psychopathology - OCD Flashcards
what are behavioural characteristics of OCD
compulsive behaviour which is repetitive for example washing hands
Avoidance of situtaions that trigger anxiety
emotional characteristics of OCD
Unpleasent, intense anxious thoughts
Guilt and disgust
depression
cognitive characteristics of OCD
Insight
cognitive stratergies to manage anxiety
obsessive thoughts
what is the process of OCD?
obssesive though -> anxiety -> compulsive behaviour -> temporary relief -> repeat
what is the basis of genetic explanations?
Genes make up chromosomes and consist of DNA which codes our physiological and psychological features. This is transmitted from parent to offspring.
what is the genetic explanation for OCD?
- Genes are involved in individual vulnerability to OCD.
- Lewis observed that of his OCD patients 37 had parents with OCD.
- Candidate genes- 230 Genes have been identified to cause OCD.
- polygenic.
- aetiologically heterogenous.
What does aetiologically heterogenous mean?
when one gene cause a disorder in one person but another gene cause the same disorder in a different person
what is the basis of neurological explanations?
Neurologists hold the view that physical and psychological characteristics are determined by the behaviour of nervous system, the brain.
what is the neural explanation of OCD?
Genes associated with OCD are likely to effect key neurotransmitters. For example, serotonin which is believed to help regulate mood. If a person has low serotonin levels, then normal levels of transmission do not take place, so mood is affected SUCH THAT THEYRE MORE ANXCIOUS
Also, a part of neural explanation- how is impaired decision making associated with OCD?
Some OCD is associated with impaired decision making. This can be associated with abnormal activity in the lateral frontal lobes which are responsible for logical thinking. The area parahippocampul gyrus is also associated with the process of unpleasant emotions in OCD.
what part of the brain is responsible for logical thinking
lateral frontal lobes
what part of the brain is responsible for unpleasant emotions?
parahippocampul gyrus
what neurotransmitter regulates mood and is linked to OCD
serotonin
What does SSRI stand for?
selective serotonin reuptake inhibitor
How do SSRIs work?
standard treatment for OCD. Serotonin is released by specific neurons in the brain. The neurotransmitters is released from pre-synaptic neuron and travels across the synapse to bind to the receptor sites on the post-synaptic neuron. It is then reabsorbed by the pre-synaptic neuron where it broken down to be reused. The SSRIs prevent the re-absorption of serotonin increasing its levels in the synapse and continuing to stimulate post-synaptic neuron. This increases serotonin levels and thus mood.
what is the standard daily does of drug teatment for OCD?
20g of fluoxetine
how long does it take for SSRIs begin to be effective?
it usually takes 3-4 months to become effective
what are SNRIs?
Serotonin-noradrenaline reuptake inhibitor - These are for people who don’t respond to SSRIs it increases serotonin and noradrenaline.
what is the older anti-depressant and why don’t we use it?
Tricyclics - has more side-effects- last resort
what are the strengths of the genetic explanation for OCD?
- Research support- Nestadt reviewed twin studies and found that 68% of twins shared OCD as opposed to 31% of non-identical. Suggests a genetic influence.
- Research support – Lewis 37% of his OCD patients had parents with OCD.
what are the weaknesses of the genetic explanation for OCD?
- There is up to 230 candidate genes for OCD this reduces predictive validity because we cannot be sure that one gene will ensue a person has OCD. Less useful.
deterministic
reductionist
Evaluate the neural explanation for OCD?
- There is a problem with causation. Whilst we have found that patients with OCD have lower serotonin levels this is a correlation. We cannot be sure this causes OCD or OCD causes this limit of serotonin.
- Practical application – Drug therapy. Because we know low serotonin levels is linked with OCD, we can help people live with it by increasing serotonin uptake in the synapses.
- deterministic
- REDUCTIONIST
general limitations of biological approach to OCD?
- Cromer found that over half of OCD patients had a traumatic event suggesting environmental factors have a roll in OCD.
- Biologically Reductionist- reduces people to biology when environmental factors can also have a role
strengths of drug therapy?
- Evidence for effectiveness in improving lives. Soomro reviewed studies comparing placebos to SSRIs and concluded that all 17 had better results in SSRIs. Symptoms decline in 70% of people taking drug.
- Cheap and not disruptive of life
weaknesses of drug therapy?
- Can have side effects – low libido, blurred vision, and indigestion. Extreme side effects can be weight change tremors. This decreases effectiveness because people stop taking them.
- Drug therapy cannot be treatment for all people since trauma can also caused OCD.
- Unreliable evidence for OCD by biased drug companies
