Cortical processing of proprioceptive input is different in idiopathic Parkinson's disease and multiple system atrophy

Aims: Processing of proprioceptive input is altered in idiopathic Parkinson's disease (IPD), and it has been hypothesized that this may contribute to bradykinesia. Yet it is not entirely known which central neuronal pathways are the ones that are impaired. Transcranial magnetic stimulation (TMS) can contribute to examining cortical loops involved in proprioceptive processing. Objectives: To test whether proprioceptive input mediated by muscle vibration does influence cortical excitability in IPD less than in control subjects and to examine whether the hypothesized changes are specific for IPD. In theory, these c…