Why does it develop biologically

• What is the genetic explanation of OCD?

  OCD is partly inherited and runs in families.
• What are candidate genes in relation to OCD?

  Genes involved in regulating serotonin and dopamine.
• Which gene affects serotonin transport?

  SERT gene
• What does the COMT gene regulate?

  Dopamine levels
• How many genes are involved in OCD according to Taylor (2013)?

  Up to 230 genes
• What does aetiologically heterogeneous mean in the context of OCD?

  Different genes may cause OCD in different people.
• What neurotransmitter is linked to poor mood regulation in OCD?

  Serotonin
• What is the link between high dopamine and OCD?

  It may be linked to compulsive behaviours.
• Which brain structure is overactive in OCD and linked to repetitive behaviours?

  Basal ganglia
• What role does the orbitofrontal cortex (OFC) play in OCD?

  Involved in decision-making and detecting threats.
• How does the thalamus contribute to OCD?

  It relays worry signals back to the OFC.
• What evidence supports the genetic explanation of OCD?

  • Twin studies: 68% concordance in MZ twins
  • 31% concordance in DZ twins
  • Brain scans show increased OFC activity in OCD patients
  • SSRIs reduce symptoms, supporting serotonin link
• What are the strengths of the biological explanation of OCD?

  Scientific, objective, and leads to effective treatments.
• What does "correlation ≠ causation" imply in the context of OCD?

  Low serotonin may be a symptom, not a cause.
• Why is the biological explanation considered reductionist?

  It ignores cognitive and behavioural factors.
• What are the limitations of the biological explanation of OCD?

  Not 100% genetic; environmental factors play a role.
• What is the worry circuit in OCD?

  • Involves OFC, thalamus, and basal ganglia
  • OFC detects threats and signals worry
  • Thalamus relays signals back to OFC
  • Creates a feedback loop of worry
• What is the diathesis stress model?

  That certain genes leave people more susceptible to ocd but there needs to be a trigger to develop it