[Relationship between static sensitivity and spontaneous muscle receptor activity].

Study of the spontaneous impulse activity of 193 m. triceps receptors in cats revealed that the units of dynamic type characterized by high dynamic sensitivity have the mean firing rate lower than positional those. The higher is the mean firing rate at 10-mm muscle stretching, the higher is the probability that these receptors have spontaneous discharges of higher mean frequency. A close linear correlation exists between the mean frequency of the receptors spontaneous discharges and the value of their static responses to stretching. The data obtained suggest that the spontaneous activity is inherent in receptors capable of responding to an increased resting tone of the passive muscle spindle.