Pre-Go-cue SEEG beta power did not predict key-press reaction time in 8 epilepsy patients (OpenNeuro ds004473, 80 trials each, 0.5-s window, mostly non-motor contacts)

We tested whether stereo-electroencephalography (SEEG) power in the 13–30 Hz beta band during the 0.5 s before a Go cue predicted reaction time (RT) in a cued forced-choice key-press task. Eight epilepsy patients contributed 80 trials each sampled at equal steps over the session; artifact rejection left 78–80 trials per patient. For the five bipolar pairs per patient with the strongest movement-related beta decrease, the group mean effect was +0.023 (SD 0.112) z(log RT) per z(power), with 6/8 subject effects positive (exact sign-flip p = 0.555; Holm p = 1.00). Across all pairs, the mean effect was −0.009 (SD 0.074; 4/8 positive; p = 0.703; Holm p = 1.00). For 70–110 Hz power at the five pairs with the strongest movement increase, the mean effect was +0.063 (SD 0.069; 6/8 positive; p = 0.055; Holm p = 0.164), opposite to the expected direction. Most electrode contacts were temporal or limbic, and selected beta pairs in six patients showed weak or no movement-related beta decrease. The result therefore does not exclude a beta–RT relation in primary motor cortex. With eight patients and 80 sampled trials per patient, effects smaller than about 0.1 SD per SD cannot be excluded.

stereo-electroencephalography · reaction time · beta power · high-frequency activity · motor preparation · sign-flip test · OpenNeuro