Figure 5.

Positive PPI between the left SPL (seed) and the response regions, right FEF, right SEF, right SMG, and left visual cortex, for compensated trials versus no-step slow trials in a representative individual. The compensated trials are in red, and the no-step slow trials are in black. The plots represent the regression of the time series of the seed region (left SPL) on the time series of the responding region. The lines illustrate the regression (red line, compensated trials; black line, no-step slow trials). The dots are the observed data (residual values) adjusted for main effects (red dots, compensated trials; black dots, no-step slow trials). The dots are the residual fMRI time series data (activation factored out) for every single time point in the recorded fMRI time series. For each participant, the slope of line plotting residual activity in the seed against residual activity in the response region was calculated for compensated and no-step slow trials. The difference in the slopes is plotted in the histograms presented in the inset. Positive values represent larger slopes for compensated than no-step slow trials. This was done in order to visualize the data across subjects.