OCD

• What does OCD stand for ?

  Obsessive compulsive disorder
• what is OCD ?

  an anxiety disorder characterised by persistent, recurrent, unpleasant thought and repetitive, ritualistic behaviours
• what are obsessions ?

  thoughts which cause extreme feelings of anxiety

  forbidden or inappropriate ideas and visual images that are not based in reality
• what are compulsions?


  actions which are meant to reduce the stress and anxiety caused by the obsessions

  uncontrollable urges to perform the same repetitive tasks

  a temporary solutions
• what does OCD make an individual unable to do?


  the ability to conduct day to day activities
• what percentage of the population does ODC effect ?

  2%
• are there gender differences in OCD?

  none apart from what they are obsessive over
• what is the most common obsession in females with OCD?

  cleaning
• what are the most common obsessions in males who have OCD?

  religious

  sexual
• which gender has earlier onset of OCD?

  males
• what are behavioural symptoms of obsessions?

  hinder everyday functioning

  social impairment
• what are emotional symptoms of obsessions

  extreme anxiety
• what are cognitive symptoms of obsessions?

  recurrent and persistent thoughts

  recognised as self-generated

  realisation of inappropriateness

  attentional bias
• What are some common obsessions?

  Contamination/germs

  Fear of loosing control

  Perfection

  Religion
• what are behavioural symptoms of compulsions?

  repetitive

  hinders everyday functioning

  social impairment
• what are emotional symptoms of compulsions?

  distress
• what are cognitive symptoms of compulsions?

  uncontrollable urges

  Realisation of inappropriateness
• What is the genetic explanation of OCD?

  OCD is inherited through genetic transmission

  This means OCD is passed from parents to children at conception
• what are the two ways the genetic explanation of OCD can be studied?

  twin studies

  genetic mapping
• what is genetic mapping ?

  DNA profiling and comparing the DNA of OCD sufferers with non-OCD sufferers

  suggests that specific genes are involved in making someone vulnerable to a disorder

  unlikely to be a single gene that causes OCD but rather a combination
• What are twin studies ?

  Used to determine whether a disorder is inherited

  This is because twins are thought to share a more similar environment than ordinary brothers and sisters , this acts as a control and therefore no effect from the environment
• what are monozygotic twins ?

  Identical twins

  Share the same genes

  One egg one sperm , egg splits into two
• what are dizygotic twins?

  non-identical

  50% of the same genes

  two eggs two sperm
• what is a concordance rate ?

  the likelihood that a co-twin will have a disorder if we know that the other twin has it
• what are criticisms of the biological explanation of OCD?

  MZ twins do not have 100% concordance rate

  MZ twins look like each other and may be treated more similarly than DZ twins

  genes never directly cause a behaviour

  genetics alone cannot fully explain the development of the disorder

  some obsessions and compulsions appear to be more genetic than others

  family members often display dissimilar OCD symptoms

  OCD can be copied through the social learning theory
• What was the aim of Grootheest et al. (2005) study on OCD?

  To determine the likelihood that OCD is inherited
• What was the second aim of the Grootheest et al. (2005) study?

  To see if OCD inheritance differs in children and adults
• What types of studies were reviewed in the Grootheest et al. (2005) meta-analysis?

  • Old literature from 1929-1965
  • Studies meeting modern criteria
• How many twin pairs were studied in total by Grootheest et al. (2005)?

  10,034 twin pairs
• How many twin pairs were included from old literature in the study?

  37 twin pairs
• How many twin pairs were included from modern studies in the Grootheest et al. (2005) study?

  9,997 twin pairs
• What percentage range of heritability for OCD symptoms was found in children?

  45-65%
• What percentage range of heritability for OCD symptoms was found in adults?

  27-47%
• What does the conclusion of the Grootheest et al. (2005) study indicate about OCD?

  There is a genetic bias to OCD symptoms
• What were the evaluation points regarding the twin studies of OCD?

  • Majority were not large enough
  • Poor methodological conditions
  • Need for further controlled studies
• What are the suggested areas for further research in OCD heritability?

  • Assess different sub-types of OCD
  • Include more gene-mapping studies
  • Compare MZ and DZ twin data
• What did Lenane et al (1990) study regarding OCD?

  Prevalence of OCD among related family members
• What did Lenane et al (1990) find about OCD?

  Evidence for heritable contributions to OCD onset
• What method did Samules et al (2007) use in their research on OCD?

  Gene mapping
• What was the focus of Samules et al (2007) study on OCD?

  Compulsive hoarding behavior in OCD sufferers