Top-down control of cortical gamma-band communication via pulvinar induced phase shifts in the alpha rhythm
Fig 8
In bidirectional networks the alpha phase difference determines the direction of communication.
(A) Schematic of the model with bidirectional connections between both areas. (B) With bidirectional connectivity the gamma coherence has peaks at two distinct alpha phase differences (solid line; baseline is represented by dotted line). (C) For an alpha phase difference of -90° Granger causality from area 1 to area 2 (red) is much stronger. (D) For an alpha phase difference of 90° the granger causality from area 2 to area 1 (blue) dominates. (E) At zero alpha phase difference Granger causality is equal in both directions (red, from area 1 to area 2, blue from area 2 to area 1) and shows a clear peak in the gamma band. Data was averaged over 10 trials, shaded areas represent the standard error of the mean (SEM).