Work

EEG biomarkers of cognitive load: Insights from incremental element encoding in short-term working memory

Year: 2025

Type: article

Abstract: Cognitive load reflects the mental effort required to process, maintain, and manipulate information. Traditional methods for assessing cognitive load often rely on subjective measures or static task designs, limiting their ability to monitor rapid fluctuations in real time. In this study, we explore an electroencefalography-based framework for tracking cognitive load during incremental element encoding, where information is progressively added to short-term working memory. This approach simulates real-world scenarios, where cognitive demands change dynamically. By analyzing EEG spectral absolute power across theta (4–8 Hz), alpha (8–13 Hz), low beta (13–20 Hz), high beta (20–30 Hz), and gamma (>30 Hz) bands, we identified novel biomarkers of cognitive load. Frontal low beta desynchronization emerged as a reliable biomarker, increasing as more elements were encoded. Moreover, beta power shifted to higher frequencies with increasing cognitive load in both frontal and parietal regions, reflecting neural adjustments to more complex demands. Theta and alpha power increased relative to the resting state in the aforementioned regions, but remained stable during encoding, reflecting general task engagement rather than encoding complexity. These findings provide novel insights into cognitive load monitoring, potentially enabling more precise and efficient real-time estimation.

Source: Biomedical Signal Processing and Control

DOI: 10.1016/j.bspc.2025.108511