Figure 8. One-hour paired-stimulation conditioning session at 20 ms delay. a, Schematic of conditioning session with 20 ms delay using rack-mounted equipment while Monkey U was in the booth for 1 h. Left,Cortical positions of A (purple), B (green), and C (orange) sites relative to the central sulcus (dotted line). b, StTA of A→B EP before (blue) and after (red) conditioning at current amplitude denoted by black box in c. Diamonds indicate peak and trough used to calculate amplitude plotted in c. Inset shows magnified view of the early part of the EP; black lines and arrows indicate the slope of the first response phase. c, Stimulus–response curve of A→B EP before (blue) and after (red) conditioning. Black box is current amplitude, 400 μA depicted in b. Inset, Stimulus–response curve for slope of the first phase with the same color scheme. d, Percentage change in EPs from A, B, and C to all other sites where there was a response, as in Figure 7. Fifteen EP sites showed statistically significant changes, either increases or decreases, although none was as large as for the A→B EP. Significant EPs were A→C, A→L6, A→L8, A→L9, A→L15, B→L1, B→C, B→A, B→L4, B→L10, B→L13, C→A, C→L6, C→B, and C→L11.