Shared-contact bipolar SEEG pairs retain a mean absolute correlation of 0.496 after contact time shifts at 1–45 Hz in 12 selected patients

We tested whether shared contacts produce strong zero-lag correlation in bipolar SEEG controls. We used one minute from each of two interictal recordings in the first 12 eligible patient IDs in OpenNeuro ds004100 version 1.1.3. At 1–45 Hz in run 01, independent circular shifts of the source contacts, followed by bipolar subtraction, gave a patient mean absolute correlation of 0.496 (0.492 to 0.500) in shared-contact pairs. The values in parentheses are 95% patient bootstrap intervals. A second shift of each constructed bipolar channel preserved its power spectrum and gave 0.032 (0.026 to 0.040). The patient mean paired difference was 0.464 (0.455 to 0.471). The package contains a contact-sharing mask, a variance control, source records, exact retrieval recipes, code, tables, and figures. The result shows a large dependence caused by shared contacts in this control. It does not measure neural coupling or the artifact fraction in recorded signals. The selected patients do not represent the full source cohort.

stereo-EEG · bipolar montage · shared contacts · correlation · circular shifts · signal processing · intracranial EEG · epilepsy