ocd

• Obsessive-compulsive disorder (OCD)


  A mental health condition characterized by obsessive thoughts and compulsive behaviours
• OCD


  • Obsessive thoughts (recurring thoughts, images, etc)
  • Compulsions (repetitive behaviours such as handwashing)
• DSM-5 categories of OCD

  • OCD
  • Trichotillomania (compulsive hair-pulling)
  • Hoarding disorder
  • Excoriation disorder (compulsive skin-picking)
• Compulsions


  • Repetitive
  • Reduce anxiety
• Around 10% of people with OCD show compulsive behaviour alone - they have no obsessions, just a general sense of irrational anxiety
• For the vast majority of people with OCD, compulsive behaviours are performed in an attempt to manage the anxiety produced by obsessions
• Avoidance in OCD


  • People with OCD try to manage their OCD by avoiding situations that trigger anxiety
• Avoidance can lead people with OCD to avoid very ordinary situations, which can interfere with leading a regular life
• Emotional characteristics of OCD

  • Anxiety and distress
  • Accompanying depression
  • Guilt and disgust
• Cognitive characteristics of OCD

  • Obsessive thoughts
  • Cognitive coping strategies
  • Insight into excessive anxiety
• People with OCD are aware that their obsessions and compulsions are not rational
• People with OCD experience catastrophic thoughts about the worst case scenarios that might result if their anxieties were justified
• People with OCD tend to be hypervigilant, maintaining constant alertness and keeping attention focused on potential hazards
• Diathesis-stress model


  Certain genes leave some people more likely to develop a mental disorder, but environmental stress is necessary to trigger the condition
• Candidate genes


  Genes that create vulnerability for OCD
• OCD is polygenic, meaning it is caused by a combination of genetic variations rather than a single gene
• Heterogeneous


  The origins of OCD vary from one person to another
• Neural explanations for OCD


  • Role of serotonin
  • Decision-making systems
• At least some cases of OCD may be explained by a reduction in the functioning of the serotonin systems in the brain
• Some cases of OCD, particularly hoarding disorder, seem to be associated with impaired decision-making and abnormal functioning of the frontal lobes of the brain
• Genetic vulnerability


  Environmental risk factors can trigger or increase the risk of developing OCD
• Animal studies have shown that particular genes are associated with repetitive behaviours in other species, but it may not be possible to generalise from animal repetitive behaviour to human OCD
• Many people with OCD also experience clinical depression, which also involves disruption to serotonin activity, making it difficult to determine if serotonin is uniquely relevant to OCD symptoms