OCD Flashcards
What does OCD stand for?
Obsessive Compulsive Disorder
Behavioural characteristics of OCD
Avoidance
Compulsions are repetitive
Compulsions reduce anxiety
Emotional characteristics of OCD
Anxiety and distress
Disgust
Accompanying depression
Cognitive characteristics of OCD
Obsessive thoughts
cognitive coping strategies
insight into excessive anxiety
What genes are involved in the development of OCD
SERT gene (serotonin regulatory gene)
COMT gene (regulating the production of dopamine)
Cognitive characteristics of OCD
Obsessive thoughts
Cognitive coping strategies
Insights into excessive anxiety
As there are multiple genes involved in OCD what does this mean?
OCD is polygenic
How does the SERT gene affect OCD
If the SERT gene is faulty it causes transportation issues and so lower levels of serotonin that impacts OCD like symptoms
How does the COMT gene affect OCD
this gene is responsible for the enzyme that breaks down dopamine and when there is a mutation it stops this process = higher levels of dopamine
What is the diathesis stress model?
That environmental stressors trigger certain genes to influence OCD.
Strengths of the genetic explanation?
Nestadt found that 68% of MZ twins had OCD compared to 31% of DZ twins
Weaknesses of genetic explanation of OCD
There are many environmental risks involved in OCD - Cromer found that half of his sample with OCD had gone through trauma in their past suggesting environmental factors affect OCD development rather than being truly genetic in nature.
What areas of the brain are involved in the neural explanations for OCD
Caudate nucleus
Orbital frontal cortex (OFC)
What is the neural explanation for OCD?
The OFC sends a worry signal and the caudate nucleus switches this off. When the SERT and COMT gene are compromised they cause the OFC to send too many worry signals (too much dopamine) and the caudate nucleus cannot send turn it off (because of low levels of serotonin).
Strengths of neural explanation for OCD
Development of treatments such as SSRIs
Weaknesses of neural explanation for OCD
All evidence for neural explanations are simply correlational which has no causation between neurochemicals and OCD
What treatment is used for OCD
SSRIs (Selective serotonin reuptake inhibitors)
How do SSRIs work?
They block the reuptake of serotonin on the pre synaptic cell allowing the serotonin to bind to receptors on the post synaptic cell. This usually leads to the chemical message being passed on to help the caudate nucleus switch off the worry circuit.
Strength of SSRIs
Soomro - symptoms reduce 70% when using SSRIs
Weakness of SSRIs
Side effects
What other treatments other than SSRIs can be used to treat OCD
Tricyclics (blocks the transport mechanism that reabsorbs serotonin) and benzodiazepines that slows down activity in the central nervous system by enhancing GABA activity (GABA produces a calming affect)