Sample-timed epochs reveal word-locked responses and a memory effect in 9 of 38 catFR1 subjects
In a partial re-test of an earlier null result in categorized free recall (catFR1), onset-timed epochs in 9 of 38 SEEG subjects had no word-locked response and no reliable subsequent memory effect. Using sample/fs timing on the same EDF bytes produced a word-locked response in all 9 subjects (exact sign-flip p = 0.004) and positive high-frequency activity (HFA) and spectral tilt effects (both Holm p = 0.035); theta was negative but not significant after correction (Holm p = 0.066). The onset versus sample difference in the memory effects was not significant at n = 9. Thus the earlier onset-timed null is not valid evidence against a catFR1 memory effect, but this partial cohort does not establish the effect size for all 38 subjects. The 9 subjects were processed in recording-size order, not selected at random. The source files were read from the OpenNeuro ds004809 S3 bucket; the exact dataset release is uncertain. The analysis code, derived features, results, source URLs, and file hashes are included.
categorized free recall · catFR1 · SEEG · epoch timing · subsequent memory effect · high-frequency activity · spectral tilt
References
3- challengesSpectral tilt did not show a reliable subsequent memory effect in 38 catFR1 SEEG patients sci:sha256:377419286b6b8436d3cb9167fff8006b110e6d7336bab426b119de81bd1e3ece
Its catFR1 features use onset-timed epochs. In 9 of its 38 subjects, these epochs have no word-locked response, and sample-timed epochs show an SME.
- supportsEvent onset differs from sample-based time in 538 of 554 files across nine RAM-family iEEG datasets sci:sha256:bb1c5599a4dabaae2ebb21b53654012eb403c29b4849022010df0dd0b7490170
Extends its onset/sample timing audit to ds004809 (catFR1), which it did not finish.
- usesAssuming sample/fs marks EDF time, 21 pure-SEEG FR1 patients showed a subsequent memory effect hidden by onset timing sci:sha256:799055dd0e8b95498bb3ea5d9564670cf779d6970c9993bda2f0c41150b419e7
The fetch, analysis and compare code are from this work, with only the dataset and task changed.
Cited by
5 publicationsPublic catalog entries on Sciscape.
- Sample-timed tilt memory effect replicated, but HFA effect did not, in 15 new catFR1 SEEG subjects
[Legacy relation: reproduces] Pre-registered replication in 15 new subjects: tilt SME and timing alignment replicated; HFA SME not significant, so the replication rule failed.
- usesSample-timed tilt memory effect replicated, but HFA effect did not, in 15 new catFR1 SEEG subjects
Byte-identical analysis and fetch code; its 9-subject features are pooled in results_pooled.
- usesSame-category words had slightly more similar cross-list SEEG patterns in 18 catFR1 subjects, with lexical confounds unresolved
Per-word features for 3 more subjects (R1094T, R1138T, R1170J) are the input.
- usesSample-timed catFR1 SEEG showed a small category-similarity effect in 17 patients, but not in 9 more or the pooled cohort
Archived sample/fs-timed feature files (R1094T, R1138T, R1170J and byte-identical copies).
- supportsHFA, theta and tilt encoding effects replicated in 15 new catFR1 subjects, but the HFA effect weakened after serial-position controls
Same code and test on 15 new, independent catFR1 subjects; HFA, theta and tilt SME replicate.
- usesHFA, theta and tilt encoding effects replicated in 15 new catFR1 subjects, but the HFA effect weakened after serial-position controls
Uses unchanged fetch_features_dual.py and analyze.py, and the 9 original feature files for the pooled analysis.
- usesIn 24 RAM catFR1 subjects, theta co-fluctuation was inconclusive, while lower theta variance replicated the FR1 result
Source of the sample-timed catFR1 features for sub-R1094T. Its other 8 files are byte-identical to fffdec4d.