Mechanisms of Working Memory Prioritization: Retro-Cues vs. Saccadic Preparation.

Abstract

Selective internal attention allows working memory (WM) contents to be prioritized according to task demands, a process typically investigated with the retro-cue paradigm. In this paradigm, a cue presented during WM maintenance indicates which item will be tested, enabling memory-based prioritization of task-relevant and typically enhancing memory performance. Recent findings suggest, however, that saccade preparation toward the location of a WM item can also produce prioritization linked to oculomotor selection. In the present study, we compared behavioral performance and neural oscillatory dynamics associated with action-oriented prioritization induced by saccade preparation and memory-based prioritization elicited by spatial and color retro-cues. Behaviorally, saccade-based prioritization produced only a modest benefit relative to incongruent items, whereas both types of retro-cues yielded substantially larger improvements. At the neural level, alpha-band lateralization showed a similar spatial-attention pattern across all prioritization conditions, supporting a shared covert attentional mechanism. In contrast, bilateral posterior alpha power was reduced following retro-cues compared to saccadic preparation, consistent with a release of WM load when non-cued items are deprioritized. Overall, our results suggest that these forms of prioritization may rely on overlapping spatial-attention processes, but differ in strategic control and their consequences for load management. Importantly, retro-cue-based prioritization produces a stronger behavioral enhancement than prioritization associated with saccade preparation.