[The characteristics of the latent periods of movements in cats during the differentiation of tonal and amplitude-modulated signals with changes in the modulation from high frequencies to low].

The latent periods of the forepaw movements of cats were studied in the course of differentiation task performance. Pure tones and amplitude-modulated stimuli had to be differentiated. It was found out that the mean latency of motor responses to pure tones was significantly higher than that of responses to modulated signals. The latencies to the applied stimuli did not differ in the simple task (without differentiation). The latencies were influenced not only by the absolute values of modulation frequency but also by the frequency shift in successive experiments. Lowering modulation frequency decreased the latency. This effect was especially expressed around the values of 205-207 and 33-34 Hz.