Neural

• Abnormal Levels of Neurotransmitters


  • It is thought that lower levels of serotonin are associated with OCD
  • Serotonin has a role in preventing the repetition of tasks
  • A lack of serotonin results in the loss of a mechanism that inhibits task repetition
  • Anti-depressant drugs that increase serotonin activity have been shown to reduce OCD symptoms
  • Dopamine levels are thought to be abnormally high in people with OCD
• Abnormal Brain Circuits


  • Several areas in the frontal lobes of the brain are thought to be abnormal in people with OCD
  • The caudate nucleus normally suppresses signals from the orbitofrontal cortex (OFC)
  • The OFC sends 'worry' signals to the thalamus
  • When the caudate nucleus is damaged it fails to suppress minor 'worry' signals from the OFC
  • The thalamus is alerted and confirms the 'worry' to the OFC creating a worry circuit, which could result in an obsession