Psychopathology - OCD Flashcards
What it is, biological explanations and treatments
What is the cycle of OCD?
obsessive thoughts lead to anxiety, anxiety leads to compulsive behaviour, complusive behaviour leads to temporary relief, which then leads to another obsessive thought
What is OCD?
obsessive compulsive disorder.
many different types
What is an obsession?
recurring unwanted or intrusive thoughts that cause distress
What is a compulsion?
repetitive mental or physical act that provides temporary relief to the sufferer
What are the behavioural characteristics of OCD?
compulsions, avoidance
What are the cognitive characteristics of OCD?
obsessive thoughts, cognitive coping strategies, awareness of irrational thought process
What are emotional characteristics of OCD?
guilt, disgust, anxiety, depression, distress
What is a gene?
section of DNA that codes for characteristics
Lewis (1936)
37% of OCD patients had a parent with OCD
21% had a sibling with OCD
Diathesis-stress model
genes make an individual more likely to suffer from a disorder but environmental stress is necessary to trigger it
Candidate genes
create vulnerability for OCD (5HT1-D)
some of these genes are involved in regulating development of serotonin system
Synapse
where neurons connect and communicate (tiny gaps)
Taylor (2013)
230 genes are involved in OCD
neurotransmitters that regulate mood and involved with action of dopamine and serotonin
polygenic
there is not only one definite OCD genes, many working together increase vulnerability
aetiologically heterogeneous
one group of genes might cause OCD in one person but different group could cause it in another
strengths of genetic explanations of OCD
+ supporting evidence from twin studies
Nastadt et al (2010)
68% identical twins shared OCD
31% non-identical twins shared OCD
limitations of genetic explanations of OCD
- twin studies used
identical and non-identical twins have different experiences - candidate genes
too many, unclear. need more research and depth to know if someone will have a vulnerability - environmental risk factors
Cromer et al (2007)
50% of OCD patients experienced traumatic event and OCD was found to be more severe after a traumatic event which shows OCD isn’t entirely genetic
what does low serotonin mean?
no normal mood regulation
what parts of the brain perform abnormally in OCD patients?
lateral frontal lobe = decision making and logical thinking
parahippocampal gyrus = processing unpleasant emotions
worry circuit - basal ganglia
evaluation of neural explanations of OCD
+ supporting evidence -> antidepressants work to treat OCD
- unclear which neural mechanisms are involved, no brain systems are definitely linked to OCD.
- co-morbidity with depression, unclear if low serotonin levels are due to OCD or depression
- cause and effect
do brain abnormalities cause OCD or does OCD cause brain abnormalities
what is the main treatment for OCD?
drug therapies which increase or decrease levels of neurotransmitters
which is the main drug used to treat OCD?
SSRIs.
increases levels of serotonin in brain and stops serotonin being reabsorbed by the neuron.
3-4 months before effects kick in
different dosage for different patients
ideally used alongside CBT
what are alternatives to SSRIs
- tricylics
more severe side effects (leading to more attrition)
increases serotonin - SNRIs
increases serotonin and noradrenaline
only been used for last 5 years
attrition
giving up on a therapy
what are the strengths of biological treatments of OCD?
+ cheaper, quicker and easier than other treatments
+ effective
Soomro et al (2009)
compared placebo to antidepressants
better results for SSRI patients
better when combined with CBT
symptoms decline for 70% of patients on SSRIs
limitations of biological treatments of OCD
- unreliable evidence
drug companies publish results so they could be hiding negative results (publication bias) - side effects
usually temporary and for a minority but more side effects means more attrition - not most effective treatment
Skapinakis et al said cognitive and behavioural therapies are more effective than biological in treating OCD