Neural

• Neural explanations of OCD focus on neurotransmitters as well as brain structures.
• Neural explanations suggest that abnormal levels of neurotransmitters, in particular serotonin and dopamine, are implicated in OCD.
• Neural explanations also suggest that particular regions of the brain, in particular the basal ganglia and orbitofrontal cortex, are implicated in OCD.
• 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.
• Support for the role of serotonin in OCD comes from anti-depressants which increase the level of serotonin and are effective in treating patients with OCD.
• A drop in serotonin causing changes in mood, which may explain some of the symptoms of OCD.
• Some cases of OCD like hoarding, document impaired decision-making which may be caused by changes in the brain.
• Abnormal functioning in the frontal lobe is linked to poor decision-making.
• Evidence suggests the left parahippocampal gyrus is associated with processing issues in patients with OCD.
• Two brain regions have been implicated in OCD; the basal ganglia and orbitofrontal cortex.
• The basal ganglia is a brain structure involved in multiple processes, including the coordination of movement.
• Max et al (1994) found that when the basal ganglia is disconnected from the frontal cortex during surgery, OCD-like symptoms are reduced.
• The orbitofrontal cortex is a region which converts sensory information into thoughts and actions.
• PET scans have found higher activity in the orbitofrontal cortex in patients with OCD.
• One suggestion is that the heightened activity in the orbitofrontal cortex increases the conversion of sensory information to actions (behaviours) which results in compulsions.
• Serotonin regulates mood.

  Lower levels of serotonin are associated with mood disorders, such as depression and in some cases of OCD, they are associated with the reduced levels of serotonin.

  This could be caused by a faulty SERT gene.
• Evidence for the role of serotonin in OCD comes from research examining antidepressants(SSRIs).
• Piggott et al(1990) who found that drugs which increase the level of serotonin in the synaptic gap are effective in treating patients with OCD.
• Low levels of Serotonin= OCD
• 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 when, for example a patient is asked to hold a dirty item with a potential germ hazard.
• Increased activity in the orbitofrontal cortex= OCD
• Basal Ganglia:

  Cluster of neurons at the base of the forebrain, which is involved in multiple processes including the coordination of movement.
• Patients who suffer head injuries in this region of ten develop OCD like symptoms.
• Damage to the Basal Ganglia results in OCD