Integrity of white matter structure is related to episodic memory performance in the low-educated elderly

ABSTRACT The low-educated elderly are a vulnerable population in whom studying the role of white matter integrity on memory may provide insights for understanding how memory declines with aging and disease. Methods: Thirty-one participants (22 women), 23 cognitively healthy and eight with cognitive impairment-no dementia, aged 80.4 ± 3.8 years, with 2.2 ± 1.9 years of education, underwent an MRI scan with diffusion tensor imaging (DTI) acquisition. We verified if there were correlations between the performance on the Brief Cognitive Screening Battery (BCSB) and the Rey Auditory Verbal Learning Test (RAVLT) with DTI parameters. Results: The BCSB delayed recall task correlated with frontotemporoparietal connection bundles, with the hippocampal part of the cingulum bilaterally and with the right superior longitudinal fasciculus. The RAVLT learning and delayed recall scores also correlated with the hippocampal part of the cingulum bilaterally. Conclusions: Although preliminary, our study suggests that the integrity of white matter frontotemporoparietal fasciculi seems to play a role in episodic memory performance in the low-educated elderly. This finding opens opportunities to study potential targets for memory decline prevention in vulnerable populations.

摘要：低教育水平老年人属于脆弱人群，探究脑白质完整性对记忆的作用机制，或可为理解衰老与疾病相关的记忆衰退提供新视角。
方法：本研究共纳入31名受试者（22名女性），其中23名认知健康、8名存在认知损害但未达到痴呆诊断标准，受试者年龄为80.4±3.8岁，受教育年限为2.2±1.9年；所有受试者均接受了包含弥散张量成像（diffusion tensor imaging, DTI）序列的磁共振成像（magnetic resonance imaging, MRI）扫描。本研究验证了简易认知筛查量表（Brief Cognitive Screening Battery, BCSB）与雷伊听觉语言学习测试（Rey Auditory Verbal Learning Test, RAVLT）的得分与DTI参数之间是否存在相关性。
结果：BCSB延迟回忆任务得分与额颞顶连接束、双侧扣带回海马部以及右侧上纵束存在显著相关性。RAVLT学习得分与延迟回忆得分同样与双侧扣带回海马部存在显著相关性。
结论：尽管本研究属于初步探索性工作，但结果提示，低教育水平老年人的额颞顶白质束完整性似乎对情景记忆表现具有影响。该研究发现为脆弱人群记忆衰退的潜在预防靶点研究提供了新的方向。