Early-occurrence of manual motor blocks in Parkinson's disease: a quantitative assessment

Augmented motor blocks in internally-cued performance should be recognized as a frequent, distinct and generalized feature of PD. Whereas the gait disorder is regarded as characteristic of the advanced stage of PD, our findings suggest that the basic defect in internal rhythm formation can be detected by sensitive measurement tools from the early stages of the disease. In addition, the methodology developed in this study to quantitatively measure manual motor blocks may be a useful tool for future development of therapeutic regimens for this debilitating aspect of motor dysfunction in PD.