Psychopathology Flashcards
(25 cards)
Briefly outline the genetic explanation of OCD
It suggests that OCD is inherited and that specific genes cause it.
What does the COMT gene do?
It regulates dopamine. A variation of this gene results in higher levels which is more common in OCD patients
What does the SERT gene do?
It affects the transport of serotonin, causing lower levels of serotonin
Briefly outline the neural explanation of OCD
It focuses on neurotransmitters and structures of the brain. It suggests that abnormal levels of serotonin and dopamine, as well as the basal and orbitofrontal cortex, are implicated in OCD
How does research support the role of serotonin in OCD?
When examining anti-depressants, it was found that drugs which increase serotonin are effective in treating OCD patients,
How does high dopamine levels affect OCD patients?
It is associated with symptoms like compulsive behaviours
What does the basal ganglia do?
It is involved in coordination of movement
What do head injuries in the basal ganglia do?
It develops OCD-like symptoms
What did Max et al. found?- OCD
When the basal ganglia is disconnected from the frontal cortex during surgery, OCD-like symptoms are reduced.
What does the orbitofrontal cortex do?
It converts sensory info into thoughts and actions
What have PET scans found with higher activity in the orbitofrontal cortex?
It is more common in OCD patients. This may be dur to the increased conversion of sensory info to actions which results in compulsions. This prevents them from stopping their behaviour.
Evaluate of the genetic explanation of OCD
- S: Research support for the vulnerability to OCD due to genes. One source is twin studies (Nestadt et al.) Another is family studies (Marini and Stebnicki)
- L: Environmental risk factors are involved. Crorner et al. found that over half of OCD patients in their sample had a traumatic event in their past.
What did Nestadt et al. find?
Reviewed twin studies. Found that 68% of MZ twins shared OCD compared to 31% of DZ twins
What did Marini and Stebnicki find?
A person with a family emmer with OCD is around 4X more likely to develop it.
Evaluate the neural explanation of OCD?
- S: Antidepressants that work on serotonin reduce symptoms. Also, symptoms form parts of biological conditions like Parkinson’s disease that causes muscle tremors/paralysis (Nestadt et al.)
- L:The serotonin-OCD link isn’t unique to OCD. Many OCD patients have depression which affects serotonin action.
What is co-morbidity?
When someone has 2 disorders together
What are 2 biological treatments for OCD?
Anti-depressant and Anti-anxiety drugs
How do SSRIs work?
When serotonin is released from the pre-synaptic cell into the synapse, it travels to the receptor sites on the post-synaptic neuron. Serotonin not absorbed into the post neuron is reabsorbed into the pre neuron. SSRIs increase serotonin in the synapse by preventing the reabsorption. This increases levels in the synapse and the post neuron.
What is the daily dosage of the SSRI fluoexetine?
20mg but can be increased if not benefitting the person.
How long does it take for SSRIs to work?
After about 3-4 months of daily usage
Why are drugs usually combined with CBT to treat OCD?
The drugs reduce emotional symptoms like anxiety or depression so OCD patients can engage more effectively in CBT
What are benzodiazepines?
A range of anti-anxiety drugs e.g. Valium and Diazepam. They work by enhancing the action of the neurotransmitter GABA.
What does GABA do?
It tells the neurons in the brain to ‘slow down’ and stop firing. Around 40% of neurons in the brain respond to it. BZs have a quietening effect on the brain, reducing anxiety and obsessive thoughts.
Evaluate the biological treatment of OCD- strengths
- SSRIs reduce symptoms and improve quality of life. Mustafa et al. studied 17 studies that compared SSRIs with placebos + found SSRIs to be more effective.
- Drugs are cost-effective and non-disruptive to people’s lives. 1000s of drugs can be made in the time of one session of therapy.
