Figure 4: Identification and characterization of mass excursions. (A) Raw excursion count (shown in black), E ( t ), along with null percentiles ranging from 50% to 99%. (B) The modular- ity during mass excursions was, on average, greater than the modularity during non-excursions, an effect that was likely driven by the increased number of strong functional connections. (C) We show functional network topologies for a non-excursion and an excursion. The module labels come from the Yeo2011 intrinsic connectivity network partition, which divides the brain into seven functional systems (and seventeen sub-systems not shown here). The systems cor- respond to control (CONT), default mode (DMN), dorsal attention (DAN), limbic (LIM), ventral attention/saliency (VAN), somatomotor (SMN), and visual (VIS) networks. (D) We compare the edge connection weight distribution for non-excursions with the distribution dur- ing excursions. During excursions the distribution is broader and includes values closer to ± 1. 42