Résumé
Magnetophosphenes are visual percepts induced by head exposure to extremely low-frequency magnetic fields, but their neural correlates remain unclear. Here, we recorded EEG in 13 participants during 20 Hz transcranial alternating magnetic stimulation (tAMS, delivered at 0, 5, 50 mT) and analyzed spectral and nonlinear dynamics. Perception occurred almost exclusively at 50 mT. This condition was associated with distributed broadband gamma increases, without a focal occipital marker. Crucially, gamma enhancement co-occurred with reduced sample entropy, indicating more regular and structured brain dynamics. Overall, these findings support a distributed, state-dependent neural signature rather than a classical occipital sensory response.