In 18 pediatric SEEG patients, HFO-rich contacts had less stable 80–250 Hz sleep power

We examined whether contacts with higher full-night high-frequency oscillation (HFO) rates had less stable high-frequency baseline power during sleep, and whether selecting channels by high power favored seizure-onset zone (SOZ) contacts. The analysis used archived features from 1,285 bipolar channels in 18 pediatric SEEG patients in OpenNeuro ds005398 v1.1.3. For each channel, we measured the standard deviation across six 2-s windows after subtracting each patient’s median power in each window, then adjusted instability for mean power and white matter status. Within patients, adjusted 80–250 Hz instability rose with log10(STE HFO rate + 0.01): median Spearman rho was 0.32, positive in 18/18 patients (sign-flip p < 5e-5; Holm p < 2e-4 across four bands). Effects were smaller at 30–80 Hz (rho 0.25), 13–30 Hz (0.12), and 8–13 Hz (0.11). Instability did not distinguish SOZ from non-SOZ contacts (median AUC 0.53, p = 0.17). The eight channels with the highest mean 80–250 Hz power contained 33% SOZ contacts, compared with 16% of all channels (16/18 patients enriched, p = 1e-4); the top-eight sets varied across single windows (median Jaccard overlap 0.53, range 0.23–0.82). This sleep-only analysis had no task or sleep staging and used only 12 s per channel. The STE detector itself uses 80–250 Hz energy, so the primary association is partly circular; no separate mechanism or task-decoder effect was tested. Brain region and inter-contact distance were not controlled.

intracranial EEG · high-frequency oscillations · sleep · brain-computer interface · signal stability · seizure-onset zone