Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
Max Planck Institute for Psycholinguistics, P.O. Box 310, 6500 AH, Nijmegen, The Netherlands.
Nat Commun. 2020 Apr 14;11(1):1832. doi: 10.1038/s41467-020-15629-7.
Successful working memory performance has been related to oscillatory mechanisms operating in low-frequency ranges. Yet, their mechanistic interaction with the distributed neural activity patterns representing the content of the memorized information remains unclear. Here, we record EEG during a working memory retention interval, while a task-irrelevant, high-intensity visual impulse stimulus is presented to boost the read-out of distributed neural activity related to the content held in working memory. Decoding of this activity with a linear classifier reveals significant modulations of classification accuracy by oscillatory phase in the theta/alpha ranges at the moment of impulse presentation. Additionally, behavioral accuracy is highest at the phases showing maximized decoding accuracy. At those phases, behavioral accuracy is higher in trials with the impulse compared to no-impulse trials. This constitutes the first evidence in humans that working memory information is maximized within limited phase ranges, and that phase-selective, sensory impulse stimulation can improve working memory.
成功的工作记忆表现与在低频范围内运作的振荡机制有关。然而，它们与代表记忆信息内容的分布式神经活动模式的机械相互作用仍然不清楚。在这里，我们在工作记忆保持间隔期间记录 EEG，同时呈现任务无关的高强度视觉脉冲刺激，以增强与工作记忆中保存的内容相关的分布式神经活动的读出。使用线性分类器对该活动进行解码，发现在脉冲呈现时刻，θ/α 范围内的振荡相位对分类准确性有显著的调制。此外，在表现出最大解码准确性的相位，行为准确性最高。在这些相位，与无脉冲试验相比，在有脉冲的试验中行为准确性更高。这是人类中首次证明工作记忆信息在有限的相位范围内最大化，并且相位选择性的感觉脉冲刺激可以改善工作记忆。
