Data_Sheet_1_Older adults with lower working memory capacity benefit from transcranial direct current stimulation when combined with working memory training: A preliminary study.docx

Aging is a very diverse process: successful agers retain most cognitive functioning, while others experience mild to severe cognitive decline. This decline may eventually negatively impact one’s everyday activities. Therefore, scientists must develop approaches to counteract or, at least, slow down the negative change in cognitive performance of aging individuals. Combining cognitive training and transcranial direct current stimulation (tDCS) is a promising approach that capitalizes on the plasticity of brain networks. However, the efficacy of combined methods depends on individual characteristics, such as the cognitive and emotional state of the individual entering the training program. In this report, we explored the effectiveness of working memory training, combined with tDCS to the right dorsolateral prefrontal cortex (DLPFC), to manipulate working memory performance in older individuals. We hypothesized that individuals with lower working memory capacity would benefit the most from the combined regimen. Thirty older adults took part in a 5-day combined regimen. Before and after the training, we evaluated participants’ working memory performance with five working memory tasks. We found that individual characteristics influenced the outcome of combined cognitive training and tDCS regimens, with the intervention selectively benefiting old-old adults with lower working memory capacity. Future work should consider developing individualized treatments by considering individual differences in cognitive profiles.

衰老是一个高度多样化的过程：成功衰老的群体可保留大部分认知功能，而其余人群则会经历轻度至重度的认知衰退。这种衰退最终可能对个体的日常活动产生负面影响。因此，科研人员亟需开发能够抵消、至少延缓衰老个体认知表现负面变化的方法。将认知训练与经颅直流电刺激（transcranial direct current stimulation, tDCS）相结合是一种颇具前景的方案，其依托于脑网络的可塑性。然而，联合干预的效果取决于个体特征，例如参与训练项目的个体的认知与情绪状态。在本报告中，我们探究了工作记忆训练结合右侧背外侧前额叶皮层（right dorsolateral prefrontal cortex, DLPFC）经颅直流电刺激对老年群体工作记忆表现的调控效果。我们提出假设：工作记忆容量较低的个体将从该联合方案中获益最多。30名老年成年人参与了为期5天的联合干预方案。在训练前后，我们通过五项工作记忆任务评估了参与者的工作记忆表现。研究结果显示，个体特征会对认知训练与tDCS联合干预的效果产生影响，该干预仅对工作记忆容量较低的高龄老年群体具有选择性获益效果。未来的研究应考虑结合个体认知特征的差异，开发个性化的治疗方案。