Resting-state EEG gamma power predicts immediate and delayed recall in healthy adults

Abstract

Objective: Resting-state EEG (rsEEG) provides insights into neural mechanisms underlying memory by reflecting intrinsic brain activity. This study tested whether rsEEG spectral power and theta-gamma phase-amplitude coupling (PAC) can predict memory performance in healthy adults. Methods: Twenty-four healthy adults participated in two rsEEG recording sessions, followed by memory tests assessing multimodal Working Memory (WM), Immediate Recall (IR), and Delayed Recall (DR). The predictive value of rsEEG spectral power across frequency bands and theta-gamma PAC was analyzed in relation to memory performance. Results: High-gamma (h-γ, 51–100 Hz) power significantly predicted IR and DR, accounting for over 43% of the variance. Temporal and frontal h-γ power positively correlated with memory performance, while posterior h-γ power showed a negative correlation. Temporal low-gamma (30–49 Hz) power positively predicted DR, and posterior and frontal theta power was significantly linked to IR. Other frequency bands showed marginal associations, and theta-gamma PAC had limited predictive value. Conclusions: Spontaneous gamma activity emerged as a key predictor of memory performance in healthy adults, highlighting the role of brain networks in encoding and retrieval processes.