Zheng Zhiwei, Li Rui, Xiao Fengqiu, He Rongqiao, Zhang Shouzi, Li Juan
Center on Aging Psychology, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.
Psych J. 2018 Jun;7(2):77-91. doi: 10.1002/pchj.212. Epub 2018 Apr 19.
Older adults demonstrate notable individual differences in associative memory. Here, resting-state functional magnetic resonance imaging (rsfMRI) was used to investigate whether intrinsic brain activity at rest could predict individual differences in associative memory among cognitively healthy older adults. Regional amplitude of low-frequency fluctuations (ALFF) analysis and a correlation-based resting-state functional connectivity (RSFC) approach were used to analyze data acquired from 102 cognitively normal elderly who completed the paired-associative learning test (PALT) and underwent fMRI scans. Participants were divided into two groups based on the retrospective self-reports on whether or not they utilized encoding strategies during the PALT. The behavioral results revealed better associative memory performance in the participants who reported utilizing memory strategies compared with participants who reported not doing so. The fMRI results showed that higher associative memory performance was associated with greater functional connectivity between the right superior frontal gyrus and the right posterior cerebellum lobe in the strategy group. The regional ALFF values in the right superior frontal gyrus were linked to associative memory performance in the no-strategy group. These findings suggest that the regional spontaneous fluctuations and functional connectivity during rest may subserve the individual differences in the associative memory in older adults, and that this is modulated by self-initiated memory strategy use.
老年人在联想记忆方面表现出显著的个体差异。在此，静息态功能磁共振成像（rsfMRI）被用于研究静息状态下的大脑内在活动是否能够预测认知健康的老年人在联想记忆方面的个体差异。采用低频振幅（ALFF）分析和基于相关性的静息态功能连接（RSFC）方法，对102名认知正常的老年人的数据进行分析，这些老年人完成了配对联想学习测试（PALT）并接受了功能磁共振成像扫描。根据参与者在PALT期间是否使用编码策略的回顾性自我报告，将他们分为两组。行为结果显示，与未报告使用记忆策略的参与者相比，报告使用记忆策略的参与者在联想记忆表现上更好。功能磁共振成像结果表明，在策略组中，较高的联想记忆表现与右侧额上回和右侧小脑后叶之间更强的功能连接有关。在无策略组中，右侧额上回的区域ALFF值与联想记忆表现相关。这些发现表明，静息状态下的区域自发波动和功能连接可能有助于老年人联想记忆的个体差异，并且这受到自我启动的记忆策略使用的调节。
