Obsessive compulsive disorder (OCD) Flashcards
what are obsessions?
persistent, intrusive, recurring thoughts or images
- 10% of sufferers suffer with just obsessions
what are compulsions?
repetitive, ritualistic behaviour e.g. hoarding, excessive washing etc.
- 20% of sufferers suffer with just compulsions
percentage of sufferers who suffer with obsessions + compulsions?
70%
- 1 in 50 people have OCD (suggests its a biological cause)
what are the DSM-5 categories of OCD?
- Trichotillomania- compulsive hair pulling
- Hoarding disorder- compulsive gathering of possessions + the inability to part with anything regardless of its value
- Excoriation disorder- compulsive skin picking
behavioural characteristics of OCD?
- compulsions are repetitive- sufferers feel compelled to repeat behaviour e.g. hand washing
- compulsions reduce anxiety
- avoidance- avoid situations which may trigger their obsessive thoughts + compulsive behaviours
emotional characteristics of OCD?
- Anxiety +distress- obsessive thoughts can be frightening + overwhelming, urge to repeat behaviour creates anxiety
- accompanying depression- feel trapped by obsessions + compulsions etc
- guilt + disgust- irrational guilt due to neglecting friends etc or disgust towards external object or self
cognitive characteristics of OCD?
- obsessive thoughts
- cognitive coping strategies- helps manage anxiety but makes them appear abnormal + distracts them from everyday tasks
- insight into excessive anxiety- aware obsessions + compulsions aren’t rational. Catastrophising thoughts about worst case scenarios that could occur if anxieties were justified e.g. ‘I may die if I don’t wash my hands’. Hypervigilant + focus on potential hazards
what approach explains OCD?
biological
what does genetic explanation of OCD assume?
- assumes OCD is inherited via genes across family generations
genetic explanation research support?
- research support from family + twin studies
–> often compare MZ twins + DZ twins for a particular trait –> if trait has a biological basis= expect higher concordance rate between MZ twins than DZ twins as they’re genetically identical –> BUT we never get 100% concordance rate
genetic explanation what do biopsychologists suggest?
- suggest that the higher the concordance rate between 2 ppl= more likely the trait is inherited
genetic explanation- gene-mapping studies?
comparing genetic material of OCD sufferers with non-sufferers to indicate a link with particular genes that makes ppl more vulnerable to OCD (candidate genes) –> likely to be a combination of genes, not just one (polygenic)
genetic explanation- diathesis stress model?
suggests certain genes make some ppl more likely to suffer from OCD, the environmental stress (experience) is necessary to trigger the condition
genetic explanation- what are the specific genes implicated in OCD?
COMT gene
SERT gene
genetic explanation- COMT gene
- helps to reduce the action of dopamine. Less COMT genes= dopamine isn’t controlled + there’s too much of it –> too much dopamine is associated with OCD
genetic explanation- SERT gene
- affects transport of serotonin –> creates lower levels of neurotransmitter serotonin –> serotonin has a role in balancing mood= can regulate obsessive thoughts –> low levels of it link with OCD
genetic explanation- strengths
- strong research support- Nestadt et al found 68% of MZ twins both had OCD vs 31% in DZ twins
- can use animal studies for research
genetic explanation- limitations
- biological reductionism- doesn’t account environmental factors which could lead to development of OCD –> Kiara Cromer et al found that over 1/2 OCD is more severe in ppl who’ve suffered with traumatic experiences
- animal studies may be useless as they’re not as complex as humans
- never found 100% concordance rate= other factors need to be looked into
- polygenic condition= hard to make correlations between genes linked to OCD, may differ from person to person
neural explanation- what does it assume
- assumes neurotransmitters play a role in development of OCD + structures of the brain
neural explanation- expand on it
serotonin regulates moods, low levels can lead to depression etc. It plays an active role in orbital frontal cortex + caudate nucleus –> low serotonin levels may lead to abnormal functioning in areas of brain involved in OCD
neural explanation- strengths
- antidepressants regulate serotonin levels = reduces OCD symptoms
- research often uses objective clinical methods e.g. fMRI scanning = increase reliability
neural explanation- limitations
- not all OCD sufferers respond positively to antidepressants= reduces external validity
- correlations don’t necessarily suggest cause + effect relationships (may be a third factor)
brain structure/neuroanatomy- OCD vs normal brain
- orbitofrontal cortex
OCD- detects error when isn’t one + sends ‘worry’ signals
N- integrates sensory info makes decisions, anticipates reward or punishment - cingulate gyrus
OCD- adds emotion like anxiety etc
N- adds emotional responses to thoughts - caudate nucleus
OCD- can’t filter anxious thoughts
N- process info + removes unwanted things - basal ganglia
OCD- causes repetitive behaviours
N- controls movements, thinking
brain structure/neuroanatomy- the worry circuit
- if caudate nucleus is damaged, it can’t suppress minor ‘worry signals’ + thalamus is alerted = sends signals to OFC + confirms worry= triggers compulsions + anxiety –> low levels of serotonin in brain areas could be linked to problem of signal regulation
brain structure/neuroanatomy- neurosurgery
- can treat parts of brain linked to OCD to improve symptoms (neurosurgery)
–> support for biological explanations as treating biological part= symptoms reduced
the OCD cycle
OBSESSIVE THOUGHTS –> ANXIETY
–> COMPULSIONS –> TEMPORARY RELIEF (then back to obsessive thoughts
the ocd cycle expansion
OBSESSIVE THOUGHTS (recurrent, intrusive unwanted distressing thoughts, images etc
ANXIETY (extreme fear, shame, guilt)
COMPULSIONS (reduced anxiety by performing behaviours/compulsions
TEMPORARY RELIEF (relief is only short term)
biological approach in treating OCD
drug therapy, antidepressants SSRI’s e.g. fluoxetine, CBT
drug therapy
- aims to increase or decrease levels of neurotransmitters in the brain –> drugs for OCD aim to increase serotonin in the brain
- drug treatment used if CBT doesn’t work
antidepressants (SSRI’s)
- most commonly used drug treatment for OCD
- they prevent the reuptake of serotonin in the synaptic cleft back into the presynaptic neuron
–> prevention of uptake= serotonin more accessible in the brain + available to improve transmissions of messages between neurons
other treatments of OCD (drug)
- BZs- anti-anxiety drug, reduces action of neurotransmitter GABA (which controls neuron hyperactivity= fear anxiety etc)= slows down brain= reduce obsessive thoughts etc
- SNRI’s- increase serotonin levels BUT have more side effects than SSRI’s
CBT
- first choice of treatment
- aims to change thought processes + behaviours
cognitive component: - aims to change beliefs that OCD person triggers. prevent cognitive distortion of catastrophising- help deal with obsessions
behavioural component:
- exposure and response prevention therapy focuses on compulsions
- exposes clients to situations that cause anxiety to help person resist performing behaviour –> uses exposure hierarchy (building up from situation that causes mild anxiety to full) –> repeated exposure till anxiety reduces + client resists + refrains from compulsive behaviour
biological approach in treating OCD- strengths
- drug therapy= less effective + widely available + non-disruptive (compared to CBT) –> good for economy as ppl return to work quicker + more for health service budget to spend on other things
- SSRI’s = shown to be effective Soomro et al found 17 studies showed better results from SSRI’s than placebos BUT shapinakis et al found that CBT= more effective than SSRIs
- little effort to take drugs
- can use CBT + drugs= more effective
biological approach in treating OCD- limitations
- serious side effects of drugs
–> SSRIs= blurred vision, nausea, insomnia BUT only temporary
–> BZ’s= long term memory impairment - biased evidence –> as research funded by research companies, publication= bias towards studies that have a positive outcome –> unethical? lower validity, are the drugs truly effective?
