Synergistic prioritization in memory: Electrophysiological evidence for metamemory-driven automatic and strategic mechanisms

Abstract

Adaptively prioritizing high-value information is crucial for maximizing memory efficiency. Although recent research has demonstrated that prioritization in value-directed remembering relies on automatic and strategic mechanisms, it is controversial whether these mechanisms operate independently or synergistically to enhance memory selectivity. In particular, the neural correlations of how the underlying metamemory regulates these processes remain unclear. Thirty healthy adults completed an adapted value-directed remembering paradigm in which metamemory was manipulated through pre-encoding cues indicating the upcoming test form (recognition/free recall/unknown). During the encoding phase, participants studied high- and low-value words, and event-related potentials (ERPs) and time-frequency activity were recorded to examine the roles of automatic and strategic mechanisms, which was followed by a cued recall test. The results revealed that metamemory modulated resource allocation via N400 and frontal slow wave amplitudes and strategic selection through alpha- and theta-band time-frequency activity, collectively influencing the strategic mechanism. Specifically, time-frequency activity in the theta band related to the suppression of low-value items was more strongly correlated with memory selectivity than was time-frequency activity in the alpha band related to the selection of high-value items. The automatic mechanism indexed by the P2 amplitude is dynamically adapted to engage with the strategic mechanism. These findings provide the first neurophysiological evidence for metamemory-driven synergy between automatic and strategic mechanisms, validating responsible remembering theory. Crucially, our results challenge the traditional view of selective enhancement as dominant, instead highlighting the critical role of inhibition in priority encoding.