For weak inter-areal coupling strengths, out-of-phase lockings of local periodic oscillations give rise to a family of “unidirectional driving” effective motif. The figure shows dynamics and corresponding effective connectivities for fully symmetric structural motifs with (panels A–B) or (panels C–D) areas. A: the dynamics of interacting areas (green and orange colors) is illustrated by “LFPs” (left, top row) and representative spike trains (left, middle row, two cells per each area) from the network model (horizontal bar is , vertical bar is ), as well as by matching rate traces (left, bottom row) from the rate model (arbitrary time units). The right sub-panel reports the associated effective connectivity measured by Transfer Entropy (TE), evaluated from “LFPs” time-series, for all possible directed interactions (indicated by colored arrows). Boxes indicate the interquartile range and whiskers the confidence interval for the estimated TEs. TEs above the grey horizontal band indicate statistically significant causal influences (see
Methods
). B: to the right of the corresponding box-plot, effective connectivity is also represented in a diagrammatic form. Arrow thicknesses encode the strength of corresponding causal interactions (if statistically significant). Below this effective motif, a second motif in the same unidirectional driving family is plotted (with a smaller size), corresponding to another motif version with equivalent overall topology but reversed directionality. The parameters used for are, for the network model: , ; and for the rate model: , , . C: this panels reports similar quantities as panel A, but now for a structural motif with areas (green, orange and light blue colors). Effective connectivity is now measured by partialized Transfer Entropy (pTE; see
Methods
), in order to account only for direct causal interactions. D: the six effective motifs of the unidirectional driving family for are also reported. The parameters used for are, for the network model: , ; and for the rate model: , , .