Hippocampal theta and HFA power did not predict later object-location error during passive encoding in 24 YC1 participants

During passive transport in the RAM YC1 virtual navigation task, this analysis tested whether hippocampal bipolar SEEG power during encoding predicted later object-location error. It used session 0 of OpenNeuro ds005522 v1.0.0: 24 participants, 132 hippocampal pairs, and 1,047 trials. No band was supported. For theta (3–8 Hz), mean Fisher z was −0.027 (95% CI −0.073 to +0.018; Holm p = 0.393); for high-frequency activity (70–150 Hz), mean z was +0.027 (95% CI −0.012 to +0.065; Holm p = 0.393). Delta, alpha, and beta were also not significant. Robustness analyses using trial-adjusted effects, raw error, non-hippocampal pairs, and left/right hippocampal pairs gave the same overall result. The confidence intervals for the primary effects were within ±0.075, so group mean effects larger than about |z| = 0.075 are improbable in this sample; smaller effects are not excluded. The result concerns two 5-second passive encoding epochs in session 0 and does not apply to active navigation or retrieval. The behavioral measure was informative: 24 of 29 participants with signal and events performed better than chance (mean normalized error 0.327; sign-flip p = 2 × 10⁻⁵).

spatial memory · hippocampus · SEEG · theta power · high-frequency activity · subsequent memory effect · virtual navigation · OpenNeuro ds005522