THE PATTERNS OF BIOELECTRICAL ACTIVITY OF MOTOR UNITS IN DIFFERENT FORMS OF PARKINSONISM

The correlation between the motor units activity patterns and clinical forms of parkinsonism has been investigated by means of surface elect romyography. Grouped electromyogram, characteristic of parkinsonism sh aking was found to be generated on the basis of double, triple dischar ges of the motor unit (doublets and triplets), or long-term synchroniz ation of motor units discharges as well as by means of simultaneous re cruitment of both above mechanisms. Stationary electromyogram, charact eristic of akinetic-rigid form, was shown to correlate with asynchrono us, stable astivity oy the motor units that impulse at the frequencies 9-10 Hz. Mixed forms of parkinsonism (shaking-rigid and rigid-shaking ) were characterized by large amount of the motor units that impulse w ith high variability of interspike intervals and have a tendency to fo rm doublets (unstable motor units). Different combinations of doublets , triplets and logn-term synchronization of motor units with stable, a synchronous motor units activity were also found in mixed forms of par kinsonism.