OCD

• What is OCD characterized by?

  Obsessions and compulsions
• How does OCD typically affect individuals?

  It causes a particular pattern of thoughts and behaviours
• What are the four main steps in the pattern of OCD?

  1. Obsession: Intrusive thought or urge
  2. Anxiety: Intense feelings of anxiety
  3. Compulsion: Repetitive behaviour to reduce anxiety
  4. Temporary relief: Anxiety returns, restarting the cycle
• What percentage of people will suffer from OCD at some point?

  Approximately 2%
• What category does OCD fall under in the DSM-5?

  Obsessive-Compulsive and Related Disorders
• What disorders are included in the Obsessive-Compulsive and Related Disorders category?

  • OCD
  • Hoarding disorder
  • Hair pulling disorder (Trichotillomania)
  • Excoriation (skin-picking) disorder
  • Body dysmorphic disorder
• What are the two main cognitive characteristics of OCD?

  1. Obsessions
  2. Hypervigilance
• What are obsessions in the context of OCD?

  Uncontrollable and intrusive thoughts or urges
• How do obsessions typically affect individuals with OCD?

  They create intense anxiety and are unpleasant
• What are some common obsessions in OCD?

  Fear of harm, contamination, order, and intrusive thoughts
• What does hypervigilance mean in the context of OCD?

  Constant alertness to potential hazards
• What are the two main emotional characteristics of OCD?

  1. Anxiety
  2. Accompanying depression
• How is depression related to OCD?

  OCD often accompanies feelings of low mood
• What are the two main behavioural characteristics of OCD?

  1. Compulsions
  2. Avoidance
• What are compulsions in OCD?

  Repetitive and ritualistic behaviours or acts
• Why do individuals with OCD perform compulsions?

  To manage anxiety produced by obsessions
• How do compulsions relate to the anxiety they aim to neutralize?

  They are often excessive or unrealistic
• What are some common compulsions in OCD?

  Excessive washing, cleaning, checking, ordering, counting
• How do compulsions affect a sufferer's daily life?

  They interfere with normal routines and relationships
• What is avoidance in the context of OCD?

  Avoiding situations that trigger obsessions
• How does avoidance affect individuals with OCD?

  It interferes with normal routines and activities
• What does the biological approach suggest about OCD?

  OCD has a physical cause
• How many biological explanations of OCD are there?

  Two biological explanations
• What are the two biological explanations of OCD?

  Genetic explanation and neural explanation
• What methods have been used to investigate the genetic basis of OCD?

  • Family studies
  • Twin studies
  • Studies of individual genes
• What have family studies shown about OCD?

  OCD is more common among biological relatives
• What did Lewis (1936) find about siblings of individuals with OCD?

  21% risk of being diagnosed with OCD
• What did Lewis (1936) find about parents of individuals with OCD?

  37% risk of being diagnosed with OCD
• What is the general risk of being diagnosed with OCD?

  2%
• What does the family study data suggest about OCD?

  OCD runs in families
• How do MZ twins compare to DZ twins in terms of OCD concordance?

  MZ twins are more concordant for OCD
• What was the concordance rate for OCD in MZ twins according to Nestadt et al. (2010)?

  68%
• What was the concordance rate for OCD in DZ twins according to Nestadt et al. (2010)?

  31%
• What does a higher concordance rate in MZ twins suggest about OCD?

  It suggests a genetic influence on OCD
• What are candidate genes in relation to OCD?

  • Are a no. of genes that have been related to OCD, called candidate genes
  • Taylor (2013) found evidence of up to 230 candidate genes for OCD  
  • Seems that OCD is polygenic - no. of different genes all confer a small increased risk
  • It also seems that OCD is aetiologically heterogeneous
  • This means that different combinations of genes can lead to the condition
• What does it mean that OCD is polygenic?

  It involves multiple genes contributing to risk
• What does aetiologically heterogeneous mean in the context of OCD?

  Different gene combinations can lead to OCD
• What is a weakness of genetic explanation for OCD


  Problems w family studies. E.g many researchers accept fact that OCD runs in families may be more to do w common rearing patterns / other environmental factors that have nothing to do w heredity. Suggests family studies lack internal validity.
• What is a weakness of genetic explanation for OCD

  Weakness = clear that OCD not a purely genetic disorder. Bc concordance rates 4 MZ twins are not 100%. Diathesis-stress model explains this -> suggests individuals inherit a susceptibility to OCD, but the disorder itself will only develop if individual exposed to stressful life conditions. Cromer et al. (2007) found over half of OCD patients in their sample had traumatic event in their past, and OCD most severe in those w more than one trauma. Suggests -> although genetics may contribute to development OCD, cannot offer complete explanation. 
• What does the neural explanation of OCD suggest as causes?

  Abnormal neurotransmitter levels and brain structures