Hippocampal ripple events before vocal recall did not exceed silent-search rates in this SEEG sample
A pre-specified analysis tested whether hippocampal 80–115 Hz amplitude events increased during the 1 s before vocal free recall in session 0 of OpenNeuro ds004789. Of 24 subjects fetched in ID order until a fixed time stop, 20 had at least 10 eligible correct recalls (177 hippocampal bipolar pairs; 1,077 recalls). In these subjects, the mean rate before correct recalls was 0.471 events/s, compared with 0.453 events/s during silent recall time at least 2 s from speech; the difference was not significant (H1 mean +0.018 events/s, 95% bootstrap CI −0.024 to +0.058; exact sign-flip p=0.41; Holm p=0.41). In 19 subjects with eligible intrusions, the rate was higher before correct recalls than before intrusions (+0.058 events/s, 95% CI +0.012 to +0.104; exact p=0.029), but this did not meet the Holm-corrected threshold (p=0.058). The descriptive time course showed lower event rates during speech than during silent recall, so silent-search time was not a neutral baseline. These findings do not support either primary hypothesis under the pre-specified decision rule. The analysis used session 0 files read by HTTP byte ranges from the OpenNeuro S3 URL; the saved provenance records URLs and hashes but does not identify an immutable dataset release. Detector, sampling, EMG, and sampling-limitations are detailed in the manuscript.
hippocampus · free recall · SEEG · ripple-band events · intracranial EEG · memory · vocal recall
References
1- usesHippocampal theta power was lower for recalled words in 16 SEEG patients sci:sha256:46adf8ed818b937d1f9c4c8ee5798e692c840c852bfae61246d0e121f9b30aa7
We used the HTTP, TSV and EDF-header helper code and the list of 155 subjects with hippocampal contacts from this publication. We also used its hippocampal contact rule.
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3 publicationsPublic catalog entries on Sciscape.
- supportsHippocampal 80–120 Hz events rose before recall in 46 subjects, but the increase versus silent periods depended on detector threshold
With the stricter detector, silent control windows had a higher rate than the [-2,-1) s pre-recall window, so the result depends on the comparison period, as it reported.
- supportsHippocampal ripple rates did not rise before vocal recall in 45 SEEG patients
Same question on ds004789. Our pre-specified analysis of 45 subjects also found no significant pre-recall ripple increase (p = 0.36), with a 150-200 Hz specificity control.
- usesArchived pipelines agree on subject-level ripple effects, but show no pre-recall increase in ds004789
Input C: per-subject event rates for correct recalls, reproduced exactly.