In 32 HUP patients, matched SEEG edges showed lower 1–40 Hz SOZ coupling; high-gamma envelope coupling did not differ

We tested whether interictal seizure-onset-zone (SOZ)-to-non-SOZ edges have lower coupling than non-SOZ-to-non-SOZ edges after controlling for electrode shaft pair and edge length. We analyzed an archived edge table from 32 patients in the HUP iEEG dataset (OpenNeuro ds004100, version 1.1.3): 200,751 inter-shaft edges from 70 seconds of awake interictal SEEG per patient, with clinical SOZ labels and fsaverage coordinates. The pre-registered primary analysis compared each SOZ-to-non-SOZ edge with non-SOZ edges on the same shaft pair within 5 mm in length. Matched 1–40 Hz absolute correlation was lower by 0.0075 (95% CI −0.0124 to −0.0031; 10/32 patient means positive; Holm-adjusted p=0.005), about 11% of the mean non-SOZ coupling (0.070). The 65–115 Hz Hilbert-envelope measure showed no SOZ-to-non-SOZ deficit (−0.0006, 95% CI −0.0077 to +0.0070; Holm p=0.87). Within shaft pairs, SOZ-to-non-SOZ edges were 3.93 mm shorter; matching length changed the low-frequency estimate from −0.0091 to −0.0075. Sensitivity analyses retained the low-frequency deficit after excluding HUP173 (p=0.0048) and with a 2.5 mm matching window (p=0.0031). Unmatched edges showed no difference (low-frequency +0.0011, p=0.69), consistent with shaft-pair composition hiding the deficit. High-gamma ss edges were stronger than sn edges (+0.0356, p=0.0008), consistent with SOZ-internal coupling rather than isolation. Limitations include clinical rather than outcome-based SOZ labels, one dataset, short awake recordings, fsaverage coordinates, bipolar reference, zero-lag measures, and a small effect; the near-edge stratum had a wide confidence interval.

seizure-onset zone · stereo-EEG · SEEG · interictal · functional connectivity · edge matching · HUP · OpenNeuro ds004100