1.4 - Psychopathology (set B - OCD) Flashcards
(37 cards)
What is Obsessive-compulsive disorder (OCD)?
Anxiety disorder characterised by irrational, persistent and intrusive thoughts (obsessions) which are coupled with intense uncontrollable urges to complete tasks (compulsions)
Give an example of an obsessive thought and compulsive behaviour?
Obsessive thought could be that germs lurk everywhere
Compulsive behaviour could be repetitive hand washing every 10 mins to get rid of the percieved germs
Outline the behavioural characteristics of OCD?
- involves repetitive compulsions which the suffer is compelled to repeat over a continuing long period of time
- compulsions reduce anxiety produced by obsessions
- avoidance - suffers may try to reduce anxiety levels by staying way from situations which link to their obsessions
Outline 2 ways someone suffering from OCD may try to reduce the anxiety through behaviour - give an example for each?
- performing repetitive compulsions over a continuing period of time in order to reduce anxiety produced by obsessions (eg constantly watching hands)
- avoiding the situation which causes fear or are related to their obsession (eg not emptying bins due to presence of germs)
Outline the emotional characteristics of OCD?
- can be frightening and overwhelming - due to powerful anxiety and constant obsessions/compulsions
- often accompanied with Depression - around 25 to 50% of people with OCD have depression
- Negative emotions (eg disgust and guilt) plagues sufferers - can be directed at self or externally at world
Outline the emotional characteristics of OCD?
- nearly all experience recurrent, unpleasant and obsessive thoughts
- sufferers can respond to obsessive thoughts by using cognitive coping strategies - eg praying
- are aware that obsessions and compulsions are irrational - still feel real and cause extreme anxiety
Outline 2 biological approaches to explaining and treating OCD - very briefly explain basis of each?
- Genetic - focuses on genes, inherited from parents - idea OCD is inherited
- Neural - focuses on neurotransmitters which are responsible
What does the genetic approach outline as the cause of OCD?
- OCD is understood as being largely biological in nature
- specific genes (candidate genes) may contribute to OCD (COMPT and SERT) and create vulnerability for OCD
What does the genetic approach suggest about COMPT genes?
- responsible for regulating neurotransmitter dopamine by clearing dopamine away from synapses
- low activity of the COMPT gene has been shown to to be associated with OCD and higher dopamine levels
What does the genetic approach suggest about SERT genes?
- affects transport of serotonin (involved with how we feel)
- levels of the genes can cause lower levels of serotonin which has been shown to be associated with OCD and depression
Outline the diathesis-stress component of the genetic explanation of OCD?
- unlikely there is link between one gene and a complex disorder like OCD
- genes like the SERT gene are implicated in a number of other disorders like depression and PTSD
- suggest each individual gene only creates a vulnerability (diathesis) for OCD - other factors (‘stressors’) affect what condition develops
What does the diathesis-stress hi-light as the cause of disorders like OCD?
Suggests that each individual gene only creates a vulnerability (diathesis) for OCD - it is the factors (“stressors’) that affect what condition develops
- environmental stress can trigger psychological disorders
Outline what candidate genes are in regard to the genetic explanation for OCD?
genes which create vulnerability for OCD
- for example the COMPT and SERT genes are candidate genes which interact with neurotransmitters
What does the genetic explanation for OCD mean by describing OCD as polygenic?
Acknowledges that multiple genes are associated with OCD rather then just one single gene
- Taylor (2013) found evidence of the involvement of 230 different genes
- combination of genes can cause different types of OCD
Outline the family study (Nestadt et al) as support for the genetic explanation of OCD?
Identified 80 patients with OCD and 343 of their first-degree relatives - compared them with 73 control patients without mental illness and 300 of their relatives
- found people with a first degree relative with OCD have 5 times greater risk of having it aswell
What did twin study (Nestadt et al) find about identical and non-identical twins and the presence of OCD?
Meta-analysis of 14 twin studies of OCD - found that on average identical (monozygotic) twins were twice as likely to develop OCD if their co-twin had the disorder than was the case for non-identical (dizygotic) twins
- clear genetic basis for OCD - however concordance rates are never 100% so environmental factors invovled
Outline 2 strengths for the genetic explanation for OCD?
- Good supporting evidence from a wide range of sources which suggest genetic vulnerability (found having a first degree relative with OCD increases risk of having it as well by 5 times)
- Family and twin studies (Nestadt et al) - shows that concordance rate is not 100% so environment must also play a role - supports diathesis stress
Outline 2 weaknesses for the genetic explanation for OCD?
- have not yet managed to successfully pin down all the genes involved - can’t provide a useful, predictive value for the disorder only implication of certain genes
- environmental factors seem to also trigger OCD - Cromer et al study found that more than 50% of suffers in their sample had a traumatic event in their past
What does the neural explanation outline as the cause of OCD?
- abnormal levels of neurotransmitters, in particular serotonin and dopamine, are implicated in OCD
- suggests that particular regions of the brain (particular the basal ganglia and orbitofrontal cortex) are implicated in OCD
Outline the role of serotonin and dopamine with reference to the neural explanation of OCD?
- dopamine levels are abnormally high in people with OCD (based on animal studies) - low serotonin associated with OCD
- based on antidepressant drugs that increase serotonin activity and have been shown to reduce OCD symptoms
Explain the descion making system component of the neural explanation?
- different forms of OCD associated with impaired decision making - eg hoarding
- potential association with frontal lobe of brain (responsible for executive function, personality and impulse control) being abnormally functioning
- PET scans shown heightened activity in brain region when sufferers are experiencing symptoms
Outline how abnormal brain circuits may be an explanation of OCD - neural explanation?
- orbital frontal cortex (OFC) part of the brain sends signals to thalamus about things that are worrying, the caudate nucleus is in between and responsible for regulating signals from the OCF this means that the hypothalamus doesn’t get hyperactive
- damaged or abnormal caudate nucleus fails to suppress minor ‘worry’ signals and the thalamus is alerted, which in turn sends a signal back to the OFC - causes anxiety and impulsive behaviours to occur
Outline the worry circuit component of the neural explanation?
- orbital frontal cortex sends signals to thalamus about worrying things - caudate nucleus regulates the signals and stops the hypothalamus becoming hyperactive
- abnormal caudate nucleus fails to suppress minor ‘worry’ signals - results in anxiety and impulsive behvaiour
- cyclical nature of signals known as worry circuit
Outline 2 strengths of the neural explanation to OCD?
- Some supporting evidence for the role of neural mechanisms in OCD - linked biological conditions eg parkisons disease share symptoms suggesting the same biological processes may be implicated
- allows for effective biological treatments which can target solely the serotonin system
