Across 3 SEEG cohorts, HFA increased with SOZ-contact count, but one-contact pair rankings differed by cohort

In archived per-pair feature tables from 104 patients in three public SEEG cohorts (HUP ds004100, n=32; ds003876, n=29; and NREM ds007118–20, n=43), interictal high-frequency activity (HFA) increased with the number of clinically labeled seizure-onset-zone (SOZ) contacts in a bipolar pair. Across patients, HFA ranked higher for two-contact than one-contact pairs (mean AUC 0.68, 95% CI 0.61–0.75; n=86; Holm-adjusted p=1×10⁻⁴) and for one-contact than zero-contact pairs (AUC 0.64, 95% CI 0.58–0.68; n=99; Holm-adjusted p=1×10⁻⁴). Thus, labeling a pair as SOZ when either contact is SOZ combines groups with different HFA, and the strict two-contact versus zero-contact SOZ AUC was 0.043 higher than the lenient AUC in the paired comparison. Cohorts differed: one-contact pairs were near zero-contact pairs in HUP (AUC 0.54) and near two-contact pairs in ds003876 (AUC 0.51). Spike rate did not distinguish two- from one-contact pairs (AUC 0.53). Labels were clinical and had no surgical-outcome validation; contact count also reflects distance to the labeled SOZ edge. Clips were short (90–120 s), feature pipelines differed between cohorts, and tissue type was not controlled. No new signal processing was performed.

stereo-EEG · epilepsy · seizure onset zone · high-frequency activity · bipolar pairs · interictal · AUC · labeling