Biological approach: explaining OCD Flashcards
What are the 2 biological approaches of explaining OCD?
- Genetic explanation of OCD
- Neural explanation of OCD
What does the genetic explanation of OCD state?
- Genetic evidence has found first degree relatives of people with OCD have a greater vulnerability of developing the disorder.
- Nestadt et al found that 1st degree relatives of OCD sufferers had a 12% chance of developing OCD compared to a 3% risk in the general population.
- Research also found that a specific gene type could be responsible for OCD called ‘candidate genes’. These genes are involved in regulating the production of the neurotransmitter serotonin that’s implicated in OCD.
- If the SERT gene is impaired, it leads to diminished levels of neurotransmitter serotonin.
If the point is:
One strength of the genetic explanation for OCD is that there’s evidence for the role of genes in the development of the disorder.
What is the evidence, explanation and link?
Evidence- For example, Nestadt conducted a review of twin studies and found a concordance rate of 67% for monozygotic twins, but only a 31% concordance rate for dizygotic twins.
Explanation- Hence, the closer the genetic relationship to a sufferer, the greater the risk of developing OCD.
Link- This suggests that genetics are certainly involved in the transmission of OCD.
If the point is:
However, a weakness of the genetic explanation for OCD is that research also demonstrates that genes cannot be the only factor in the development of OCD.
What is the evidence, explanation and link?
Evidence- This is because, if genes were the only explanation, then monozygotic twins would show 100% concordance in OCD.
Explanation- As this isn’t the case, there must also be environmental influences, like imitation of role models.
Link- Therefore, the genetic explanation of OCD could be seen as theoretically flawed.
If the point is:
Another strength of the genetic explanation for OCD is that it promotes psychology as a scientific discipline.
What is the evidence and link?
Evidence- This is because genetics can be studied objectively and reliably by using DNA analysis and studying family history.
Link- Therefore, the explanation gains support from the field of science and could be seen as a more reliable explanation of the development of OCD.
If the point is:
Alternatively, a weakness of the genetic explanation for OCD is that it can be considered biologically reductionist, as it ignores factors other than genes that may affect the development of OCD.
What is the evidence and link?
Evidence- Such as, the role of early trauma in childhood, which has been repeatedly linked to OCD.
Link- This implies that the genetic explanation may be limited in explaining OCD, as there may be other reasons for the development of OCD.
What does the neural explanation of OCD state?
- The caudate nucleus normally suppress signals from the orbital frontal cortex
- In turn, the OFC sends signals to the thalamus about things that are worrying
- When the caudate nucleus is damaged, it fails to suppress these worry signals and the thalamus is alerted
- The thalamus then sends signals back to the OFC, acting as a ‘worry circuit’
If the point is:
One strength of the neural explanation for OCD is that there’s research to support the role of brain dysfunction in the development of the disorder.
What is the evidence, explanation and link?
Evidence- For example, Ursu and Carter monitored brain activity in 15 OCD patients using fMRI scans and found hyperactivity in the orbital frontal cortex.
Explanation- This research suggests the orbital frontal cortex may play a part in the development of OCD.
Link- This supports the idea that abnormal brain structures may be a possible causal factor in the development of OCD.
If the point is:
However, a weakness of the neural explanation of OCD is that the link between OCD and brain abnormality is merely correlational and we cannot establish cause and effect.
What is the evidence and link?
Evidence- For example, much of the research into biological explanations for OCD is correlational, meaning the 2 variables occur at the same time. However, we cannot conclude that 1 variable causes the other.
Link- Hence, it could be argued that these biological abnormalities are a result rather than a cause of OCD.
If the point is:
A strength of the neural explanation of OCD is that it’s been practically applied to help our society and the 2-3% of the population who suffer from OCD.
What is the evidence and link?
Evidence- For example, SSRI’s are a drug often prescribed to people with OCD, which helps to increase the activity of serotonin in the brain.
Link- This illustrates how the neural explanation for OCD can actually reduce distress by many of those affected with OCD.
If the point is:
Another strength of the neural explanation of OCD is that it’s praised for being highly scientific.
What is the evidence, explanation and link?
Evidence- This is because genetics can be studied objectively and reliably by using DNA analysis and studying family history (concordance rates).
Explanation- This would suggest that the genetic explanation of OCD promotes psychology as a scientific discipline.
Link- This implies that the neural explanation can be viewed as a credible explanation for the development of OCD, as research into it has scientific rigor.
