Psychopathology
Biological Approach to Explaining OCD:
Genetic Explanations:
The COMT Gene:
may contribute to OCD
produces COMT which regulates the production of dopamine which is implicated
with OCD
one allele of the COMT gene is more common in OCD patients than non-OCD
patients
The SERT Gene:
the SERT gene affects the transport of serotonin causing lower levels of it
low levels of serotonin are associated with OCD
Diathesis-stress:
there must be a stressor to trigger the ‘gene’ to suffer
some people may have the COMT or the SERT gene but not suffer the disorder as it
has not been triggered by an environmental stressor
Neural Explanations:
Abnormal Levels of Neuro-transmitters:
OCD is associated with abnormally high dopamine levels
it is also associated with abnormally low serotonin levels
Abnormal Brain Circuits:
certain areas in the frontal lobe of the brain are thought to be abnormal in people who
suffer from OCD
the caudate nucleus suppresses minor signals from the orbitofrontal cortex
the orbitofrontal cortex sends worry signals about germ hazards etc
if the caudate nucleus is damaged, it cannot suppress these minor worry signals and
the thalamus gets alerted of worry from the OFC, which in turn sends signals back to
the OFC, acting as a worry circuit
serotonin and dopamine are linked to this - low levels of serotonin can cause it to
malfunction and high levels of dopamine can lead to over-activity
Biological Approach to Explaining OCD:
Genetic Explanations:
The COMT Gene:
may contribute to OCD
produces COMT which regulates the production of dopamine which is implicated
with OCD
one allele of the COMT gene is more common in OCD patients than non-OCD
patients
The SERT Gene:
the SERT gene affects the transport of serotonin causing lower levels of it
low levels of serotonin are associated with OCD
Diathesis-stress:
there must be a stressor to trigger the ‘gene’ to suffer
some people may have the COMT or the SERT gene but not suffer the disorder as it
has not been triggered by an environmental stressor
Neural Explanations:
Abnormal Levels of Neuro-transmitters:
OCD is associated with abnormally high dopamine levels
it is also associated with abnormally low serotonin levels
Abnormal Brain Circuits:
certain areas in the frontal lobe of the brain are thought to be abnormal in people who
suffer from OCD
the caudate nucleus suppresses minor signals from the orbitofrontal cortex
the orbitofrontal cortex sends worry signals about germ hazards etc
if the caudate nucleus is damaged, it cannot suppress these minor worry signals and
the thalamus gets alerted of worry from the OFC, which in turn sends signals back to
the OFC, acting as a worry circuit
serotonin and dopamine are linked to this - low levels of serotonin can cause it to
malfunction and high levels of dopamine can lead to over-activity
