Visual working memory (VWM) allows storing goal-relevant information to guide future behavior. Prior work suggests that VWM is spatially organized and relies on spatial attention directed toward locations at which memory items were encoded, even if location is task-irrelevant. Importantly, attention often needs to be dynamically redistributed between locations, for example, in preparation for an upcoming probe. Very little is known about how attentional resources are distributed between multiple locations during a VWM task and even less about the dynamic changes governing such attentional shifts over time. This is largely due to the inability to use behavioral outcomes to reveal fast dynamic changes within trials. We here demonstrated that EEG steady-state visual evoked potentials (SSVEPs) successfully track the dynamic allocation of spatial attention during a VWM task. Participants were presented with to-be-memorized gratings and distractors at two distinct locations, tagged with flickering discs. This allowed us to dynamically track attention allocated to memory and distractor items via their coupling with space by quantifying the amplitude and coherence of SSVEP responses in the EEG signal to flickering stimuli at the former memory and distractor locations. SSVEP responses did not differ between memory and distractor locations during early maintenance. However, shortly before probe comparison, we observed a decrease in SSVEP coherence over distractor locations indicative of a reallocation of spatial attentional resources. RTs were shorter when preceded by stronger decreases in SSVEP coherence at distractor locations, likely reflecting attentional shifts from the distractor to the probe or memory location. We demonstrate that SSVEPs can inform about dynamic processes in VWM, even if location does not have to be reported by participants. This finding not only supports the notion of a spatially organized VWM but also reveals that SSVEPs betray a dynamic prioritization process of working memory items and locations over time that is directly predictive of memory performance.

视觉工作记忆（VWM）允许存储与目标相关的信息以指导未来的行为。先前的研究表明，VWM 是空间组织的，并且依赖于针对记忆项编码位置的空间注意力，即使位置与任务无关。重要的是，注意力通常需要在不同位置之间动态地重新分配，例如，为即将到来的探测做准备。人们对 VWM 任务期间注意力资源如何在多个位置之间分配知之甚少，更不了解随着时间的推移控制这种注意力转移的动态变化。这主要是由于无法使用行为结果来揭示试验中的快速动态变化。我们在这里证明了 EEG 稳态视觉诱发电位 (SSVEP) 成功跟踪 VWM 任务期间空间注意力的动态分配。参与者在两个不同的位置看到了需要记忆的光栅和干扰物，并用闪烁的圆盘标记。这使得我们能够通过量化脑电图信号中 SSVEP 响应对先前记忆和干扰项位置上的闪烁刺激的幅度和连贯性，通过记忆和干扰项与空间的耦合来动态跟踪分配给记忆和干扰项的注意力。在早期维护期间，记忆位置和干扰位置之间的 SSVEP 反应没有差异。然而，在探针比较之前不久，我们观察到干扰位置上的 SSVEP 一致性下降，表明空间注意力资源的重新分配。当干扰物位置处的 SSVEP 一致性下降更强烈时，RT 会更短，这可能反映了注意力从干扰物转移到探测或记忆位置。我们证明，SSVEP 可以告知 VWM 中的动态过程，即使参与者不必报告位置。这一发现不仅支持了空间组织 VWM 的概念，而且还揭示了 SSVEP 背叛了工作记忆项目和位置随时间变化的动态优先级过程，可直接预测记忆性能。