Transcranial direct current stimulation (tDCS) on the dorsolateral prefrontal cortex (DLPFC) was used to improve foreign-langue learning while using mental imagery. Participants underwent two sessions of 1 mA, 1.5 mA, or sham stimulation prior to learning Swahili-English word pairs two consecutive days. During learning, participants were encouraged to create a mental image of the associated English word. Twenty-four hours after learning and one week later, participants received a cued recall test. A linear dose–response effect of stimulation was found across both tests that occurred long after the immediate effects of stimulation. Follow-up comparisons revealed that only the 1.5 mA condition differed from the sham group. Exploratory moderating effects revealed interactions with sleep quality and handedness. Those with poorer sleep and who were left-handed showed greater recall after 1.5 mA of stimulation than those with better sleep and right-handers. A follow-up behavioral study probing strategy usage indicated that mental imagery strategy use did not strongly impact learning but point to other possible mechanisms including the importance of attending to multimodal perceptual details and memory consolidation. This preliminary evidence supports the role of the DLPFC or connected regions in foreign language vocabulary learning and verbal memory encoding.

背外侧前额叶皮层 (DLPFC) 上的经颅直流电刺激 (tDCS) 用于在使用心理意象的同时改善外语学习。在连续两天学习斯瓦希里语-英语单词对之前，参与者经历了两次 1 mA、1.5 mA 或假刺激。在学习过程中，鼓励参与者创建相关英语单词的心理形象。学习后 24 小时和一周后，参与者接受了提示回忆测试。在刺激的即时效应发生很久之后的两个测试中都发现了刺激的线性剂量反应效应。后续比较显示，只有 1.5 mA 条件与假手术组不同。探索性调节效应揭示了睡眠质量和惯用手的相互作用。那些睡眠较差和惯用左手的人在 1.5 mA 的刺激后表现出比睡眠较好和惯用右手的人更好的回忆。一项探索策略使用的后续行为研究表明，心理意象策略的使用并未对学习产生强烈影响，但指出了其他可能的机制，包括注意多模态感知细节和记忆巩固的重要性。这一初步证据支持 DLPFC 或连接区域在外语词汇学习和语言记忆编码中的作用。一项探索策略使用的后续行为研究表明，心理意象策略的使用并未对学习产生强烈影响，但指出了其他可能的机制，包括注意多模态感知细节和记忆巩固的重要性。这一初步证据支持 DLPFC 或连接区域在外语词汇学习和语言记忆编码中的作用。一项探索策略使用的后续行为研究表明，心理意象策略的使用并未对学习产生强烈影响，但指出了其他可能的机制，包括注意多模态感知细节和记忆巩固的重要性。这一初步证据支持 DLPFC 或连接区域在外语词汇学习和语言记忆编码中的作用。