Fig. 3.

Populations responses in monkey M and N. (A, B, F, and G) PSTHs for responses of S1 and M1 neurons for synchronous (shaded yellow) and asynchronous (gray) sessions. Firing rates are normalized to represent z-scores. In all plots, only neurons with significant excitatory responses to physical touch are shown. The neurons are shown in ranked order from the weakest (Top) to the strongest (Bottom) responses. Color plots show the same set of neurons for Vonly from E1 (Top), Vonly from E2 (Middle), and V+P (Bottom). Vertical green lines represent onsets and offsets of the stimuli. Average PSTHs for the population are indicated by black lines superimposed on the color plots. Asterisks indicate significant differences between response rate and baseline by Wilcoxon text: *P < 0.05, **P < 0.01, and ***P < 0.001. (C, D, H, and I) Average and cumulative PSTHs for the population for monkey M (C and D) and monkey N (H and I). Pink lines represent the mean and SD. (E and J) Distribution histograms for the difference in response onsets between V+P sync trials and Vonly trials for S1 (Upper) and M1 (Lower) neurons. Positive values indicate that V+P sync responses occurred earlier than Vonly responses. Red dashed line is the Gaussian fit. Arrows mark mean values. Mean and SEM are indicated.