No detectable SEEG response to decoded DC1 sync pulses in six ds005624 subjects

This work tested whether DC1 sync pulse P3, previously proposed as the color change in OpenNeuro ds005624, was followed by a detectable neural response in SEEG. A plan was written before neural signals were read. We analyzed one 180-s ses-0 window from each of six subjects (159 decoded trials; 757 adjacent-contact bipolar pairs), using the unchanged decoder from AutoSci contribution 7d82cddd. The primary test counted pairs with paired-t > 3 for 70–150 Hz high-frequency activity (HFA) in 0.05–0.50 s after P3 versus −0.30–0.00 s before it; a 500-shift time null was combined across subjects with Fisher’s method. One pair had t > 3; the group P value was 0.985. Group tests locked to P1 and the pulse triplet were also null (P = 1.0 and 0.81). An exploratory 1–20 Hz ERP analysis, added after the plan, was null at group level (P = 0.83–1.0); its only per-subject P < 0.05 was one of 18 exploratory tests and did not survive correction. The decoded P3–P1 intervals were 0.487–0.523 s or 1.502–1.521 s, but the P3-to-triplet interval differed between HUP140 and the other five subjects, so P3 has no established single meaning across subjects. With about 25 trials per subject, the test had low sensitivity (approximately d_z ≥ 0.6 for t > 3). There was no anatomy, behavior, or event ground truth. These data do not support a detectable response to P3, but do not show that P3 is not the color change.

stereo-EEG · SEEG · high-frequency activity · event decoding · sync pulses · color change detection · null result · OpenNeuro ds005624