# Multi-Graph Assessment of Temporal and Extratemporal Lobe Epilepsy in Resting-State fMRI
## 3 Results
### Hub Probabilities in Regions of Interest  
The threshold on the hub probability of the ROIs is defined within each of the three groups and it is different for the three types of connectivity metrics, resulting in 9 different thresholds. In the Pearson correlation graph network analysis, the thresholds that were used to identify the hubs of each group were: \(\text{p}_{\text{R,ETLE}}>0.55\), \(\text{p}_{\text{R,TLE}}>0.48\), and \(\text{p}_{\text{R,C}}>0.56\). According to those thresholds, the hub regions presented in all groups in both hemispheres were as follows: the superior frontal gyrus (SFG), the superior parietal gyrus (SPG), the postcentral (PostCG) and precentral gyrus (PreCG), the precuneus (PCUN), the middle temporal gyrus (MTG), and the lateral aspect of the superior temporal gyrus (STGlat). In the left hemisphere, all groups have a hub with the supramarginal gyrus (SMG), and in  
Figure 2: The global topological features presented significant differences between the three groups for all the types of graphs: Pearson correlation, MI, and Granger causality, for the various density levels. Blue lines correspond to the control group, orange to the TLE group, and green to the ETLE group. Statistically significant differences (\(p<0.05\)) are presented with the asterisk (\(\lx@paragraphsign\)) symbol. Red asterisk: difference between TLE and ETLE; blue asterisk: difference between ETLE and control; black asterisk: difference between TLE and control. the right hemisphere, the middle occipital gyrus (MOG) and the superior temporal sulcus (STS) (Figure 3). The highest probabilities in all groups are reported in Appendix C.  
We observed a hub reorganization between the control group and the patients, explained through the differences in hub probabilities. The probability distribution indicated that the superior occipital gyrus (SOG) was identified in the control group with a hub probability of more than 61% in both hemispheres (61.9% the left SOG, 71.4% the right SOG), while the same probability was less than 36% for the TLE group (35.7% the left SOG, 32.1% the right SOG) and less than 50% for the ETLE group (37.5% the left SOG, 50% the right SOG). Furthermore, the bilateral Cuneus (CUN) demonstrated decreased probability in both patient groups compared to controls. Specifically, the left CUN hub probability was 66.7% in controls, 46.4% in TLE patients, and 31% in ETLE patients, while the right CUN hub probability was 71% for the controls, 42.9% in the TLE, and 50% in the ETLE groups. Another deviation that was observed in the patients' hubs was in the left inferior occipital gyrus (IOG), where the control group showed a hub probability of 76.2% while the patient groups were significantly lower (39% for the TLE patients, 43.8% for the ETLE patients). Finally, the paracentral gyrus (ParaCG) was deemed as a region with a key role in the ETLE graphs, with 68.75% hub probability bilateral, while the bilateral hub probability for the control group was 38% and for the TLE was lower than 50% (46.43% in the left hemisphere and 42.86% in the right). Regarding the MI graph networks, most of the hub regions did not display significant differences among the three groups (Figure 4). In the MI graph analysis, the thresholds that corresponded to the hub probabilities for each of the three groups were: p\({}_{\text{RTLE}}>0.56\), p\({}_{\text{RTLE}}>0.48\), and p\({}_{\text{RC}}>0.49\). The highest probabilities in all groups are reported in Appendix C. The brain regions found as hubs in both hemispheres in all groups were more posterior regions, mainly in the occipital lobe as well as the superior parietal gyrus and the posterior central gyrus. The hubs presented unilaterally in all groups were the left CUN and the right ParaCG. Interestingly, the right CUN was presented in most patients' MI graphs with higher hub probability values compared to the control group (hub probability was 60.7% in the TLE and 81% in the ETLE group, but only 47.6% in the controls).