Explanations of OCD Flashcards
(26 cards)
What is OCD
A anxiety disorder where anxiety arises from both obsessions (persistent thoughts) and compulsions (behaviours that are repeated over and over again).
Compulsions are a response to obsessions and the person believes the compulsions will reduce anxiety
What are the behavioural characteristics of OCD
Compulsions: Behaviours are performed to reduce the anxiety created by obsessions. They are repetitive and unconcealed
Avoidance: Keeping away from situations that trigger the OCD/anxiety.
What are the emotional characteristics of OCD
Anxiety, worry and distress: Obsessions and compulsions are a source of considerable anxiety and distress. Sufferers are aware that their behaviour is excessive and this causes feelings of embarrassment and shame.
Guilt and disgust: OCD often involves other negative emotions such as irrational guilt or disgust, which may be directed against something external like dirt or at the individual.
Accompanying depression: OCD is often accompanied by depression. Compuslisive behaviour only brings a temporary relief from anxiety
What are the cognitive characteristics of OCD
Obsessive thoughts: Obsessions are recurrent, intrusive thoughts
Insight into excessive anxiety: The person recognises that the obsessional thoughts or impulses are a product of their own mind but they feel that they cannot control them.
Hyper vigilance: Sufferers will maintain constant alertness and keep attention focused on potential hazards.
Outline the genetic explanation of OCD
Individuals inherit specific genes from their parents that are related to the onset of OCD.
Genes include: COMT gene, SERT gene and polygenetic
Describe the COMT gene
COMT regulates the production of the neurotransmitter dopamine that has been implicated in OCD.
One form of the COMT gene has been found to be more common in OCD patients than people without the disorder.
This variation produces lower activity of the COMT gene and therefore higher levels of dopamine
Describe the SERT gene
Affects the transport of serotonin, creating lower levels of this neurotransmitter.
Ozaki et al found a mutation of this gene in two unrelated families where 6 out of 7 family members had OCD.
SERT gene is also implicated in a number of other disorders such as depression and PTSD
Describe polygenetic
Polygenetic refers to a characteristic that is that is influenced by 2 or more genes.
It is possible that a number of caudate genes may have been implicated as a possible cause for OCD.
For example, Taylor (2013) identified up to 230 caudate genes associated with OCD, suggesting that OCD is polygenetic.
What is aetiological heterogeneity
OCD may have A.H meaning that different combinations of genes that may cause the OCDin different people
- In other words different combinations of genes can result in OCD, as opposed to an individual gene or the same combination of genes in all people.
What is a strength of the genetic explanation of OCD
Supported by evidence
What are limitations of the genetic explanation of OCD
Doesnt explain all OCD
Reductionist
Evaluate research support as a strength of the genetic explanation of OCD
P: Supported by evidence.
E: Nestadt et al found that people with a first degree relative with OCD had 5x greater risk of having the illness compared to the general population.
Billett et al (1998) found that concordance rates of OCD were double for monozygotic twins than dizygotic twins.
E: Strength of the genetic explanation of OCD because these findings suggests that OCD is inherited. The occurrence of OCD seems to run in families rather than the specific symptoms which shows that there is at least an environmental contribution to OCD in terms of the symptoms.
Therefore, the evidence suggests the biological explanation of OCD is valid.
Evaluate that it doesn’t explain all types of OCD as a limitation of the genetic explanation of OCD
P: There is only partial evidence for a genetic link to OCD and therefore does not explain all cases of OCD.
E: Grootheest et al reviewed 70 years of twin studies on OCD, over 10,000 twins. They concluded that OCD is heritable with the genetic influence ranging from 45 to 65%. However, evidence for a genetic link for OCD that developed in adulthood was much smaller.
E: This is a limitation because there is weaker evidence for a genetic cause of OCD when it occurs in adults as opposed to children.
Suggests the genetic approach provides an incomplete explanation of OCD and therefore has limited validity.
Evaluate reductionism as a limitation of the genetic explanation of OCD
P: Reductionist because it only uses genes as an explanation and ignores psychological causes such as environmental factors.
E: Environmental factors also can cause OCD. Cromer et al found that over half of people with OCD who they studied had a traumatic event in their past, the more trauma the more severe the symptoms.
The diathesis-stress model suggests that OCD is not caused by one factor but instead suggests that the individual has a genetic pre- disposition to OCD which is triggered by environmental stimuli. This is supported by the fact that concordance rates in twin studies are never 100% which means that environmental factors must play a role too.
E: Limitation of the biological explanation of OCD as it suggests that the approach is reductionist and a too simplistic ‘nature’ theory.
Therefore the genetic approach provides an incomplete explanation of OCD and an interactionist explanation combining both genetic and environmental factors would provide a better explanation.
What are some neural explanations of OCD
- Abnormal levels of neurotransmitters
- Abnormal brain curcuits
- Worry circuit
Describe abnormal levels if neurotransmitters (dopamine) as an explanation for OCD
Dopamine levels are thought to be abnormally high in people with OCD.
Szechtman carried out studies on animals and found high doses of drugs that enhance levels of dopamine induced stereotyped movements resembling the compulsive behaviours found in OCD patients.
Describe abnormal levels if neurotransmitters (serotonin) as an explanation for OCD
Lower levels of serotonin are associated with OCD.
Antidepressant drugs that increase serotonin activity have been shown to reduce OCD symptoms whereas antidepressants that have less effect on serotonin do not reduce OCD symptoms
Describe abnormal brain circuits as a neural explanation of OCD
Some cases of OCD are associated with impaired decision making which may be as a result of abnormal functioning of the lateral of the frontal lobes of the brain.
Also evidence that the parahippocampal gyrus which processes unpleasant emotions, functions abnormally in OCD.
Describe the worry circuit as a neural explanation of OCD
‘worry circuit’, in the brain.
The two main areas of the brain associated with OCD are the Orbit Frontal Cortex (OFC), the caudate nucleus and thalamus.
What is the function of the Orbit frontal cortex
OFC is responsible for sending the worry signals, which are picked up by the thalamus and directed around the body.
What is the function of the caudate nucleus
The caudate nucleus is responsible for suppressing some of these worry signals.
If the caudate nucleus is not working properly, the worry signals do not get surpressed, and a person worries too much this can cause OCD
What is a strength of the neural explanation of OCD
practical applications
What are limitations of the neural explanation of OCD
Treats symptoms not causes
Oversimplistic
Evaluate practical applications as a strength of the neural explanation of OCD
P: Produced a successful treatment for OCD.
E: For example, anti-depressants such as SSRIs and anti-anxiety drugs such as Benzodiazepines (BZs), and an antibiotic called D-Cycloserine have been used to successfully treat OCD.
E: This is a strength because, as the treatment is based on the assumptions of the approach, the approach must be at least partially valid. This is therefore strong evidence for the neural explanation of OCD which helps to improve peoples’ lives
