 STN DBS on the other hand may have a more direct effect on obsessions and compulsions. The limbic STN, like the ventral striatum, is in a unique position to influence behavioural outputs of cortico-striatal-thalamo-cortical circuitry. This is because the STN receives a direct projection from right inferior frontal cortex which acts as a hyperdirect pathway, activation of which overrides neural processing in the direct cortico-striato-pallido-thalamic pathway. This results in the inhibition of ongoing, planned acts and thoughts. Investigators therefore hypothesise that, via this inhibitory mechanism, stimulation of STN neurones enables OCD patients to interrupt their repetitive thoughts and actions resulting in a decrease in obsessions and compulsions. 