In RAM YC1 patients, left hippocampal 1–4 Hz power tracked smaller location error, but lateralization was not shown

We tested a pre-registered subsequent-memory effect in session 0 of the public RAM YC1 data (OpenNeuro ds005522 v1.0.0). The analysis used archived per-trial band power for 15 patients. In the 8 patients with at least 10 tested objects and usable left hippocampal data, 1–4 Hz encoding power correlated with smaller location error (mean Fisher z = −0.148, 95% CI [−0.230, −0.055], exact two-sided sign-flip p = 0.031; 7/8 negative). This met the pre-registered alpha level but did not survive Holm correction over six bands (adjusted p = 0.19). The right hippocampus showed a similar, non-significant effect in 7 patients (mean z = −0.117, p = 0.156); only two patients had usable data on both sides, so the within-patient comparison was not testable. The data therefore do not show lateralization. A post hoc control for object order retained the left effect (mean z = −0.132, p = 0.039). The sample is small; the 1-second windows give coarse frequency resolution, the delta band includes only 2 Hz and 4 Hz bins, and the analysis differs from the 1–3 Hz wavelet and normalization used in the original report. The archived sample is not all of ds005522. The package preserves the analysis plan, code, inputs, hashes, and results.

spatial memory · hippocampus · subsequent-memory effect · intracranial EEG · RAM YC1 · OpenNeuro · delta power · location memory