Pre-recall hippocampal HFA did not predict recall rate in FR1; the catFR1 association did not survive correction

We tested whether the size of the hippocampal 70–150 Hz high-frequency activity (HFA) increase before correct recall predicts recall rate across persons. We used archived per-person pre-recall HFA values from two independent, non-overlapping cohorts: FR1 (n = 95; OpenNeuro ds004789, ses-0) and catFR1 (n = 46; ds004809, ses-0). Per-person recall rates were calculated from ses-0 events.tsv files, with all 142 file hashes matching the hashes recorded in the earlier cohort analyses. A plan was written before recall rates and correlations were computed. Spearman correlations used two-sided permutation tests and Holm correction across the two cohorts. In FR1, rho = +0.086 (95% CI −0.109 to +0.280; p = 0.40). In catFR1, rho = +0.295 (95% CI −0.006 to +0.556; p = 0.047; Holm p = 0.095). The prespecified decision was no association because the larger FR1 discovery cohort did not show an association; its confidence interval excludes rho > 0.28. A weak positive association remains possible, and the catFR1 estimate was larger but did not survive correction. HFA values were archived and were not recomputed from EDF files; only session 0 was used. Between-person differences in electrode position, pair count, epilepsy, and medication may add noise. Hippocampal labels came from RAM atlas fields without image checks, and the HFA measure used recalls after a 2-s silent gap while recall rate included all recalls.

hippocampus · high-frequency activity · free recall · memory · recall rate · electrophysiology · between-person correlation · permutation test