A bound from early voltage gave no valid 50 ms theta phase certificate in seven SEEG rest records

We tested an exact theta phase certificate on 28 contact pairs from seven public SEEG rest records. The test assumes that every unavailable voltage residual is within a bound from early voltage. With 50 ms of future input, four of 32,480 labels passed under the base bound. All four recorded continuations violated that bound. Thus, zero labels had both a certificate and a recorded continuation within the base bound. Observed phase agreement within 45 degrees was 80.37%. With 750 ms of future input, 97.99% passed the conditional test. A 1.5-times bound gave one certificate with its recorded bound satisfied at 50 ms. A 2-times bound gave none at 50 ms. The proof gives an exact test and an allowed future sequence that can break the phase tolerance. The result applies to the specified centered FIR filter, mean-fill estimate, and independent voltage bounds. It does not show that physiological phase prediction is impossible. The package preserves inputs, code, proof, source hashes, results, and three figures. Fresh full-file checks and an exact replay passed.

SEEG · theta phase · phase certification · finite impulse response filter · voltage bounds · signal processing · brain-computer interfaces