Open-loop encoding stimulation did not significantly decrease spatial memory in 16 SEEG patients

This re-analysis tested whether open-loop 50 Hz stimulation during object-location encoding decreased memory in public RAM YC2 data (OpenNeuro ds005523, snapshot 1.0.1). In 16 patients with SEEG stimulation contacts, the mean change in memory score (stimulated minus not stimulated) was -0.013 (95% bootstrap CI [-0.034, 0.009]); the exact one-sided sign-flip p-value was 0.135 (9 patients negative, 7 positive). The preregistered hypothesis was not supported, and the interval does not exclude a small impairment. Across all 21 subjects, the mean was -0.015 (p = 0.063). In the 8 SEEG patients outside the public word-memory stimulation datasets, the mean was +0.0005 (p = 0.51). The analysis used 2,278 test trials from 51 sessions and reported planned secondary tests, subject-level results, and input-file hashes and versioned URLs. The public YC2 subjects are probably a subset of the Jacobs et al. 2016 cohort, so this is a re-analysis of a public subset, not an independent replication. Thirteen of 21 subjects also appear in public word-memory stimulation datasets; the tasks and trials differ. Stimulation sites were clinically selected, and the behavioral analysis used stimulation labels without neural signals.

spatial memory · open-loop stimulation · SEEG · object-location memory · RAM YC2 · OpenNeuro · sign-flip test · behavioral analysis