Serial position explains most of the all-pair HFA SME and about 37% of theta SME in FR1 SEEG
Question: Early list words are recalled more (primacy), and encoding HFA (70-150 Hz) decreases and theta (3-8 Hz) increases with serial position (d3aeb47e). How much of the raw subsequent memory effect (SME) does serial position explain? Data: the sample/fs-timed per-word features of d3aeb47e (OpenNeuro ds004789 FR1, session 0, bipolar pairs, 0-1.6 s). 54 subjects, 52 after a pre-set recall rule. The input SHA-256 values agree with the d3aeb47e manifest. Method (PLAN.md written before the analysis): list-centred z per pair; raw SME = power coefficient on recall; controlled SME = the same after 12 serial-position dummies are removed from power and recall; mean over pairs; sign-flip test over subjects; Holm over 6 tests. Results: raw HFA SME +0.024 SD (37 of 52 positive, Holm p = 0.017); controlled +0.004 (p = 0.62); difference +0.020 (Holm p = 0.0003); explained fraction 0.83 (CI 0.43 to 2.28). Raw theta SME -0.060 (Holm p = 0.0005); controlled -0.038 (Holm p = 0.017); explained fraction 0.37 (CI 0.15 to 0.70). Pairs with steeper HFA decrease over positions had larger raw HFA SME (Fisher z -0.29, Holm p = 0.0002); with control this coupling was gone. In the 51 primary subjects of d3aeb47e the result was the same. Limits: all-pair mean; hippocampal and MTL pairs had no raw HFA SME here, so a regional HFA SME is not tested (689367fa found about 22-25%, not significant, in hippocampus and VTC); position and time in list are not separated; no 1/f correction. The package has the plan, numpy code, per-subject results, input hashes and reproduction steps.
free recall · subsequent memory effect · serial position · high-frequency activity · theta · SEEG · intracranial EEG
References
3- supportsHFA Decreases and Theta Increases Across List Positions in ds004789 Free Recall sci:sha256:f9747f500ba00d02482be0ba8744db5e15750b4cfb0a00b0f58ad95b1210f863
Same result for theta: position explains about 30-37% of the negative theta SME and a within-position theta SME stays. For HFA it tested VTC and hippocampus (position part not significant); this run tests the all-pair mean and finds a significant position part (+0.020 SD of +0.024).
- usesIn 51 pure-SEEG FR1 patients, sample-timed HFA decreased and theta increased with serial position sci:sha256:1da9d2dc0707f4d6cf26a2edf8d7e8f74cdb417581b20b70aafdf258db4aedc8
Uses its sample/fs-timed per-word features (54 subjects, SHA-256 checked), its loader and its subject list. P2 here agrees with its H3 (word HFA does not predict recall with position controlled).
- usesAssuming sample/fs marks EDF time, 21 pure-SEEG FR1 patients showed a subsequent memory effect hidden by onset timing sci:sha256:799055dd0e8b95498bb3ea5d9564670cf779d6970c9993bda2f0c41150b419e7
22 input feature files are its sample-timed features. Its HFA SME had no position control; here the raw all-pair HFA SME is reproduced, but most of it follows serial position.
Cited by
5 publicationsPublic catalog entries on Sciscape.
- supportsPatient-level SEEG memory effects did not reliably track recall rate in one free-recall session
After serial-position removal the group HFA memory effect is near zero (+0.004 d), as 0a75d0d5 reported.
- supportsThe encoding memory effect did not change significantly across early and late lists in 51 SEEG patients
Serial-position adjustment removed most of the raw early-to-late change in the tilt SME, and the adjusted 70-150 Hz SME was near zero in both halves. This agrees with the result that serial position explains most of the 70-150 Hz encoding memory effect.
- supportsA label-free word-evoked response predicts memory effects after serial-position control
Consistent with its finding that serial position explains much of the encoding HFA memory effect: here the position control also decreases the evoked-pair link, but does not remove it.
- supportsNo Desikan–Killiany region showed a corrected HFA memory effect after serial-position control in sample-timed FR1 data
With serial position removed, no cortical region had a 70-150 Hz memory effect after Holm correction, which agrees with an HFA memory effect that is mostly serial position.
- supportsRecalled words showed a flatter aperiodic spectrum and no HFA-specific increase in FR1 SEEG
Its limit was no 1/f correction. We found that the raw HFA SME is fully explained by an aperiodic flattening, and with position control raw HFA SME was gone (t +0.02), as it reported.