OCD Flashcards
define OCD
anxiety disorder characterised by obsessive thinking and repetitive behaviour
behavioural characteristics of OCD
- compulsions are repetitive, e.g., counting, tidying/ordering objects into groups
- anxiety-reducing compulsions = manage anxiety from obsessive thoughts, e.g., excessive hand washing in response to obsessive fear of germs
- avoidance of triggering situations
emotional characteristics of OCD
- anxiety/distress
- accompanying depression
- guilt/disgust
cognitive characteristics of OCD
- obsessive thoughts (recurring, intrusive, unwanted)
- awareness of irrationality of thoughts
- use of cognitive coping strategies to deal with obsessions (may appear abnormal to onlooker)
biological approach to explaining OCD: genetic
- OCD is polygenic (caused by combo of genetic variations together significantly increasing vunerability) = up to 230 (Taylor)
- identification of candidate genes that can create vunerability for OCD; COMT & SERT (neurotransmitters)
- OCD is aetiologically heterogenous (diff group of genes cause OCD in diff people)
pros of genetic explanation of OCD
RESEARCH SUPPORT
Nedast’s Twin Studies = 68% shared in MZ vs 31% in DZ twins
Marini and Stebnicki = 4x more likely to develop if family member has been diagnosed
= support link between genetic make-up and vunerability to OCD
cons of genetic explanation of OCD
ENVIRONMENTAL FACTORS
= influence of environmental risk factors
= OCD not entirely genetic
- Cromer found over 1/2 of OCD patients in sample experienced past traumatic event
OCD = more severe in those with 1 or more traumas
- Diathesis Stress Model
= genetics is only partial explanation
biological approach to explaining OCD: neural (decision-making systems)
- hoarding disorder (particular case of OCD)
= associated with impaired decision-making:
- abnormal functioning of lateral frontal lobe (logical thinking/decision making)
- poor processing of unpleasant emotions = abnormality in left parahippocampal gyrus
biological approach to explaining OCD: neural (SERT/COMT)
- mutation in SERT (neurotransmitter for serotonin) = causes increased reuptake into neuron = impact mood-regulating behaviour
- mutation in COMT (neurotransmitter for DA) = causes high DA levels = lead to feelings of anxiety, disorganised thinking and can influence concentration = explain obsessions
pros of neural explanation of OCD
RESEARCH SUPPORT
- effective reduction in symptoms through use of antidepressants working on serotonin = support involvement
- conditions with biological origin (Parkinson’s Disease) include OCD symptoms = assume biological processes must also underly OCD
= support influence of biological factors in OCD
cons of neural explanation of OCD
CO-MORBIDITY
= many people with OCD also experience clinical depression, which also involves disrupted serotonin action
- means serotonin may not be relevant to OCD symptoms (may just be because depressed)
What is the biological approach to treating OCD
= drug therapy to increase serotonin levels in brain (reduce reuptake)
SSRIs, e.g., Prozac = prevent reabsorption and breakdown on serotonin = increase levels in synapse and continue stimulation of POST SN
20mg avg. daily dose, 3-4 months for effectiveness
- can be used alongside therapy = engage more effectively due to drugs reducing emotional symptoms
Alternatives to SSRIs
if SSRIs ineffective
= Tricyclics (e.g., clomipramine), more severe side effects
= SNRIs, increase serotonin and noradrenaline levels
Pros of biological approach to treating OCD
EVIDENCE FOR EFFECTIVENESS
= for SSRIs reducing symptom severity and improving quality of life in around 70%
- Soomro et al = 17 studies comparing SSRI to placebo = significantly better outcomes for SSRI
= display that they are helpful in most cases
further strength of biological approach to treating OCD
COST EFFECTIVE/NON-DISRUPTIVE
= drugs cheaper compared to psychological treatments = more accessible
= good value for public health systems
- non-disruptive (no time spent attending therapy sessions)
= drugs are popular with many
Cons of biological approach to treating OCD
SERIOUS SIDE EFFECTS
- Some experience; indigestion, blurred vision, loss of sex drive = usually short term but distressing
- more common with tricyclics
= means some people have reduced quality of life due to drugs, stop taking altogether = cease to be effective
Role of serotonin and dopamine
Serotonin = regulate mood, lower levels = associated with mood disorders, e,g., depression
Dopamine = help control impulses, emotional responses
