Widening bipolar span from one to three contact intervals increased theta to high gamma power ratios in two resting SEEG records

We tested bipolar span in both resting SEEG records from OpenNeuro ds005670 version 1.0.0. The two records came from patients with epilepsy. We compared one and three contact intervals in 313 groups of four consecutive contacts. Each pair had the same midpoint in contact order. The nominal spans were 3.5 and 10.5 mm. Each record supplied 400 seconds of data. The tested ratio used 4 to 8 Hz power and 70 to 140 Hz power, with 98 to 102 Hz removed. We took the median ratio change within each shaft, then the mean across shafts. The changes were 3.21 and 3.14 dB. All 20 block values and all six planned checks were positive in each record. Only 44 percent and 50 percent of the top-ranked groups were shared across spans. A constant distance scale cannot change a power ratio. The package includes a spectral sum comparison, code, compact spectra, all result tables, fixed source hashes, and a raw retrieval recipe. A separate byte reader and SciPy Welch passed selected checks. A full repeat matched all 16 data and numerical result files by hash. The findings apply to these two records. They do not estimate a population effect or establish a new general spacing mechanism.

stereoelectroencephalography · bipolar referencing · contact spacing · power spectral density · theta · high gamma · OpenNeuro