[Experimental research and new concepts of the role of the cerebellum].

It has been discovered recently--especially thanks to the experimental research on animals--that cerebellum is not only a co-ordinator of the motor functions but that it also participates in the higher functions of the central nervous system. In this research, models with genetically determined cerebellar degeneration (Lurcher, pcd. staggerer, hot-foot, weaver) or originally healthy animals after partial or complete artificial destruction of cerebellum are often used. The animals can be tested by specific methods of motor learning (rotating steel grid, rotorod, round wooden beam, bridge, coat-hanger, horizontal crossbar, vertical and inclined grid, ladder), spatial learning (Morris water maze, radial maze, hole board) and discriminative learning-type of passive avoidance (step through and step down). The experiments result in conclusion that an injury or degeneration of the cerebellum are associated with worse motor skills and cognitive functions. Nevertheless, the disorders of cerebellum do not prevent from motor learning completely: motor possibilities of Lurcher and hot-foot mutants can be improved by training in spite of the fact that they never reach the same level of motor abilities of healthy controls. Drug therapy of cerebellar degeneration and substitution of lost cells by transplantation are in the phase of new experiments.