OCD pt1 Flashcards
What are the 3 categories of the characteristics of OCD?
-Behavioural category
-Emotional category
-Cognitive category
What are the 2 types of characteristics in the behavioural category?
Explain
-Repetitive compulsions: sufferers feel compelled to repeat a certain behavior e.g. hand washing
-Avoidance: Keeping away from situations that trigger their compulsions e.g. hand washers avoid coming into contact with germs
What are the 4 types of characteristics in the emotional category?
Explain
-Accompanying depression: OCD is often accompanied with depression e.g. low mood and lack of enjoyment can appear
-Anxiety and distress: unpleasant state of high arousal caused by the urge to repeat a behaviour
-Disgust: in themselves for performing their compulsions
-Guilt: directed at themselves
What are the 3 types of characteristics in the cognitive category?
Explain
-Obsessive thoughts: unpleasant thoughts that occur over and over again
-Cognitive strategies to deal with obsessions: sufferers adopt coping strategies that can distract them from everyday life e.g. religious person tormented by guilt may respond by praying
-Insight: sufferers are aware their obsessions and compulsions are not rational
What do genetic explanations look at?
How disorders can be passed on from parents to offspring through our genes (chromosomes that consist of DNA that codes the characteristic of an organism).
What does genetic vulnerability mean?
People gain a vulnrebility through genes, but an environmental stressor is also required -‘The diathesis-stress model’
What are the 4 genetic explanations about OCD?
-OCD is inherited and passed on through family
-OCD involves candidate genes
-OCD is polygenic
-OCD is aetiologically hetrogeneous
What does candidate genes mean? E.g? (2)
Specific genes which create vulnerability for OCD
e.g. SERT and COMT
What does polygenic mean?
How many genes did Taylor predict were involved in OCD?
Poly=many
OCD is NOT caused by one single gene, but several genes are involved
230
What does aetiogically hetrogeneous mean?
Hetro=diverse in character
Aetiology=the cause, set of causes, or manner of causation of a disease or condition
What is a strength of the biological explanation? PET -family studies
P: there is research support from family studies
E: Lewis examined patients with OCD
Found that 37% of the patients with OCD had parents with the disorder and 21% had siblings who suffered.
T: supports the genetic explanation, it appears individuals are inheriting their OCD from parents.
What does concordance rate mean?
Monozygotic twins do not always have 100% concordance rate, what does this suggest?
-Similarity
-OCD can’t always be genetic
If one monozygotic (100% shared DNA) twin had OCD, would you expect the other twin to have OCD?
If one dizygotic (50% shared DNA) twin had OCD, would you expect the other twin to have OCD?
-Yes
-50% chance
What is a strength of the biological explanation? PET -twin studies
P: there is research support from twin studies
E: Nestadt et all showed 68% of monozygotic twins were both diagnosed with OCD, compared to 31% of dizygotic twins
T: therefore supports the geenetic explanation for OCD as twins who share 100% of DNA were more likely to both have OCD than twins who only share 50% of DNA
Do twins only share the same environment? Why?
No , they also share the same environment e.g. house, parents
What did Cromer find that offers an alternative explanation for OCD?
-Found that over 50% of the OCD patients in their sample has experienced a traumatic event in their past
-OCD was more severe in those with more than one trauma
-Stressful situations in the environment>OCD
What does the diathesis-stress model state?
What is a stength of this?
-Mental illness occurs due to an interaction between genes and the environment
-Holistic
What is a weakness of the genetic explanation of OCD? PET -candidate genes
P: too many candidate genes
E: Taylor found there were over 230 candidate genes involved with OCD>finding a definitive genetic cause is very unlikely
T: decreases the usefulness of this explanation as it has low predictive validity, we cannot predict who will/won’t develop OCD based on their genes.
What are neural explanations concerned with?
How brain structures and neurotransmitters affect OCD
What is the usual function of the left parahippocampal gyrus?
What is it’s function in OCD patients? e.g?
-Regulating unpleasant emotions
-Increases processing of unpleasant emotions, e.g. guilt
What is the usual function of the frontal lobe?
What is it’s function in OCD patients? e.g?
-Motor skills, decision making, problem-solving
-Impaired decision-making e.g. compulsion
What is the usual function of serationin?
What is it’s function in OCD patients?
-Regulating mood
-Reduced seratonin in the synapse>can’t regulate mood>OCD
What is the usual function of dopamine?
What is it’s function in OCD patients?
-Reward motivated behaviour
-Excessive dopamine in the synapse>OCD
What are seratonin and dopamine both?
Neurotransmitters
What is a weakness of the neural explanation for OCD? PET -causation
P: cause and effect cannot be established
E: changes in the brain are a result of OCD or vv AND changes in levels of serotonin and dopamine are a result of OCD or vv
T: causation cannot be implied, as only association exists, decreasing the usefulness of the theory
What does comorbidity mean?
Where 2 conditions exist at the same time
What is a weakness of the neural explanation for OCD? PET -comorbidity
P: serotonin-OCD link may simply be due to comorbidity with depression
E: there is evidence that most people who suffer from OCD also suffer from depression, the depression is most likely due to the disruption of the serotonin system
T: serotonin-OCD link may actually be due to the depression patients experience, alongside OCD, not just OCD alone
How do we treat OCD?
(real world application)
Drug therapy
What is a strength of the biological explanation? PET -real world application
P: this explanation has been translated into a successful treatment
E: based on the knowledge that serotonin causes OCD, SSRIs have been developed
T: SSRIs benefit the patient and economy
What is a counter-point to the real world application of drug therapy? (3)
-Improvement rates from the use of drugs are only at 50%
-There must be other causes of OCD other than a lack of serotonin
-If it was just serotonin, we would expect 100%
