Psychopathology- The Biological Approach To Explaining OCD Flashcards
Biological approach -
A perspective that emphasises the importance of physical processes in the body such as genetic inheritance and neural function.
Genetic explanations -
Genes make up chromosomes and consist of DNA which codes the physical features of an organism (such as eye colour, height) and psychological features (such as mental disorder, intelligence). Genes are transmitted from parents to offspring, i.e. inherited.
Neural explanations -
The view that physical and psychological characteristics are determined by the behaviour of the nervous system, in particular the brain as well as individual neurons.
What does the genetic explanation of OCD suggest?
The genetic explanation suggests that OCD may have a biological basis, with genes contributing to individual vulnerability to the disorder.
What evidence supports the idea that OCD runs in families?
Lewis (1936) found that 37% of OCD patients had parents with OCD, and 21% had siblings with the condition, suggesting a genetic link.
What does genetic vulnerability mean in the context of OCD?
Genetic vulnerability refers to the increased likelihood of developing OCD due to inherited genetic factors, but it does not guarantee the development of the disorder.
What is the diathesis-stress model in relation to OCD?
What are candidate genes in OCD?
Candidate genes are genes identified as contributing to OCD vulnerability. These genes often affect the regulation of neurotransmitters like serotonin.
Which gene is associated with serotonin transport in OCD?
The gene 5HT1-D beta is involved in the efficiency of serotonin transport across synapses, which may play a role in OCD development.
What does it mean that OCD is polygenic?
OCD is polygenic, meaning it is caused by multiple genes rather than just one single gene.
How many genes might be involved in OCD according to Taylor (2013)?
Taylor (2013) found that up to 230 different genes could be involved in OCD, including genes related to dopamine and serotonin.
What is aetiological heterogeneity in relation to OCD?
Aetiological heterogeneity means that OCD can have different causes in different individuals, with different sets of genes contributing to the disorder in each case.
How might genetic variations affect different types of OCD?
Different genetic variations may lead to different types of OCD, such as hoarding disorder or religious obsession.
How do genes affect neurotransmitter systems in OCD?
Genes associated with OCD likely influence neurotransmitter levels, such as serotonin, and can impact brain regions involved in mood and emotional regulation.
What role does serotonin play in OCD?
Serotonin is a neurotransmitter that helps regulate mood. Low levels of serotonin may impair the transmission of mood-relevant information in the brain, contributing to OCD symptoms.
How is serotonin linked to the development of OCD?
A reduction in serotonin functioning can contribute to OCD, as the neurotransmitter plays a critical role in regulating mood and behavior.
How does impaired decision-making relate to OCD?
Some cases of OCD, especially hoarding disorder, involve impaired decision-making, which may be associated with abnormal functioning of the frontal lobes.
What are the frontal lobes responsible for, and how do they relate to OCD?
The frontal lobes are involved in logical thinking and decision-making. Abnormalities in these areas may contribute to the decision-making difficulties seen in some forms of OCD.
What is the role of the left parahippocampal gyrus in OCD?
The left parahippocampal gyrus is associated with processing unpleasant emotions. It has been shown to function abnormally in people with OCD.
What is the supporting evidence for the genetic explanation of OCD?
Twin studies provide strong evidence for a genetic basis of OCD. Nestadt et al. (2010) found that 68% of identical twins shared OCD, compared to 31% of non-identical twins, suggesting a genetic influence.
Why is it difficult to identify all the genes responsible for OCD?
OCD is polygenic, meaning multiple genes are involved. Each genetic variation increases the risk of OCD only slightly, making it difficult to pinpoint the exact genes involved.
Q: What limitation does the genetic explanation of OCD have in predicting the disorder?
A: Because several genes are involved, the genetic explanation provides limited predictive value, making it difficult to predict who will develop OCD.
Q: How do environmental factors contribute to the development of OCD?
A: Environmental factors, such as traumatic events, can trigger or increase the risk of developing OCD, particularly in those who are genetically predisposed.
Q: What did Cromer et al. (2007) find about environmental factors in OCD?
A: Cromer et al. (2007) found that over half of OCD patients had experienced a traumatic event, and those with multiple traumas had more severe OCD symptoms.
Q: Why can OCD not be entirely genetic in origin?
A: Environmental factors also play a significant role, as shown by research indicating that OCD symptoms are often linked to past traumatic experiences.
Q: What role do neural mechanisms play in OCD?
A: Neural mechanisms, particularly the serotonin system, are involved in OCD. Medications that affect serotonin levels can help reduce OCD symptoms, suggesting a biological basis.
Q: What evidence supports the idea that serotonin is involved in OCD?
A: Antidepressants that increase serotonin levels have been shown to reduce OCD symptoms, suggesting that serotonin dysfunction is linked to the disorder.
Q: Are other conditions with biological origins linked to OCD?
A: Yes, conditions like Parkinson’s disease, which have a biological basis, also show symptoms similar to OCD, supporting the idea that biological processes may underlie OCD.
Q: What do studies of decision-making systems reveal about OCD?
A: Research has shown that the same decision-making systems in the brain that function abnormally in OCD are also linked to impaired decision-making seen in OCD patients.
Q: Why is it difficult to understand the neural mechanisms involved in OCD?
A: No single brain system has been found to always play a role in OCD, making it difficult to fully understand the neural mechanisms involved in the disorder.
Q: Should we assume that abnormal neural functioning causes OCD?
A: Abnormal neural functioning may be a result of OCD rather than its cause. It is not clear whether these abnormalities directly cause OCD.
Q: How does co-morbidity with depression affect the serotonin-OCD link?
A: Many individuals with OCD also have depression, which can disrupt serotonin functioning. This raises the possibility that serotonin abnormalities could be caused by depression, rather than being the cause of OCD.
Q: What is the problem with assuming serotonin is directly linked to OCD?
A: Since depression often co-occurs with OCD, it is possible that serotonin dysfunction is linked to depression and not directly to OCD. This complicates the understanding of serotonin’s role in OCD.
Q: What are the limitations of twin studies in genetic research on OCD?
A: Twin studies assume that identical twins are only more similar due to their genetic makeup, but they may also share similar environments, which could confound the results. Non-identical twins may have different environmental experiences, further complicating the findings.
How do the shared environments of identical twins affect the validity of twin studies in OCD research?
The shared environments of identical twins may mean that their similarity in OCD could be due to environmental factors as well as genetic ones, reducing the validity of twin studies in determining the genetic influence on OCD.
The diathesis-stress model suggests that while certain genes may increase susceptibility to OCD, environmental stressors or experiences are necessary to trigger the condition.
