Résumé
The definition of threshold effects for extremely low-frequency magnetic fields (ELF-MF) is essential for establishing exposure guidelines. Current standards are largely based on the perception of magnetophosphenes, a retinal phenomenon induced by time-varying magnetic fields. However, the effects of ELF-MF on higher-level brain functions remain insufficiently documented. The present study aims to investigate the effects of a 50 Hz sinusoidal magnetic field on working memory performance and associated EEG activity in healthy participants. Working memory was assessed using a 3-back task performed before, during, and after magnetic field exposure. A whole-head exposure system based on Helmholtz-like coils was used to deliver 11 flux density conditions (0–100 mT) in randomized order, with sham-controlled sessions. Behavioral measures included accuracy and reaction time. EEG was recorded using a 64-channel system and analyzed using complementary approaches. Spectral analyses and functional connectivity were combined with nonlinear methods, including sample entropy and recurrence quantification analysis (RQA), to characterize the temporal dynamics and complexity of brain activity. This study is designed to evaluate whether ELF-MF exposure is associated with measurable changes in cognitive performance and EEG markers. By combining behavioral and electrophysiological measures, it contributes to improving our understanding of the interactions between magnetic fields and brain function, and may help refine current approaches used to assess ELF-MF effects on the central nervous system.