A, the following traces are shown: PTNfl – activity of a PTN from the forelimb representation of the motor cortex; Tilt – tilt of the platform; BdF – lateral position of the body; FHL, FHR – contact forces under hindlimbs, left and right; FFL, FFR – contact forces under forelimbs, left and right. B, characteristics of neuronal activity: the histogram of spike activity in the tilt cycle (black thick line); 1st harmonic of Fourier image (red line) with its amplitude (f1) and the value of modulation (M1) indicated; mean frequency in the tilt cycle (f0, green line); preferred phase of the discharge (PPh, arrow). C, areas of recording within representations of the fore- and hindlimb in the left motor cortex (1 and 2, respectively; Cru, cruciate sulcus; Pcd, postcruciate dimple). Microelectrode entry points into the cortex (cortical plate openings through which penetrations were made) are combined from two cats and shown by black circles.