Lateralized alpha oscillations are irrelevant for the behavioral retro-cueing benefit in visual working memory

Abstract

The limited capacity of visual working memory (vWM) necessitates the efficient allocation of available resources by prioritizing relevant over irrelevant items. Retro-cues, which inform about the future relevance of items after encoding has already finished, can improve the quality of memory representations of the relevant items. A candidate mechanism of this retro-cueing benefit is lateralization of neural oscillations in the alpha-band, but its precise role is still debated. The relative decrease of alpha power contralateral to the relevant items has been interpreted as supporting inhibition of irrelevant distractors or as supporting maintenance of relevant items. Here, we aimed at resolving this debate by testing how the magnitude of alpha-band lateralization affects behavioral performance: does stronger lateralization improve the precision of the relevant memory or does it reduce the biasing influence of the irrelevant distractor? We found that it does neither: while the data showed a clear retro-cue benefit and a biasing influence of non-target items as well as clear cue-induced alpha-band lateralization, the magnitude of this lateralization was not correlated with any performance parameter. This finding may indicate that alpha-band lateralization, which is typically observed in response to mnemonic cues, indicates an automatic shift of attention that only coincides with, but is not directly involved in mnemonic prioritization.

Dual-task costs in memory recall precision reflect shared representational space.

“…In contrast, there are mixed findings in the literature about the retro-cue effect on recall precision. Whereas some studies suggested that retro-cue may improve the recall precision of the cued items (e.g., Gunseli et al, 2015; Mössing & Busch, 2020; van Moorselaar et al, 2014), other studies did not find retro-cue effect on recall precision (e.g., Kalogeropoulou et al, 2017; Murray et al, 2013; Souza et al, 2014, 2016). If we assume that WM encoding ends once the stimuli disappear, studies reporting retro-cue effects on recall precision would contradict our conclusion that recall precision is unaffected by the competition of attentional resources during WM retention.…”