老年人情绪记忆相关脑结构改变基于体素形态学测量研究

The brain structures related to emotional memory in the elderly: a voxel-based morphometry study

目的采用基于体素形态学测量(VBM)和行为学相结合的方法,检测老年人全脑容积及情绪记忆成绩,以探讨老年人情绪记忆增强效应相关脑区形态学特点。方法 47名健康老年人参加实验。实验过程包括情绪记忆行为学检测和MRI两个阶段,其中行为学检测包括记忆编码和再认,并记录行为学成绩。利用3.0T MRI采集全脑容积数据。采用VBM5对3D MRI数据进行分割处理,获得全脑灰质、脑白质和脑脊液容积数据。运用SPM5和SPSS13.0统计软件包进行相关统计分析。结果老年人对情绪图片再认正确率较中性图片正确率高(t=2.08,P=0.04),两种图片的反应正确率与年龄呈显著负相关(中性r:=0.58,P=0.00;情绪r:=0.30,P=0.04),但情绪记忆增强效应与年龄呈显著正相关(r=0.37,P=0.01),情绪记忆增强效应主要相关脑区包括左侧前额叶背外侧及右侧枕叶。结论老年人行为学成绩随年龄增长逐渐下降,但情绪记忆增强效应仍然存在,并从脑形态结构水平证实了前额叶背外侧和枕叶脑区保持情绪记忆增强效应的重要脑区,从而进一步扩展了功能成像的相关研究结果。

Objective To explore morphological characters of brain regions related to the enhancement effect of emotional memory,brain volume of old adult and behavioral performance of emotional memory were measured,combining voxel-based morphometry（VBM） and behavior.Methods 47 healthy elderly samples,the experimental processes included MRI and behavioral performance of emotional memory which have two phases,encoding and retrieval phase.Behavioral performance was recorded and whole-brain 3D MRI data were acquired via 3.0T MRI.3D MRI data were segmented by VBM5 and whole-brain volume of gray matter,white matter and CSF were produced.SPM5 and SPSS13.0 were used for statistical analysis of 3D MRI data and behavioral data,respectively.Results In old adult,retrieval accuracy of emotional pictures were higher than that of neutral pictures（t=2.08,P=0.04）.Retrieval accuracy of the two pictures has a significant negative correlation with age（neutral： r=0.58,P=0.00;emotion： r=0.30,P=0.04）,but the emotional memory enhancement effect is a significant positive correlation with age（r=0.37,P=0.01）.Brain regions related to emotion enhancement effect included left dorsal-lateral prefrontal lobe and right occipital lobe.Conclusion This study confirms that old people behavior scores gradually decline with aging,but emotional memory enhancement effect remained,and from brain morphology level we confirmed the dorsal-lateral prefrontal and occipital lobe brain regions are the important brain structure keeping enhanced effect of emotional memory,thus further expanded related functional imaging studies results.