Pathophysiology of Gait and Posture in Progressive Supranuclear Palsy

The main hypothesis is that the gait and postural deficits in the Caribbean form of PSP may be associated with a dysfunction of the cerebral cortex, as they result from sub-cortical involvement in classical forms. The investigators will characterize the gait and posture with a force platform to collect biomechanical gait parameters, coupled with the kinematic and electromyographic (EMG) study. Then the investigators realize a multimodal imaging study \[structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI)\] that allow us to determine if a correlation can be found between the clinical characteristics of postural control and walking on one hand, and morphological changes and structural MRI changes in cortico-subcortical pathways on the other hand. The study of performance on neuropsychological tests, registration of ocular movements and the analysis of functional cortical activity will complete our multimodal approach. A better understanding of these disorders is expected to propose new drug treatment and rehabilitative strategies.