In contrast to the marked grey matter volume decline concentrated in the affected MTL, we found widespread functional connectivity alterations within the DMN in patients with mTLE in comparison to healthy controls (FC-PLS, left mTLE p < 0.001; right mTLE p < 0.009, see Fig. 1B and Table S1 for BSRs). Interestingly, we found the same characteristic differences in both patient groups. First, in comparison to healthy controls, patients with mTLE showed reduced functional connectivity between the affected MTL and the posterior part of the DMN. That is, of the 23 connections that were significantly increased in controls relative to left mTLE patients, 11 involved ROIs of the MTL and the posterior part of the DMN. A similar pattern was observed in the comparison of controls with right mTLE patients in that 6 of the 15 increased connections involved those ROIs. In contrast, very few such connections were increased in patients relative to controls (1 of 12 for left mTLE, 0 of 9 for right mTLE). Specifically, controls show strong interhemispheric connectivity between bilateral retrosplenial cortices and hippocampi, whereas patients
