Within SEEG shafts, depth separated SOZ pairs, while depth adjustment modestly reduced HFA separation across three cohorts

A pre-registered replication tested whether contact depth separates seizure-onset-zone (SOZ) from non-SOZ bipolar pairs within stereoelectroencephalography (SEEG) shafts, and whether linear depth adjustment removes high-frequency activity (HFA) separation. The analysis reused archived per-pair interictal feature tables from three independent cohorts (85 patients) without new signal processing. Contact 1 was assumed to be deepest. Within-shaft depth AUC was 0.676 (95% CI 0.597–0.752; Holm-adjusted p=0.0001). Linear depth-adjusted HFA AUC was 0.647 (0.600–0.694; p=0.0001), a decrease of 0.060 from unadjusted HFA AUC 0.707 (difference CI −0.106 to −0.012; p=0.017). Across cohorts, depth AUCs were 0.615–0.741 and adjusted HFA AUCs were 0.588–0.699. In the separately reported HUP discovery cohort, the same code gave depth AUC 0.769 and a decrease of 0.158. Thus, the depth finding replicated at a smaller magnitude than in HUP, while most within-shaft HFA separation in the replication cohorts was not explained by a linear depth effect. SOZ labels were deep-biased, so interictal SOZ AUCs should include a depth control. Limits include unverified contact orientation, name-based shaft assignment, clinical labels, short clips, no gray/white-matter control, possible removal of true depth-correlated SOZ signal by adjustment, and different HFA features across cohorts.

stereoelectroencephalography · epilepsy · seizure onset zone · high-frequency activity · depth adjustment · replication · AUC

Admitted 2026-11-09 20:20 UTC1 citing publication

References

usesIn 18 UCLA pediatric SEEG patients, 80–250 Hz bursts and tonic levels both marked clinical seizure-onset channels; neither outperformed the other sci:sha256:2e8119ca326b41f7ea7d9203153c75297ce6512a42fe05ac4177e59632e4f008
Original ds005398 UCLA per-pair features.
usesThe 30–45 Hz aperiodic exponent did not separate seizure-onset channels in 31 SEEG patients sci:sha256:970015c7ad657e77ac8f470146719405ea5536dba9b4dabf2cdf20f1f8c23615
Original HUP ds004100 per-pair features (discovery cohort, reported separately).
usesIn 117 SEEG patients, the top interictal HFA pair was in the clinical SOZ less often than its AUC predicted sci:sha256:6c85dc6f3540bdd41aaeb79a7fbecee27e8b50ac476c990e8241c271ddd4e414
Source of the 4 archived per-pair input tables (SHA-256 values match).
In 32 HUP SEEG patients, SOZ pairs separated within shafts, but contact depth alone matched high-gamma power sci:sha256:6d010dfb61e32199ad36c820136f475e11aff02fb628e65f93e2c6a0d3e2abff
[Legacy relation: reproduces] Pre-registered test of its exploratory depth claims in 3 independent cohorts. The depth AUC replicated (0.68 vs 0.79). The decrease after depth adjustment was smaller (0.06 vs 0.16).
usesSlow-wave–HFA coupling and HFA power distinguish clinical SOZ depth pairs in 43 patients sci:sha256:9f9a03f5ae81593b8a29528c314db6efb6a4c1b7fb63e4d09e778c7b70330fe7
Original ds007118-20 NREM per-pair features.
supportsWithin-shaft SEEG features identified SOZ pairs for three markers but not the aperiodic exponent sci:sha256:501e545e50ce45c3a4bb57d50e0677a21b22b2451450ba9ec930d6b6d4231847
Its within-shaft HFA AUC (no depth control) stays above 0.5 after linear depth adjustment in independent cohorts.
usesAcross 29 SEEG patients, the 30–45 Hz exponent did not separate SOZ channels, while four other features did sci:sha256:115bc8cb0b4c9e536b5f083843a2745508d3c6635a8156b661a9e084f51582a7
Original ds003876 per-pair features.
supportsInterictal power and transient features distinguish SOZ channels after depth matching in 36 SEEG patients, but aperiodic exponent and outcome do not sci:sha256:398ad0c4813dba23a5e3270f2aa74722c599a5916eec0eb90a71accc37c3eed1
Its HUP result that SOZ pairs are near the shaft tip and that depth matching does not remove the feature effect agrees with our depth-matched AUC 0.66 in 3 other cohorts.

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supportsIn 117 patients, contact depth and implant side ranked clinical SOZ pairs near HFA, while HFA retained signal after layout adjustment
It found that SOZ labels are biased toward deep contacts within shafts and that most HFA separation is not a linear depth effect. Over all pairs of the patient (not only within shafts), we also found a depth AUC of 0.64 and an HFA AUC of 0.665 after depth and side adjustment.