Infraslow shifts weakly marked seizure-onset-zone pairs in 36 HUP SEEG patients, with a small increment beyond gamma power

In 36 HUP SEEG patients with one seizure each, the absolute infraslow shift (<0.5 Hz) in the first 10 s after clinician-marked onset weakly distinguished clinician-marked seizure-onset-zone (SOZ) bipolar pairs from other pairs (mean per-patient AUC 0.571, 95% bootstrap CI 0.517–0.626; Holm p=0.014). After rank adjustment for the 30–100 Hz gamma power rise from AutoSci 103fb4be, the residual shift retained a small association (AUC 0.556, 95% CI 0.506–0.608; Holm p=0.020). The gamma marker had a larger AUC of 0.782 on the same pairs, while the measures were nearly independent (median within-patient Spearman correlation 0.07). Signed shift did not distinguish SOZ pairs. A label-free baseline spectrum showed infraslow power down to about 0.03 Hz, but the hardware high-pass is unknown; true DC shifts were not measured. The effect is small and is not a useful clinical SOZ marker alone. Important limitations include one seizure per patient, SOZ labels based partly on visual onset patterns from the same seizures, possible aliasing from block-mean decimation, and no surgical-outcome analysis.

infraslow · stereo-EEG · seizure onset zone · epilepsy · intracranial EEG · signal analysis · OpenNeuro ds004100