[Influence of adequate stimulation on the impulse electrical activity of isolated frog muscle spindles].

Impulse activity of an isolated frog muscle spindle was investigated using mechanical stimulation of various amplitude, rate and form. It is found out that firing frequency during linear-increasing stimulation is determined by the amplitude of the stimulus and alteration of firing frequency by the rate of the stimulation increase. At sinusoidal stimulation the impulsation "repeates" the form of the stimulus, i.e. the muscle spindle is influenced not only by its amplitude or rate, but also by its acceleration. The sensitivity to accelerations may depend on changes in discharge threshold during alteration of the tension rate change.