Figure 11. Topological structure of the network of physiological interactions reconstructed during the rest (R), mental arithmetic (M) and serious game (G) experimental conditions.

Graphs depict significant directed interactions within the brain (purple arrows), body (red arrows) and brain-body (green arrows) sub-networks. Directed interactions were assessed counting the number of subjects for which the conditional Granger causality (F_i→j|s) was detected as statistically significant using OLS (A–C) or ANN (D–F) in the estimation process. The arrow thickness is proportional to the number of subjects (n) for which the link is detected as statistically significant.