The Biological Approach to Explaining OCD

Question 1

What are candidate genes in relation to OCD?

Answer 1

Specific genes such as 5HT1-D beta are associated with OCD and influence serotonin transmission.

Question 2

How are serotonin and dopamine involved in OCD?

Answer 2

Low serotonin is linked to OCD, as it disrupts mood regulation; dopamine may also play a role.

Question 3

What does it mean that OCD is polygenic?

Answer 3

Up to 230 genes may contribute to OCD, each increasing vulnerability slightly.

Question 4

What is meant by aetiological heterogeneity in OCD?

Answer 4

Different genes may be involved in OCD for different individuals, meaning multiple genetic variations can lead to the disorder.

Question 5

How is low serotonin linked to OCD?

Answer 5

It disrupts the transmission of mood-related messages, which may contribute to OCD symptoms.

Question 6

What brain areas are implicated in OCD?

Answer 6

The frontal lobes and parahippocampal gyrus are linked to impaired decision-making and emotional regulation.

Question 7

Strength: What evidence supports a genetic influence in OCD?

Answer 7

Evidence: Nestadt et al. (2010) – 68% concordance in MZ twins vs. 31% in DZ twins.

Indicates strong genetic contribution.

Question 8

Limitation: What role do environmental risk factors play in OCD?

Answer 8

Evidence: Cromer et al. (2007) – over 50% of OCD patients had past trauma.

Suggests that environmental factors are also important.

Question 9

Strength: How do SSRIs provide support for the biological model?

Answer 9

Evidence: SSRIs reduce OCD symptoms by increasing serotonin levels.

Shows a link between serotonin imbalance and OCD.

Question 10

Limitation: Why is there no unique neural system for OCD?

Answer 10

Evidence: Neural abnormalities in OCD are also found in depression.

Suggests that these brain issues aren’t specific to OCD.