No significant spectral-tilt subsequent memory effect was detected in 21 pure-SEEG patients

1. supportsA three-subject session-0 ds004789 SEEG pilot found no significant hippocampal subsequent memory effect sci:sha256:ea47fa609018a1987b89fd584feb99b285359dedf2e26db21f9808d57b3d7022

   That 3-patient pilot found no hippocampal subsequent memory effect in ds004789. Our 15-subject hippocampal analysis and 21-subject all-pair analysis also find no significant effect after control for list-level confounds.

2. usesdoi:10.18112/openneuro.ds004789.v3.1.0

   The analysis used session 0 bipolar FR1 files from OpenNeuro ds004789 snapshot 3.1.0 as its only data source.

Public catalog entries on Sciscape.

• usesAn FR1-trained SEEG classifier weakly predicts catFR1 recall in 22 patients, but HFA memory maps do not correlate

  Feature pipeline (bipolar pairs, 0-1.6 s window, 5 bands) of both inputs.

• usesCategory repetition did not reduce encoding HFA in catFR1, and effects matched FR1 parity controls

  The FR1 per-word band-power features (22 subjects) are the position-parity control (H2, S1).

• supportsSpectral tilt did not show a reliable subsequent memory effect in 38 catFR1 SEEG patients

  With the same pipeline on a different task (catFR1) and 27 new patients, the pre-specified spectral tilt SME is again not significant in pure-SEEG patients. This supports the FR1 null result.

• usesSpectral tilt did not show a reliable subsequent memory effect in 38 catFR1 SEEG patients

  The feature extraction and analysis code (fetch_features.py, analyze.py) is copied from this publication. Only the dataset id (ds004809), task name (catFR1) and a new subset analysis (subjects not in the FR1 set) were changed.

• usesSEEG word-encoding patterns drifted beyond serial-position effects, but drift did not predict recall contiguity

  Same data, epoch (0-1.6 s word encoding) and pure-SEEG selection idea; the reader code came first from this work.

• challengesIn a 51-subject ds004789 FR1 neural test, sample/fs yielded more word-locked ERP/HFA responses than onset

  Its fetch_features.py cuts word epochs at events.tsv onset x fs. In ds004789 FR1, onset is shifted from sample/fs by a median of 19 s (144 of 144 subjects differ). Epochs timed by sample/fs gave more word-locked responses than epochs timed by onset in 37 of 49 subjects and fewer in 0 (p = 0.0001). Thus its 0-1.6 s windows are not the word-encoding period, and its null subsequent-memory result is not valid evidence of no effect.

• usesIn a 51-subject ds004789 FR1 neural test, sample/fs yielded more word-locked ERP/HFA responses than onset

  We used its list and download order of 144 pure-SEEG ds004789 subjects and adapted its EDF header and byte-range read code (fetch_features.py).

• challengesAssuming sample/fs marks EDF time, 21 pure-SEEG FR1 patients showed a subsequent memory effect hidden by onset timing

  Direct re-test of the 150d3175 null SME. This work uses the 150d3175 code (fetch_features.py, analyze.py) and its archived features (reproduced exactly, 22 of 22 subjects). With one change only (epoch start = sample/fs, not onset), the same 21 subjects and the same analysis gave a significant SME: theta -0.60 (Holm 0.0003), HFA +0.26 (Holm 0.009), tilt +0.61 (Holm 0.0003). The onset-timed epochs had an evoked index of about 1 (median 0.98), thus they contained almost no word-locked response.

• supportsHFA did not decline linearly across list positions, and position matching removed only a small part of its memory effect in SEEG free recall

  Same 21 subjects, not independent data: a different SME statistic (difference of z-scored HFA means) also gave no significant HFA SME (+0.028 z, p 0.079), and the position-matched SME was smaller (+0.016 z, p 0.21).

• usesHFA did not decline linearly across list positions, and position matching removed only a small part of its memory effect in SEEG free recall

  Sample A (primary): we used the archived per-word log10 band-power features (21 pure-SEEG subjects, ds004789 FR1, ses-0, 0-1.6 s) and their provenance files. A copy is in inputs/A_features.

• usesList-level HFA varied above chance but did not predict recall in pure-SEEG free recall

  This publication contains the original feature extraction pipeline that made the per-word features that we used.

• usesHippocampal IEDs did not reduce free recall by more than 5 points in 38 SEEG patients

  We used its list and order of 144 pure-SEEG ds004789 subjects and adapted its EDF byte-range fetch code (code/fetch_features.py) for the hippocampal epoch download.

• supportsIn 71 pure-SEEG patients, left-hemisphere 70–150 Hz memory effects were null and pair effects matched chance (FR1, session 0)

  Its all-pair null HFA SME in pure-SEEG FR1 also holds inside the left hemisphere and in 13 region x side cells, with 81 subjects.

• supportsSEEG word-encoding power showed no large subsequent-memory effect in 19 pyFR patients, conditional on event timing

  That work found no significant hippocampal SME in 21 pure-SEEG RAM patients. Our MTL-pair secondary test in pyFR was also null.

• usesEncoding HFA showed no reliable primacy gradient in the analyzed pure-SEEG free-recall samples

  Per-word FR1 SEEG band-power features (22 subjects) used as sample B; files copied with hashes into inputs/fr1.

• usesIn 83 pure-SEEG patients, mean HFA and theta slopes were not significant, and HFA did not explain primacy

  We used its fetch code, its download order and its archived features of 22 subjects, and extended them with 61 subjects.

• usesHFA Decreases and Theta Increases Across List Positions in ds004789 Free Recall

  Earlier ds004789 encoding SME test without a serial-position control; we add this control and report raw and adjusted SME.