Figure 5.

A, Longitudinal distribution of the mean amplitude of sinusoidal (and tonic) cord dorsum potentials during scratching for five cats. B, Laminar distribution of intraspinal field potentials during scratching. The sinusoidal CDPs were used to average the intraspinal EFPs recorded at the indicated depths. The graph represents the grand average for the amplitude distribution of the EFPs versus the depth of recording obtained from seven cats. The histological reconstructions for the electrode trajectories are illustrated for four cats. The magenta circles indicate the depth in which the EFPs of maximal amplitude were obtained. C, Simultaneous recordings of sinusoidal CDPs, single interneuron (INT), and MG and TA electroneurograms. D, Correlation between the cycle of sinusoidal CDPs (CDP–CDP cycle) and the cycle of the interneuronal firing (INT cycle). E, Histological reconstructions of the L6 lumbar spinal cord for three cats. The symbols represent the location of 18 interneurons. For clarity, the symbols were colored.