认知正常与轻度认知障碍老年人海马亚区与序列位置效应关系的研究

Association of hippocampal subfields and serial position effect in the elderly with normal cognition and mild cognitive impairment

目的:研究认知正常与轻度认知障碍老年人海马亚区与序列位置效应的相关性。方法:选择2016年1月至2019年1月就诊于首都医科大学附属复兴医院神经内科门诊的21例轻度认知障碍(mild cognitive impairment,MCI)患者作为MCI组,同期选择体检中心及门诊的39位认知正常(normal cognition,NC)者作为对照组。所有受试者均进行成套神经心理学量表评估与头颅核磁共振检查。应用自动化海马亚区分割软件FreeSurfer计算各亚区体积,采用听觉词语学习测验(auditory verbal learning test,AVLT)记录序列位置效应结果,观察2组人群亚区体积的差异,并分析其与序列位置效应的相关性。结果:MCI组患者海马各亚区体积均小于对照组,但经多重比较的Bonferroni校正后,仅前下托区差异有统计学意义(P<0.05)。该亚区与AVLT延迟回忆总分及首因分数呈正相关。结论:与对照组相比,MCI患者海马亚区体积减少,其中前下托萎缩更显著,与长时记忆损害相关。

Objective:To explore the correlation between the hippocampal subfields and serial position effect in the elderly with normal cognition and mild cognitive impairment.Methods:A total of 21 subjects with mild cognitive impairment(MCI)treated in Fu Xing Hospital,Capital Medical University from January 2016 to January 2019 were selected as the MCI group,and 39 healthy controls(HC)with normal cognition(NC)from physical examination center and outpatient department were simultaneously selected as control group.All participants completed a set of neuropsychological assessment and were all examined by head MRI.The score of serial position effect was obtained using the auditory verbal learning test(AVLT).T1-weighted structural MRI data were collected after cognitive testing,and the subfields of the hippocampal formation were segmented automatically using the FreeSurfer 6.0 software,then volumetric estimates and estimated total intracranial volume were also calculated.Finally,the relationship between hippocampal subfields and serial position effect were analyzed.Results:The volume of each hippocampal subfield of MCI was smaller than that of the healthy control,but after Bonferroni correction of multiple comparison,only the difference in the presubiculum was statisticallysignificant(P<0.05).The presubiculum was positively correlated with the total score of AVLT delayed recall and the score of primacy effect.Conclusion:Compared with the healthy control,the MCI patients show atrophy in all subfields.The volume of the presubiculum presents the most prominent reduction,which is correlated with the impairment of long-term memory.