OCD

• Obsessive Compulsive Disorder (OCD)


  A condition characterised by obsessions and/or compulsive behaviour. Obsessions are cognitive whereas compulsions are behavioural.
• The DSM-5 recognises OCD along with other disorders. These have common repetitive behaviours accompanied by obsessive thinking.
• Compulsion

  Behaviour (something you feel the need to do)
• Obsession

  About cognition (is something you think about)
• Cognitive characteristics of OCD

  • Obsessive thoughts
  • Cognitive coping strategies
  • Insight into excessive anxiety
• Obsessive thoughts

  For sufferers of OCD, these thoughts occur over and over again
• Obsessive thoughts

  • Fear of contamination, by dirt or germs
  • Fear of safety, by leaving doors or windows
  • Religious fears, from being immoral
  • Perfectionism, a fear of not being the best
• Cognitive coping strategies

  Sufferers of OCD adopt cognitive strategies to deal with their obsessions. For example, sufferers with religious obsessions may pray over and over, to reduce their feelings of being immoral.
• Insight into excessive anxiety

  Sufferers of OCD know that their obsessions and compulsions are irrational and experience selective attention directed towards the anxiety-generating stimuli (similar to the selective attention found in phobias).
• Emotional characteristics of OCD

  • Anxiety and distress
  • Accompanying depression
  • Guilt and disgust
• Anxiety and distress

  Unpleasant emotional experiences are due to powerful anxiety which is often paired with obsessions and compulsions. These emotions are overwhelming.
• Accompanying depression

  The anxiety experienced can often result in a low mood and loss of pleasure in everyday activities
• Guilt and disgust

  Obsessions are persistent and/or forbidden thoughts and ideas, which cause high levels of anxiety in OCD sufferers.
• Behavioural characteristics of OCD

  • Compulsions are repetitive
  • Compulsions reduce anxiety
  • Avoidance
• Compulsions are repetitive

  Sufferers will often feel compelled to repeat a behaviour (e.g. excessive hand washing)
• Compulsions reduce anxiety

  For example, the excessive hand washing is caused by an excessive fear of germs and bacteria and is therefore a direct response to the obsession.
• Avoidance

  Sufferers may attempt to avoid situations which might trigger compulsions. They try to manage their OCD for example, people who compulsively hand wash may avoid taking out bins or going outside where germs may be present. This can then interfere with their lives.
• Genetic explanations have focused on identifying particular genes which are implicated in OCD. It is known as a polygenic which means there are multiple genes that might be involved with the development of OCD.
• Candidate genes

  Researchers have identified genes, which create this vulnerability for OCD, called candidate genes.
• Genes linked to OCD

  • COMT gene
  • SERT gene
• COMT gene

  The COMT gene is associated with the production and regulation of the neurotransmitter dopamine. One variation of the COMT gene results in higher levels of dopamine and this variation is more common in patients with OCD, in comparison to people without OCD.
• SERT gene (also known as the 5-HTT gene)

  The SERT gene is linked to the neurotransmitter serotonin and affects the transport of the serotonin (hence SERotonin Transporter), causing lower levels of serotonin which is also associated with OCD (and depression)
• OCD is also known to be polygenic. This means that OCD is not caused by only one gene but multiple/ combination of genes that together increase vulnerability.
• Diathesis-stress model

  Certain genes leave some people more likely to develop mental disorder but is not certain. Instead, it is suggested that certain environments are most likely to trigger the development of the condition.
• What do biological psychologist rely on for their studies on genetics?

  • Twins/ family research
• Neural explanations for OCD

  • Neurotransmitters
  • Abnormal brain circuits
• Neurotransmitters

  Neural explanations suggest that abnormal levels of neurotransmitters, in particular serotonin and dopamine, are implicated in OCD.
• Serotonin

  The neurotransmitter serotonin is believed to play a role in OCD. Serotonin regulates mood and lower levels of serotonin are associated with mood disorders, such as depression. This abnormal level of serotonin may be caused by the SERT gene.
• Dopamine

  In addition, the neurotransmitter dopamine has also been implicated in OCD, with higher levels of dopamine being associated with some of the symptoms of OCD, in particular the compulsive behaviours.
• Basal ganglia

  The basal ganglia is a brain structure involved in multiple processes, including the coordination of movement. Patients who suffer head injuries in this region often develop OCD-like symptoms, following their recovery.
• Orbitofrontal cortex

  Another brain region associated with OCD is the orbitofrontal cortex, a region which converts sensory information into thoughts and actions. PET scans have found higher activity in the orbitofrontal cortex in patients with OCD.
• Heightened activity in the orbitofrontal cortex

  One suggestion is that the heightened activity in the orbitofrontal cortex increases the conversion of sensory information to actions (behaviours) which results in compulsions. The increased activity also prevents patients from stopping their behaviours.
• Brain functioning

  • Orbitofrontal cortex- responsible for anxiety
  • Caudate nucleus- acts as a filter suppresses messages from OFC
  • Thalamus- responsible for safety behaviour
• Person without OCD

  • OFC sends message- eg touching sticky table
  • Caudate nucleus- will suppress message from OFC
  • Thalamus- only responds to major worry
• Person with OCD

  • OFC sends message- touching sticky table
  • Caudate nucleus- damaged and unable to suppress or filter
  • Thalamus- responds to every message
  • This continues to happen over and over again
• Biological Treatments for OCD

  • Anti-depressants
  • Anti-anxiety
• Anti-depressant drugs

  OCD (and depression) is the result of low levels of the serotonin in the brain. SSRIs (selective serotonin re-uptake inhibitors) are one type of anti-depressant drug, which include drugs like Prozac. These drugs are available as liquid or capsules. They normally take about 4 months of daily use of SSRI to have an impact.
• Combining SSRI's with other treatments

  Drugs are normally used in combination with other therapies such as CBT (cognitive behavioural therapy) to treat OCD. The drugs reduce the emotional symptoms such as anxiety and depression, thus allowing the individual to engage in more effectively in CBT.
• Alternatives to SSRI's

  • Tricyclics- older type of anti-depressant which acts on various systems including the serotonin system where it has the same effect as SSRI
  • SNRI's (serotonin -noradrenaline reuptake inhibitors) have recently been used. They are a different type of antidepressant. SNRI's increase levels of serotonin as well as other different neurotransmitter-noradrenaline.
• Anti-Anxiety Drugs

  Benzodiazepines (BZs) are a range of anti-anxiety drugs, which include trade names like Valium and Diazepam. BZs work by enhancing the action of the neurotransmitter GABA (gamma-aminobutyric acid). GABA tells neurons in the brain to 'slow down' and 'stop firing' and around 40% of the neurons in the brain respond to GABA. This means that BZs have a general quietening influence on the brain and consequently reduce anxiety, which is experienced as a result of the obsessive thoughts.