EEG recording during visual aura in migraine: Results by quantitative analysis

Migraine with aura is characterized by transient neurological symptoms, most commonly visual, lasting 5–60 min and usually preceding headache (IHS, 2018). The gradual spread of aura symptoms is clinically linked to cortical spreading depolarization (CSD), a propagating wave of neuronal hyperactivity followed by hypoactivity travelling postero-anteriorly at speed of 3 mm/min (Charles and Baca, 2013). Electroencephalography (EEG) studies have associated CSD with cortical voltage suppression, particularly at higher frequencies; however, due to the difficulty of recording EEG during aura, evidence largely derives from patients with ischemic stroke, subarachnoid hemorrhage (SAH), or severe brain injury, in whom CSDs are frequent (Puchala et al., 2025). The literature includes only one recent Stereo-Electroencephalography (sEEG) study of one patient, capturing an entire visual migraine aura, showing unilateral CSD contralateral to aura symptoms, but affected by epilepsy which could limiting robustness result (McLeod et al., 2025). Three additional quantitative scalp EEG studies exist, but none covered or specified the full aura or performed a multi-epoch analysis, both strengths of our study (Schoenen et al., 1987, Seri et al., 1993, Riederer et al., 2024).