Reproducibility of Activation Map across Sessions and Groups
Table 1 describes the spatial overlap across sessions and groups using dice coefficients. In general, the reproducibility of group-level maps was moderate. The alerting network had the highest dice coefficient across sessions (HC: 0.59, PD:0.46) and groups (Session 1: 0.62, Session 2: 0.49). The group-level reproducibility for the executive network was the worst, except that the PD group’s spatial overlap across sessions was about half (dice = 0.46). The spatial overlap across groups for the executive network was unsatisfactory, especially for the second session (dice = 0.15). In the supplementary material (Table S5), we also provide results for dice coefficients using varying thresholds, which indicated a similar finding. In addition, we conducted a region-based analysis using the Schaefer-Yeo atlas to help readers better grasp the reproducibility of attention networks across brain regions. As shown in Figure 2 , the reproducibility at the region level was poor. The region-based visualization provided a coarse summary of the attention networks across groups and sessions. However, it should be noted thatFigure 2 is for illustration purpose as averaging activations at the region level might be too coarse to reveal the real spatial activations.
Table 1. Dice Coefficients of the Three Attention Networks across Sessions and Groups