EFFECTS OF GAMMA BLOCKING ON MUSCULAR ACTIVTY AND THEIR RELATION TO MYASTHENIC STATE

Since the discovery of the gamma system by Leksell<SUP>11)</SUP>, its role on voluntary muscular contraction has been emphasized by many workers, <SUP>1-7, 10, 14)</SUP>. The papers reported by Matthews and Rushworth on the selective blocking of small motor fibers by procaine<SUP>12, 13)</SUP> presented the possibility to study their defect symptoms experimentally produced on human subjects.<BR> In the present paper the blocking effect of gamma fibers on voluntary contraction was studied by mathematical analysis of the discharge pattern of a single neuromuscular unit (NMU) and EMG wave form. In addition, the same analysis was applied to muscles of myasthenia gravis and its motor symptoms were discussed from the view point of the gamma activity.