Fast repetitive force changes in hemiparetic and cerebellar patients.

A method for the continuous registration of rapid isometric force changes was investigated in 24 healthy control persons, 10 hemiparetic patients and 10 cerebellar patients. Though the selection of both patient groups involved comparable deficits with respect to the number of force changes attained, the analysis of the underlying force-velocity patterns revealed considerable differences in the performance of hemiparetic and cerebellar patients. Hemiparetic patients showed gross deficits in both the force increasing and decreasing phases. In contrast to this, most cerebellar patients were able to release force as fast as normal controls, while marked slowness was only found for the force increasing phases.