OCD Flashcards
define OCD
defined by obsessions - constant intrusive thoughts that cause high anxiety and compulsions - behavioural response to deal with invasive thought process
what are the behavioural characteristics of OCD?
compulsions
avoidance behaviour
behavioural characteristics of OCD: compulsions
repetitive and intrusive thoughts focused around the stimulus which reduce anxiety through being a method of acting upon obsessive thoughts
behavioural characteristics of OCD: avoidance behaviour
negatively reinforced through classical conditioning
individual who avoids the specific stimulus will avoid the anxiety associated with having to carry out compulsive behaviours and suffer from obsessive thoughts
may lead to social withdrawal if going out triggers obsessions and compulsions
what are the emotional characteristics of OCD?
guilt and disgust
depression
anxiety
emotional characteristic of OCD: guilt and disgust
feelings of guilt and disgust
emotional characteristic of OCD: depression
due to the constant compulsion to carry out compulsive/repetitive behaviours which often interfere with day to day functioning and relationships
emotional characteristic of OCD: anxiety
associated with the acknowledgement that the obsessive thoughts are irrational, but despair at the fact that they will always lead to compulsive behaviours
what are the cognitive characteristics of OCD?
obsessions
hypervigilance
selective attention
cognitive characteristics of OCD: obsessions
intrusive, irrational, recurrent thoughts lead to unpleasant, catastrophic thoughts about potential danger
cognitive characteristics of OCD: hypervigilance
permanent state of alertness
constantly looking for source of obsessive thoughts
cognitive characteristics of OCD: selective attention
constant focus on objects connected to obsession so much they cannot focus on other things in environment or conversations
biological approach to explaining OCD
diathesis-stress model suggests that some have a genetic vulnerability towards developing depression - Lewis et al
OCD is polygenic and is associated with the functioning of neurotransmitters involved in regulating mood
explain the genetic explanation of OCD
its thought a predisposition to OCD is inherited from parents
researchers identified candidate genes which increase a person’s vulnerability towards developing OCD by influencing the functioning of neural systems in the brain e.g. the SERT gene affects reuptake in the serotonin system and 5HT1-D beta
OCD is polygenic so a predisposition to OCD requires a range of genetic changes
explain the neural explanation of OCD - serotonin
low serotonin levels are thought to cause obsessive thoughts as reuptake happens too quickly so there are low levels of serotonin in the synapse
the SERT gene is responsible for serotonin transportation in the synapse
explain the neural explanation for OCD - neural structures
if the basal ganglia is hyperactive, this allows minor worries from the orbitofrontal cortex to get to the thalamus and back to the OFC causing a loop of recurring obsessive thoughts which damages the rational decision making part of the brain
strengths of the diathesis-stress model
supporting evidence - Nestadt et al found that 68% of identical twins share OCD compared to 31% of non-identical twins
suggesting there is a genetic basis for this disease
weaknesses of the diathesis-stress model
too many candidate genes - difficult to assess which candidate genes have the greatest influence and so which genes drug treatments should target
ignores environmental factors - Cromer et al found that over half of OCD patients experienced trauma that triggered their OCD
the biological approach to treating OCD
selective serotonin reuptake inhibitors (SSRIs) act on the serotonin system by preventing the reuptake and breaking down of serotonin by the presynaptic neuron. thus, the concentration of serotonin within the synapse increases, causing the post-synaptic neuron to be continually stimulated
tricyclics have a similar effect but are reserved for those who do not respond well to SSRIs. selective noradrenaline-reuptake inhibitors (SNRIs) increase the concentration of the noradrenaline neurotransmitter in the brain
strengths of drug therapy
cost-benefit analysis - increased knowledge about the effectiveness of certain drug treatments for OCD and cognitive treatments can reduce the time people take off sick increasing the productivity of the workforce - cost-effectiveness of treatments of OCD can help save the NHS money
cost-effective and non-disruptive
cheap compared to other treatments
patients can lead a normal life
weaknesses of drug therapy
serious side effect - e.g. increased heart rate and aggressiveness which can have serious implications to everyday life
obsession
a persistent thought, idea, impulse or image that experienced repeatedly, feels intrusive and causes anxiety
compulsion
a repetitive and rigid behaviour or mental act that a person feels driven to perform in order to prevent or reduce anxiety
DSM recognised disorders
OCD - characterised by obsessions and/or compulsions
trichotillomania - compulsive hair pulling
hoarding disorder - the compulsive gathering of possessions and the inability to part with anything regardless of its value
excoriation disorder - compulsive skin picking
main symptoms of OCD according to the DSM
- Recurrent obsessions and compulsions
- Recognition by the individual that the obsessions and compulsions are excessive and/or unreasonable
- That the person is distressed or impaired, and daily life is disrupted by the obsessions and compulsions
the OCD cycle
obsessive thought –> anxiety –> compulsion –> temporary relief
strengths of the biological approach as an explanation for OCD
+ GENETIC EXPLANATION: Nestadt - family and twin studies support idea of heritability of OCD - the more closely genetically related 2 people are, the higher the concordance e.g. MZ twins have a 68% concordance rate, DZ twins have a 31% concordance rate, 1st-degree relatives have 10% concordance rate = suggests a predisposition to OCD is inherited
+ NEURAL EXPLANATION: PET scans show hyperactivity in the OFC in people with OCD supports theory HOWEVER cannot be sure if hyperactivity is a cause or consequence of OCD
weaknesses of the biological approach as an explanation for OCD
- correlation may not mean causation - other factors may be at play such as growing up in similar environments, treated in a similar way etc - biologically deterministic
- diathesis-stress response more valid explanation - inherit a genetic vulnerability that may be triggered by a traumatic life experience which increases severity of symptoms
- Soomro meta-analysis demonstrated SSRIs are more effective than placebos suggests bio aspect to OCD but results argue that low serotonin levels have a role to play in OCD but are not the sole cause
drug therapy to treat OCD
SSRIs select serotonin in the brain and inhibit the reuptake process in the synapse so serotonin is still present in the synaptic cleft and continues to stimulate the postsynaptic neurone - decreases anxiety
SSRIs take 3-4months to work and are sometimes ineffective
other types of drug therapy to treat OCD
benzodiazephine - enhance GABA to slow the CNS and results in relaxation
SNRIs - increase serotonin and noradrenaline in a similar way to SSRIs - alternative to SSRIs but have more severe side effects
strengths of drug therapy to treat OCD
+ Soomro’s meta-analysis found that SSRIs reduced symptoms of OCD significantly compared to placebos - effective in short-term
+ Soomro’s meta-analysis was large-scale - results were valid due to large sample size
+ drug therapy is inexpensive and convenient compared to other therapies - real-world application as NHS is more likely to prescribe drug therapy rather than CBT
weaknesses of drug therapy to treat OCD
- most research studies on drug therapies are conducted by pharmaceutical companies which have a vested financial interest in showing the drugs are effective - results may suffer from researcher bias
- drug therapies have side effects e.g. nausea, headaches etc - CBT preferred
- drug therapies take longer to cause a symptom reduction - patient may become dependent on drugs - CBT preferred
- drug therapy usually short-term solution
