Levodopa-Induced Dyskinesias and Dyskinesias-Reduced-Self-Awareness in Parkinson’s Disease: A Neurocognitive Approach

Levodopa-induced dyskinesias are one of the most common disabling motor complications in advanced Parkinson’s disease. The subjective perception of motor impairment is a clinical phenomenon that needs to be adequately analyzed. Indeed, the determination of patient dyskinesias-reduced-self-awareness (DRSA) and of its relationship to daily dysfunction is an important aspect of the debate on the gold standard for treatment. As the association with executive dysfunction is a matter of debate and we hypothesize it plays an important role in DRSA, we analyzed metacognitive abilities related to action monitoring and other factors, such as response-inhibition and “Theory of Mind,” which represent a novel explanation of the phenomenon. Moreover, we investigated whether and how a dysfunction in action monitoring related to the cingulo-frontal-ventral striatal circuit would be associated with DRSA using an event-related Go-NoGo fMRI experiment. Our findings suggest the presence of executive dysfunctions in DRSA pathogenesis, with a key leading role played by the cingulo-frontal network as part of a functionally impaired response-inhibition network.