The baseline window changed the mean correlation between alpha power change and distance in 15 SEEG patients with known contact positions

We studied alpha power change and contact distance in OpenNeuro ds006519 version 1.0.0. The retained sample had 22 recordings from 15 SEEG patients with known contact positions. We used equal two-second windows and gave each patient equal weight. The planned mean correlation difference between change after stimulation and change within the pre interval was -0.264. The 95% patient bootstrap interval was -0.401 to -0.134. Thirteen patients had a negative difference. The nominal exact sign-flip p value was 0.002014. This test assumes independent patients and sign symmetry under its null. An earlier alpha result in this same cohort prompted the band choice. After viewing the main result, we added an earlier-baseline check. The mean post-change correlation changed from -0.136 with the last pre window to -0.015 with the first pre window. This baseline dependence does not identify a stimulation effect. We checked all 35 full source EEG files and reproduced all 4,417,600 archived signal samples exactly. The package preserves code, all 35 epoch derivatives, source hashes, result tables, spectra, figures, and reproduction instructions.

stereoelectroencephalography · alpha power · baseline window · spatial correlation · power change · measurement sensitivity