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included all the vertices in the parcel. Temporal correlations of preprocessed time-series between the ROIs were calculated as the strength of func-tional connectivity. A binary undirected network for each subject was defined using a proportional threshold (top 9%), and the betweenness centrality of each parcel was calculated8-11). For the task dataset, we contrasted Stop success and Go success trials to reveal the brain activation for response inhibition.In total, 377 parcels were identified in the cortical surfaces. A ROI was defined for each parcel (Figure 1A). Figure 1B shows the centrality index across the ROIs for one representative subject. The subjects performed the stop-signal task in the scanner that comprised of Go trials and Stop trials (Figure 1C). Brain activation for response inhibi-tion was observed in several regions including the right IFC (Figure 1D). Two parcels (ROI 1 and Figure 1　Centrality map and activation in stop signal task. A. ROIs defined using areal parcellation. In total, 377 ROIs were defined (192 in left hemisphere and 185 in right hemisphere). The colors are randomly selected. B. Centrality map on ROIs of one representative subject. C. Stop signal task. A circle was presented at the center of the screen as a warning. In Go trials, a left- or right-pointing arrow was presented inside the circle. The participants were instructed to press a button indicating the corresponding side. In Stop trials, an arrow was first presented inside the circle, similar to Go trials. Then, the arrow was changed to an up-pointing arrow. The participants were required to withhold the response. D. Activated ROIs in the vIFC (Stop success minus Go success). LH, Left hemisphere; RH, Right hemisphere. Modified from Fujimoto et al.6).ROI 2) in the right vIFC were significantly acti-vated (ROI 1, t(19) = 5.42, p < 0.001; ROI 2, t(19) = 5.91, p < 0.001). There was no significant differ-ence in the task-related activity in the ROIs [t(19) = -0.71, P = 0.49]. ROI 1 was located more ventrally, whereas ROI 2 was located more dorsally in the vIFC (Figure 2A). The correlations between the centrality and the brain activity were calculated in the two ROIs. ROI 1 showed significant correlation (r = 0.62, p = 0.003) (Figure 2B), whereas ROI 2 did not (r = -0.01, p = 0.97) (Figure 2C). The difference in the correlation was also significant (z = 2.15, p = 0.032). For ROI 1, which was significantly correlated, the correlation between activation and SSRT was significant (r = -0.50, p = 0.026) (Figure 2D). However, the correlation was not significant between centrality and SSRT (r = -0.01, p = 0.95).In the ventral parcel in the vIFC, the correlation between centrality and brain activity during 209