Comparing retro-cue benefit mechanisms in visual working memory: Completely valid vs. highly valid retro-cues

Abstract

Abstract Visual working memory (VWM) plays a crucial role in temporarily maintaining and manipulating visual information. Retro-cue benefit (RCB) refers to enhancement in memory performance when attention is directed toward a subset of items within VWM after their initial encoding. Our recent EEG studies have indicated that cue validity can influence the mechanisms underlying RCB formation, but previous research has not investigated whether differences exist in the RCB formation mechanisms between completely valid and highly valid cue conditions. This study aims to examine the consistency of RCB mechanisms when retro-cues are completely valid (100% cue validity), compared with highly valid (80% cue validity). We manipulated retro-cue validity in our experiments and examined cognitive processing mechanisms under different cue validity conditions using EEG technology. We focused on the N2pc component, reflecting attentional resource allocation, and the contralateral delay activity (CDA) component, reflecting quantity of information retained in VWM. The results, encompassing both behavioral and event-related potential (ERP) findings, demonstrate that participants in both the 100% and 80% cue validity conditions exhibit robust RCB. Notably, the degree of RCB remains consistent between these conditions, indicating that participants utilize retro-cues to enhance VWM performance to the same extent. In the 80% cue validity condition, a significant retro-cue cost (RCC) is observed, suggesting that participants selectively eliminate uncued items from VWM. In invalid trials of this condition, response accuracy drops to chance levels, supporting the removal hypothesis. ERP results reveal that attentional resource allocation patterns (N2pc) and the quantity of information retained in VWM (CDA) remain uniform across cue validity conditions. The mechanism responsible for RCB formation appears to involve an all-or-nothing process of discarding uncued information rather than a flexible resource allocation strategy. This study provides insights into the attention allocation and information-processing mechanisms in VWM, suggesting that conclusions drawn from tasks with completely valid retro-cues can be integrated with findings from highly valid cue tasks. These findings also shed light on internal attentional resource allocation flexibility during RCB formation, as well as contribute to our understanding of attention processes in VWM.