Exploration of Mesocorticolimbic Pathway in Impulse Control Disorders in Parkinson's Disease: Study Using Tensor Diffusion Imaging and Tractography.

Impulse control disorders (ICD) are frequent in Parkinson's Disease. Neurobiological substrates of these symptoms are largely unknown. The investigators aim to explore mesocorticolimbic pathway in Parkinson's disease patients with impulse control disorders (ICD) using an MRI technique called tensor diffusion imaging (DTI). More precisely, the main purpose is to demonstrate that fractional anisotropy (FA) (data obtained with DTI) in the ventral tegmental area (VTA) is different between patients with ICD and patients without ICD. Secondary objectives are to demonstrate a difference in volume of VTA, in FA in others structures included in reward system (prefrontal cortex, nucleus accumbens, amygdala), and in number of fibers between VTA and the other structures of reward system between this two groups. Other objective is to measure and compare these same variables between Parkinson's patients and healthy controls. We hypothesized that a denervation of mesocorticolimbic pathway predisposes Parkinson's patients to ICD.