AO1

• What is a strong biological component in mental health disorders?

  OCD
• What does the genetic explanation suggest about OCD?

  Genes contribute to individual vulnerability to OCD
• What percentage of Lewis's OCD patients had parents with OCD?

  37%
• What does the observation of OCD in families suggest?

  OCD runs in families due to genetic vulnerability
• What is the diathesis-stress model in relation to OCD?

  It combines genetic vulnerability and environmental stress
• What does 'diathesis' refer to in the diathesis-stress model?

  The biological part of the model
• What does 'stress' refer to in the diathesis-stress model?

  The environmental part that triggers OCD
• What are candidate genes in relation to OCD?

  Genes that create vulnerability for OCD
• What role do candidate genes play in OCD?

  They regulate the serotonin system's development
• Which gene is implicated in serotonin transport efficiency?

  5HT1-D beta
• What does it mean that OCD is polygenic?

  Multiple genes are involved in causing OCD
• How many different genes may be involved in OCD according to Taylor?

  Up to 230 different genes
• What neurotransmitters are associated with OCD?

  Dopamine and serotonin
• What does aetiologically heterogeneous mean in relation to OCD?

  Different causes for OCD in different individuals
• What types of OCD may arise from genetic variations?

  Hoarding disorder and religious obsession
• What is the role of dopamine in the brain?

  Feeling of pleasure and motivation
• How does serotonin contribute to well-being?

  It helps regulate mood and happiness
• What factors can affect serotonin levels?

  Exercise and light exposure
• What are the frontal lobes responsible for?

  Logical thinking and making decisions
• What area is associated with processing unpleasant emotions in OCD?

  Left parahippocampal gyrus
• What neurotransmitter is implicated in OCD?

  Serotonin
• What is the role of neurotransmitters?

  Relaying information between neurons
• What happens if a person has low levels of serotonin?

  Mood and mental processes are affected
• What may explain some cases of OCD?

  A reduction in serotonin system functioning
• What travels along the presynaptic neuron?

  Action potential
• What triggers the release of neurotransmitters?

  Action potential reaching the synapse
• What happens to serotonin after it binds to receptor cells?

  It is released and taken up again
• How does a lack of serotonin affect individuals with OCD?

  Messages are not passed effectively between neurons
• What is associated with impaired decision making in OCD?

  Abnormal functioning of the frontal lobes