the biological approach - explaining and treating OCD Flashcards
what is meant by neurotransmission?
Arguably, the levels of certain neurotransmitters may cause OCD:
*Dopamine levels are thought to be high in people with OCD. Dopamine is part of the learning pathway and it could be argued that due to this being high, people learn the behaviour of obsession and compulsion.
*Serotonin levels however are thought to be low. Serotonin is associated with happiness and it could be argued that this is lacking in those with OCD. This is known because it can be seen that antidepressant drugs increase serotonin activity have been shown to reduce OCD symptoms.
Outline the impact of genetics in the development of OCD?
It can also be argued that genetics are the cause of the changes in neurotransmission which in turn cause the behaviour.
*The COMT gene regulates the production of the neurotransmitter dopamine. It produces lower levels of catechal-O-methythransferase and therefore higher levels of dopamine.
*The SERT gene affects the transport of serotonin and is involved in creating lower levels of the neurotransmitter. This in turn would begin the behaviour of OCD.
What is meant by the diathesis stress model?
Diathesis stress model suggests that we are genetically predisposed to attain a behaviour however, an environmental stimuli will cause the actual onset of this disorder. The genetic increases our chance of attaining disorder but something causes the actual onset.
Billet et al (1998) did a meta-analysis of twin studies that had been carried out over a long period of time. They found that in MZ twins, if 1 had OCD, the other had it 68% of the time. However, this was 31% in DZ twins.
Outline Biological structures as an explanation for treating OCD
D’Astous et al (2013) evaluated a procedure called bilateral anterior capsulotomy (surgical damage to part of the basal ganglia call the internal capsules). In a 7 year follow up, almost half of 19 patients had responded well to surgery however, two had permanent complications as a result of surgery. This suggests that this area of the brain must play a role in OCD as a change in this area impacted patients behaviour.
Strengths of Biological explanations of OCD
*Research to support from Billet et al (1998) who found the occurrence of OCD in MZ twins was greater than DZ twins suggesting there must be a genetic influence on OCD.
*Research to support from D’Astous et al (2013) who found that patients responded well to surgery suggesting that this area of the brain must play a role in OCD as a change in this area impacted patient’s behaviour.
*Success of drug therapy shows that there must be a biological basis of behaviour as it is clearly effective in treating the behaviour meaning there must be a biological basis.
Limitations of biological explanations of OCD
*Changes in neurochemistry could be the result of the behaviour rather than the cause meaning that we cannot be sure what the actual cause of OCD may be.
*Drug treatments are only effective 50% of the time so therefore the cause may be something alternative to biological or additional to.
*Evidence sometimes only relates to the cause of the compulsions and not the obsessions or vice-versa meaning it does not fully explain the disorder.
*Concordance rates are never 100% therefore we cannot say it is definitely down to genetics and environment factors must play a part.
*This idea neglects other approaches as the cognitive approach would suggest that irrational thoughts are the cause of this behaviour. Arguably, obsessions are caused by unhealthy and irrational thoughts and expectations and compulsions are behaviours we exhibit to deal with this.
Outline the main biological treatments for OCD
Anti Depressants - SSRIs
Antidepressants - tricyclics
Anti - anxiety drugs
Other drugs
Outline the functions of SSRIs
Low levels of serotonin are associated with depression - these are associated with the worry circuit. These work by blocking the re uptake of serotonin at the synapse therefore increasing the serotonin concentration at receptor cites.
Outline the function of tricyclics
Low levels of serotonin are associated with depression - these are associated with the worry circuit. Tricyclics work similarly to SSRIs however, tricyclics work by blocking the reabsorption of serotonin and noradrenaline after it has fired.
Outline the function of anti anxiety drugs
Benzodiazapines are commonly used to reduce anxiety. They slow down neurotransmission through enhancing the activity of GABA. GABA is a neurotransmitter that quietens the effect of neurons in the brain. It locks to receptor cites and it increases the flow of chloride ions into the neuron which makes it harder for that neuron to be stimulated.
What are the functions of other drugs?
D-Cycloserine is an anti-biotic that is used to treat tuberculosis. This enhances the transmission of GABA which in turn will reduce anxiety.
Outline Koran et al (2000)
Aims: To investigate whether multiple drugs to treat OCD would be more effective in treating non-responsive forms of OCD.
Procedure: Ten patients who had not responded to 10 weeks of treatment with the SSRI antidepressant fluoxetine who had all been diagnosed with OCD for the last year. Treatment continued however, another drug olanzapine was also given for an additional period of 8 weeks.
Findings: The mean OCD symptom scores dropped by 16% with one patient showing a 68% improvement.
Conclusion: This suggests that giving simultaneous drug therapies can be more effective that single drug therapy meaning the cause may be biological.
Strengths of Biological treatments
*Supporting research from Hollon, Koran and Soomro et al on effectiveness of drugs as they show the effectiveness of drug treatments in treating OCD.
*Drugs are a cheaper option compared to therapies that are easy to administer for the patient meaning that they are economically accessible and easier for the patient to engage with.
Limitations of Biological treatments of OCD
*Drugs can have side effects that cause patients to stop taking them thus returning to the disorder.
*Drugs are palliative as they only treat the symptoms unlike psychological therapy. When people stop taking the drugs, they have a high chance of relapse.
*Taking drugs reinforces the idea to those patients that they have a disorder meaning it may reinforce their disorder.
*People may become dependent on the drugs for their treatment and be stuck on them for the rest of their life meaning they may not actually treat their disorder.
*This is a nomothetic treatment meaning all patients receive the same treatment which is not good as people have different obsessions therefore should have different treatments
