Zhu Rongjuan, Luo Yangmei, Wang Ziyu, You Xuqun
Key Laboratory for Behavior and Cognitive Neuroscience of Shaanxi Province, School of Psychology, Shaanxi Normal University, Xi'an, China.
Cogn Neurosci. 2022 Jan;13(1):26-37. doi: 10.1080/17588928.2021.1877648. Epub 2021 Mar 19.
Spatial working memory (SWM) is an essential cognitive ability that supports complex tasks, but its capacity is limited. Studies using transcranial direct current stimulation (tDCS) have shown potential benefits for SWM performance. Recent studies have shown that repeated short applications of tDCS affected corticospinal excitability. Moreover, neuroimaging studies have indicated that the pattern of neural activity measured in the posterior parietal cortex (PPC) tracks SWM ability. It is unknown whether repeated tDCS can enhance SWM and whether varied tDCS protocols (single 10 min tDCS, 10 min tDCS-5 min break-10 min tDCS, 10 min tDCS-20 min break-10 min tDCS) over the right PPC have different effects on SWM. The current study investigated whether offline single-session and repeated tDCS over the right PPC affects SWM updating, as measured by spatial 2-back and 3-back tasks. The results showed that stimulating the right PPC with repeated 10 min anodal tDCS significantly improved the response speed of the spatial 2-back task relative to single-session tDCS. Repeated 10 min tDCS with a longer interval (i.e. inter-stimulation interval of 20 min) enhanced the response speed of the spatial 3-back task. Altogether these findings provide causal evidence that suggests that the right PPC plays an important role in SWM. Furthermore, repeated tDCS with longer intervals may be a promising intervention for improving SWM-related function.
空间工作记忆（SWM）是一种支持复杂任务的重要认知能力，但其容量有限。使用经颅直流电刺激（tDCS）的研究表明，其对SWM表现具有潜在益处。最近的研究表明，重复短时间应用tDCS会影响皮质脊髓兴奋性。此外，神经影像学研究表明，在后顶叶皮层（PPC）测量的神经活动模式可追踪SWM能力。尚不清楚重复tDCS是否能增强SWM，以及针对右侧PPC的不同tDCS方案（单次10分钟tDCS、10分钟tDCS-5分钟休息-10分钟tDCS、10分钟tDCS-20分钟休息-10分钟tDCS）对SWM是否有不同影响。本研究调查了右侧PPC的离线单节次和重复tDCS是否会影响通过空间2-back和3-back任务测量的SWM更新。结果表明，相对于单节次tDCS，重复10分钟阳极tDCS刺激右侧PPC可显著提高空间2-back任务的反应速度。间隔较长（即刺激间隔为20分钟）的重复10分钟tDCS可提高空间3-back任务的反应速度。总之，这些发现提供了因果证据，表明右侧PPC在SWM中起重要作用。此外，间隔较长的重复tDCS可能是改善与SWM相关功能的一种有前景的干预措施。
