Biological Apporach To OCD Flashcards
What is the main theory
Ocd is caused by neural abnormalities in the structure or function of the brain
What does the biological approach consist of
NAGI
Neural abnormalities, genes, illness
What is the abnormality in the loop of basal ganglia and orbito frontal cortex
Over activity of direct pathway that triggers concerns about danger
Under activity of indirect pathway which inhibits compulsive behaviour
What are neurotransmitters
Chemicals in the brain that allow messages to be sent between Brain cells
How are neurotransmitters linked to OCD
Mutations in genes linked to activity of neurotransmitter serotonin has been found in patients with ocd.
- medicines that increase serotonin decrease symptoms of OCD
Describe baxters study
Patients who had treatment of SSRI’s or CBT found they were both as effective so the brain abnormality could be a consequence not a cause if therapy managed to treat it as well as serotonin
evaluate the biological approach
Can’t be sure of cause and effect between neutral abnormalities and ocd
Describe polaks study
Study of a man who had a heart attack and suffered brain damage to his basal ganglia - brain starved of oxygen
Showed compulsive whistling behaviour which worsened when he was tired
Describe nestadt’s study - twins
Found the MZ concordance rate of OCD was 68% while DZ was 31%
So there must be a genetic explanation, but it is not 100% so other factors must also effect it
Describe van grootheest
19 studies of 10,000 twins
Found that OCD is developed more strongly if developed in childhood than in adult hood, so environmental triggers can cause adults to have OCD
What are SSRIS
specific serotonin uptake inhibitors
Give details of how serotonin is given
20mg a day 3-4 months gradually stopped GP or Psychologist Side effects - irritability Sleep disturbances Headaches Suicidal thoughts
How does SSRI’s reduce OCD
Stays in synaptic gap for longer so that the orbito frontal cortex could function normally and stop compulsions
Describe korans study
Added olanzapine to lower dopamine levels
Mean score on Yale brown obsessive compulsive scale was 29
Dropped to 24
:(- 2/3 of patients put on weight
Small sample + no placebo
Evaluate the appropriateness of SSRIS
Unpleasant side effects
Brings a small symptom reduction even if it doesn’t completely treat it so people can carry on with jobs which helps the economy