Abnormal functioning of the left parahippocampal gyrus leads to more processing of unpleasant emotions, which is a feature of OCD.
- Abnormal frontal lobe functioning leads to impaired decision-making, leading to symptoms of OCD.
Evaluation of neural explanation for OCD - Studies
Supporting evidence from antidepressant studies shows that increasing serotonin levels reduces OCD symptoms, suggesting serotonin has a role in the development of OCD
Evaluation of neural explanation for OCD - cause-effect
The cause-effect relationship not known- it could be that changes in the brain are a result of OCD, rather than causing it in the first place. This weakens the neural explanation.
Explain drug therapy for OCD
SSRIs (selective serotonin reuptake inhibitors) are the most commonly prescribed drugs for OCD. These work by blocking the transporter mechanism that re-absorbs serotonin into the presynaptic cell after it has fired. As a result, more serotonin is left in the synapse to be absorbed by the post synaptic cells.
Dosages vary with the patient, and it takes 3-4 months for benefits to show. An example of an SSRI is Fluoxetine. Often SSRIs will be combined with CBT.
Evaluate drug therapy as a treatment for OCD - Soomro
One strength of drug therapy for OCD was shown by Soomro (2009). In this study, it was found that SSRIs were significantly better than placebos (fake drugs) at reducing OCD symptoms, showing that the drugs are effective.
Evaluate drug therapy as a treatment for OCD - easy
Compared to psychological treatments, drug therapy is easy and non-disruptive, as the patient just needs to take a pill rather than undergoing lengthy therapy sessions. This is a strength because the treatment suits people no matter what their lifestyle, job, and so on.
Evaluate drug therapy as a treatment for OCD - side effects
A weakness of drugs is that they can have side effects, for example indigestion, loss of sex drive, blurred vision, weight gain and aggression. This weakens the use of drugs because patients may be less willing to take them, therefore their OCD symptoms will return.
