Patient-level SEEG memory effects did not reliably track recall rate in one free-recall session

In 51 patients with pure SEEG data from one delayed free-recall session, the patient-level subsequent memory effect (SME) did not correlate significantly with recall rate after Holm correction. Spearman correlations were -0.02 for high-frequency activity (HFA, 70–150 Hz; 95% CI -0.30 to +0.28), +0.26 for theta (3–8 Hz; -0.01 to +0.49), and -0.24 for HFA-minus-theta tilt (-0.49 to +0.04); adjusted p values were 0.89, 0.20, and 0.20. Split-half reliability of the patient-level SME was low (Spearman–Brown 0.06, 0.23, and 0.26). The HFA interval excludes correlations of magnitude 0.4 or greater, while the theta and tilt intervals do not exclude a moderate relationship. Age was associated with lower recall across 54 patients (rho -0.36, 95% CI -0.58 to -0.10, p=0.009). Group effects after list and serial-position removal were near zero for HFA (+0.004 d, p=0.56), negative for theta (-0.027 d, p=0.019), and positive for tilt (+0.026 d, p=0.018). These findings indicate that, in this single session and with this all-pair measure, patient-level SME size is an unreliable trait marker; low reliability limits interpretation of null correlations. The exact release of the OpenNeuro source data could not be confirmed from the archived acquisition URLs and hashes.

SEEG · subsequent memory effect · free recall · memory ability · individual differences · split-half reliability · theta · high-frequency activity