NEURAL EXPLANATION

• Brain areas believed to be involved in OCD include the orbitofrontal cortex (OFC) and the thalamus. The thalamus is a brain area whose functions include cleaning, checking and other safety behaviours.
• Neurotransmitters


  It is thought that serotonin and other neurotransmitters help the functioning of the OFC and the caudate nucleus.
• OFC - sends worry signals to thalamus

  Thalamus - sends filtered version of danger back

  Caudate nucleus - monitors signals
• Brain dysfunction:

  1. People with OCD have damage to their caudate nucleus which is in the basal ganglia.
  2. The orbitofrontal cortex sends worrying signals to the thalamus.
  3. The caudate nucleus fails to turn off the 'worry signals' from the orbitofrontal cortex.
  4. The thalamus sends message about incorrect danger levels back.
• HU (2006) compared serotonin activity in 169 OCD sufferers and 253 non sufferers, finding serotonin levels to be lower in the OCD patients, which supports the idea of how low levels of serotonin being associated with the onset of the disorder.
• RAUCH (2000) - reviewed studies of OCD using PET/FMRI and MRI scans to find consistent evidence of an association between the OFC and OCD symptoms.
• Strengths:

  • Useful for developing future hypotheses and treatments focussed on serotonin levels.
  • Concurrent validity - research to support theory.
• Weaknesses:

  • Reductionist - only focusses on internal processes but this could be useful.
  • Time consuming and expensive to use scientific equipment.
  • Other explanations - genetic, DSM.