A left/right SEEG decoder did not increase information over a rest/move detector in 15 patients

In a pre-registered offline analysis of 15 patients from OpenNeuro ds006253, we compared a rest/move detector (D2), a hierarchical rest/left/right decoder (H3), and a flat three-class decoder (F3) using 70–150 Hz SEEG high-gamma window means and shrinkage LDA. Mean Miller–Madow-corrected information was 0.263 bits per decision for D2, 0.267 for H3, and 0.256 for F3. The H3–D2 difference was +0.0045 bits (95% bootstrap CI −0.0005 to +0.0116; exact one-sided sign-flip p = 0.090; Holm p = 0.18); the F3–H3 difference was −0.0109 bits (CI −0.0231 to +0.0011; two-sided p = 0.111; Holm p = 0.18). Neither hypothesis was supported. The real direction stage yielded 1.2% of the gain estimated for a perfect direction stage. Mean held-out direction AUC was 0.561, and one patient had a large gain (sub-14: AUC 0.80, +0.046 bits). With these features and this linear decoder, the three-output decoder acted in practice like a rest/move switch. This offline study used onset-aligned windows from one session per patient, one feature type, and 15 patients; it does not establish real-time performance.

SEEG · brain-computer interface · movement decoding · direction decoding · high-gamma activity · mutual information · shrinkage LDA · OpenNeuro ds006253