Neuroimaging study of hippocampal subregion involved in post-traumatic stress disorder / 中华行为医学与脑科学杂志

ABSTRACT

The hippocampus plays an important role in fear learning and memory processing.It is a key brain area in the pathogenesis of post-traumatic stress disorder (PTSD). Neuroimaging studies have confirmed that the hippocampal structure and functional connectivity of patients with PTSD are abnormal, but the changes in hippocampal subregions are still unclear.The results of brain structure studies showed that the cornu ammonis and dentate gyrus atrophy in adult PTSD patients and the symptom of re-experience may be related to pattern separation dysfunction caused by reduced dentate gyrus neurogenesis.Among children diagnosed with PTSD, there is no significant change found in cornu ammonis and dentate gyrus, while atrophy in presubiculum was observed, which could result in fear extinction and deficits in episodic memory.The alteration of hippocampal volume in PTSD may have a gender-specific lateralization phenomenon.The results of brain function studies show that the functional connectivity of hippocampal subregions in PTSD patients is selectively damaged, especially the connectivity with key brain regions in the default mode network is reduced.This article systematically reviews the structural and functional connectivity changes of hippocampal subregions in patients with PTSD from the perspective of neuroimaging, in order to promote the understanding of the pathogenesis of PTSD and identify the therapeutic targets of hippocampal subregions.