[Characteristics of program-type movements in lesions of various cerebellar systems in man]

Mechanisms of participation of two main cerebellar systems, i.e. lateral and intermedial ones, in control of preprogrammed voluntary movements have been studied in man. Related movements were analyzed in healthy subjects and in groups of patients suffering from different forms of cerebellar and pyramidal disorders. The task consisted of series of dorsal or plantar flexions of foot of increasing amplitudes with minimal amplitude of neighbouring movements. It was shown that both the lateral and intermedial cerebellar lesions were followed by deep alterations in program motor control mechanisms, however the intensity and specific features of alterations in two groups under study differed significantly. In patients suffering from pyramidal lesions the ability to perform programmed movements was lost completely.