P - the biological approach to explaining OCD (AO3) Flashcards
What’s a strength of the genetic explanation for OCD? - Supporting empirical evidence from twin studies
===> Nestadt et al (2010) found 68% of identical twins shared OCD compared to 31% of non-identicals. Monozygotic twins (sharing 100% of DNA) more likely to develop OCD than dizygotic (sharing 50% of DNA) - those who are more genetically similar are more likely to develop OCD. Increases validity but as concordance rates aren’t 100%, other factors must be involved
What’s a limitation of the genetic explanation for OCD? - Doesn’t consider how genes might interact with the environmental factors
===> Cromer et al (2007) found that half of OCD sufferers in sample had experienced traumatic past event and their OCD was more severe in those that had more than 1 trauma. Suggests genetics alone don’t lead to OCD and better explanation would be diathesis-stress model. Genetic explanation might be too biologically reductionist
What’s a limitation of the genetic explanation for OCD? - Too many candidate genes for practical value
===> Taylor (2013) identified potential 230 genes involved in disorder and genetic variation only increases risk by a fraction - difficult to establish cause and effect. Limits usefulness in real world as too complex to have any practical application until further research highlights a more concrete explanation
What’s a strength of the neural explanation for OCD? - Supportive empirical evidence that OFC has a role in OCD
===>Menzies et al (2007) used MRI to assess brain activity in OCD sufferers, their immediate fam and a control group. Found all except control had reduced grey matter in key regions of brain, including OFC. Supports explanation differences in brain structure is possibly inherited but also supports diathesis-stress model as family members didn’t have OCD. Useful real-world application as brain-scanning could help identify OCD
What’s a strength of the neural explanation for OCD? - Empirical evidence that neurotransmitters play a role
===> Antidepressants work on neural system and SSRIs increase serotonin levels and both are effective at reducing OCD symptoms. Suggests neural explanation is valid but evidence is correlational - drugs may not have solely improved symptoms (placebo mechanism could have played a role)
