A cross-sectional and longitudinal study of changes in complex networks related to brain function in temporal lobe...

The aim of this study was to investigate the changes in complex networks of brain functions associated with LEV treatment and the neural mechanisms underlying the effects on executive functions. Patients with TLE, including both users and nonusers of LEV, were included in this study along with healthy controls. Rs-fMRI and an attentional network test (ANT) were performed, and 9 of the 23 patients not taking LEV were selected for LEV intervention and followed up for 18 months. Rs-fMRI and ANT were reviewed, and graph theoretic analyses were applied to investigate the changes in their topological properties. Both the LEV and HC groups showed improvements in executive function compared with the non-LEV group. At the global level, significant group differences in global efficiency and characteristic path length were observed among the three groups. At the nodal level, compared with the HC and non-LEV groups, the LEV group presented multiple differential nodes with different topological properties in the parieto-occipital lobe and frontal lobe. The TLE-LEV group had multiple differential nodes in the parieto-occipital lobe and frontal-temporal lobe compared with the TLE-N group. Notably, the LEV group's betweenness centrality of the superior frontal gyrus and dorsolateral and executive functions was significantly positively correlated with the correlation analyses. Changes in the topological properties are a key effect of LEV administration. This finding improves our understanding of the neural mechanisms by which LEV improves cognitive functioning.