Diathesis – this refers to a genetic vulnerability someone may have to an illness
Stress – this refers to environmental factors that may trigger an illness
The diathesis-stress model suggests people may have a gene that puts them at risk of developing OCD, but the disorder only occurs if there is an environmental trigger
Neural explanations - chemical
Neurotransmitters are chemicals that transmit information from one neurone to the next at synapses
Neural explanations - chemical
Serotonin is a neurotransmitter that regulates mood. Low serotonin levels cause OCD
Neural explanations - physiological
The basal ganglia regulates the initiation of movement and is connected to motor areas in the brain - involved in OCD
Neural explanations - physiological
Damage to the basal ganglia causes OCD
Neural explanations - physiological
Some cases of OCD seem to be linked with impaired decision making, which could be caused by abnormalities in the lateral frontal lobes of the brain (frontal lobes are responsible for logical thought and decision making)
Neural explanations - physiological
An area called the left parahippocampal gyrus, which is associated with the processing of unpleasant emotions has been linked to OCD
