Creativity is a multifaceted and complex construct based on diverse neurological, cognitive and psychological processes and a certain balance must be present between them to enable creative drive. In PD patients, the balance can be altered by the disease and by the dopaminergic treatment. Indeed, dopaminergic medication seems to influence all goal-directed behaviors with a reward component, contrary to the disease itself, which leads to loss of motivation related to mesolimbic dopaminergic denervation. This explains the continuum of observed behaviors in PD, with awakening of the desire to undertake pleasant activities, including creative ones, if the mesolimbic system is rich in dopamine, and extinction of the desire to undertake pleasant activities if the mesolimbic system is lacking dopamine.
PD patients with fluctuations represent a very powerful model allowing us to study opposite psychiatric states intra-individually in both levodopa dopaminergic ON- and OFF-drug state and to abstract several interpersonal variables. Using different well-established and newer neuropsychological assessments, we aim to further explore relevant cognitive processes, like divergent thinking and to correlate them with other cognitive processes such as fluency or inhibition control as well as personality traits. A potential link to hallucinations based on a phenomenon called pareidolia, an illusory perception of patterns in natural landscapes and structures, is also explored. Those results combined with resting state fMRI may contribute to a better understanding of the neuronal mechanisms underlying creative behaviour. Our goal is to identify regions with symptom-specific neuronal activity patterns that might help us to enhance our understanding of the pathophysiological mechanisms underlying neuropsychiatric symptoms and serve in the future to guide individualized treatment interventions.