Deteriorating neural connectivity of the hippocampal episodic memory network in mTBI patients: A cohort study

摘要

The current study investigated topographies and causality profiles of left hippocampus-related brain systems identified with resting state functional correlations in mild TBI as well as healthy individuals. We found a set of significantly connected brain regions (nodes) involved in the left hippocampal intrinsic network and altered causality profiles among the identified nodes. Functional connectivity analysis showed that the hippocampal network concerning episodic memory in mild TBI survivors (mTBI) became increasingly larger than that in normal controls, especially the medial frontal gyrus (MeFG), middle frontal gyrus (MFG), and temporo-parietal conjunction area. Granger causality analysis (GCA) illustrated increased bilateral causal connectivity and ipsilateral interaction in the right hemisphere, which was in contrast to intensive ipsilateral causal connection in the left hemisphere in normal controls. We postulated that the dysfunctioned hippocampus and ineffective compensation strategy resulted in a weakening episodic memory in mTBI patients.