School of Psychology, University of Roehampton, London, UK.
Neuropsychology Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy.
Sci Rep. 2024 Feb 28;14(1):4879. doi: 10.1038/s41598-024-53507-0.
Episodic memory shows the largest degree of age-related decline. Anodal transcranial Direct Current Stimulation (tDCS) can enhance episodic memory in aging but there is also evidence of response variability even when using identical stimulation parameters. To explore which inter-individual factors (i.e. age, education, encoding performance, cognitive reserve, tDCS group and timing of tDCS application) may directly and/or indirectly modulate verbal memory recall, we used data from our previous tDCS studies that showed enhanced episodic memory recall in 80 healthy older adults. In these studies we used the same paradigm and stimulation parameters but tDCS was applied during different memory stages. Memory recall was tested 48 hours and 30 days after encoding. Univariate regression models showed that tDCS group (Anodal vs. Sham) predicted memory recall, indicating higher scores in the Anodal group than in the Sham group. Encoding performance predicted memory recall in both tDCS groups. Multiple regression models revealed that cognitive reserve, measured with a life experience questionnaire, predicted memory recall only for the Anodal group. Higher cognitive reserve was linked to better memory recall. Accounting for individual differences in cognitive reserve at baseline helps to explain tDCS responsiveness. This knowledge may contribute to optimize its use in older adults.
情景记忆表现出最大程度的与年龄相关的下降。阳极经颅直流电刺激（tDCS）可以增强衰老过程中的情景记忆，但即使使用相同的刺激参数，也有证据表明存在反应变异性。为了探索哪些个体间因素（即年龄、教育、编码表现、认知储备、tDCS 组和 tDCS 应用的时间）可能直接和/或间接地调节言语记忆回忆，我们使用了来自我们之前的 tDCS 研究的数据，这些研究表明在 80 名健康老年人中增强了情景记忆回忆。在这些研究中，我们使用了相同的范式和刺激参数，但 tDCS 在不同的记忆阶段应用。记忆回忆在编码后 48 小时和 30 天进行测试。单变量回归模型显示，tDCS 组（阳极 vs. 假刺激）预测了记忆回忆，表明阳极组的分数高于假刺激组。编码表现预测了 tDCS 组的记忆回忆。多元回归模型表明，认知储备，用生活经历问卷测量，仅预测了阳极组的记忆回忆。更高的认知储备与更好的记忆回忆有关。在基线时考虑认知储备的个体差异有助于解释 tDCS 的反应性。这些知识可能有助于优化其在老年人中的应用。
