Functional network changes in the hippocampus contribute to depressive symptoms in epilepsy

Abstract Purpose Our study aimed to investigate the functional connectivity (FC) between the hippocampus and other brain regions in epilepsy patients with depressive symptoms. Methods Epilepsy patients with and without depressive symptoms, assessed using the 17-item Hamilton Depression Rating Scale scores, were enrolled. Healthy volunteers were recruited as the control group. Resting state functional magnetic resonance imaging was performed, and the data were processed using Resting-State fMRI (DPARSFA2.0) software. The regional homogeneity (ReHo) values and the FC between the right hippocampus and other brain regions were analysed. Results The ReHo value of the cerebellum (particularly the left cerebellar hemisphere) was significantly lower in epilepsy patients than in healthy controls, and was lower in epilepsy patients with depressive symptoms (EP + DS group) than in those without depressive symptoms (EP-DS group, p  Conclusion The functional right hippocampus–cerebellum circuit might contribute to the pathogenesis of depressive symptoms in epilepsy, with the exception of brain areas associated with emotion such as the frontal and temporal lobes. Modulating the hippocampus–cerebellum circuit is a potential therapeutic strategy for epilepsy patients with depressive symptoms.