The mean bipolar minus common average difference is +0.068 dB for median beta effects before keypresses in eight SEEG participants

We compared bipolar and common average references in all eight participants of OpenNeuro ds004473, version 1.0.2. We used 1786 correct trials and 834 adjacent contact pairs. Beta power was measured in the 0.5 seconds before a keypress and before fixation. The mean difference between participant medians was +0.068 dB for bipolar minus common average. The participant bootstrap 95 percent interval was -0.076 to +0.222 dB. The exact two-sided sign-flip p value was 0.468750. The test did not resolve a group mean difference. This does not establish equivalent effects. Pair sign agreement had a participant mean of 77.8 percent. No pair had opposite signs with effects of at least 1 dB in both methods. The package preserves trial powers, code, source metadata, range hashes, and instructions. These results apply to this task and clinical sample. The task window includes cue processing and preparation. It does not isolate movement. The comparison cannot identify a neural source or select a better reference.

stereoelectroencephalography · SEEG · beta power · common average reference · bipolar reference · electrophysiology