Movement disorders--limb movement and the basal ganglia. The primary concern of this article is to review experimental methods that may lead to a better understanding of the functional role of the basal ganglia in the control of movement. Two models of basal ganglia impairment are considered: Parkinson's disease and Huntington's disease. The review focuses primarily on akinesia and bradykinesia because they are key abnormalities of basal ganglia dysfunction. In general, through electromyography and kinematic analysis of movement, it may be possible to characterize specific movement disorders. Specifically, if damage sustained by the central nervous system is traced to a certain structure, it may provide insight on the extent of involvement and functional role of that structure in the control of movement. Much of the data reviewed suggests that the basal ganglia may play a specific role in the initiation and regulation of force control. 