OpenNeuro ds004789 contains 17 non-right-handed and 81 right-handed bilateral pure-SEEG patients for an SME lateralization test, with minimum detectable d = 0.75

This pre-registered feasibility audit asked whether OpenNeuro ds004789 can test whether handedness changes left-right lateralization of the encoding subsequent memory effect (SME). It counted patients and estimated the minimum detectable effect; it calculated no memory-effect statistic. In the FR1 session 0 data, pure SEEG patients had at least one SEEG channel and no ECOG channels. Bilateral coverage required at least three MNI152NLin6ASym electrode contacts with x < 0 and at least three with x > 0. Of 229 right-handed participants, 179 had FR1 session 0 files, 112 had pure SEEG, and 81 had bilateral coverage. Of 44 non-right-handed participants (left-handed or ambidextrous), the respective counts were 42, 25, and 17 (14 left-handed, 3 ambidextrous). Four of seven participants with unavailable handedness had bilateral pure-SEEG coverage. For the full dataset, the planned two-sample normal-approximation estimate was d_min = 0.747 (reported as 0.75; two-sided alpha 0.05, power 0.80), meeting the feasibility rule of at least 10 non-right-handed patients. In the archived 54-subject feature cohort, only 3 non-right-handed patients met the region-label bilateral rule (d_min = 1.763); under the MNI-x rule, 5 did (d_min = 1.37). A test therefore requires new feature extraction for all 98 bilateral pure-SEEG subjects, and would detect only large differences. Self-reported handedness is a weak proxy for language dominance, which dilutes the contrast; a null result cannot exclude moderate effects. Other limitations are contact rather than bipolar-pair side assignment, possible misassignment near x = 0, an arbitrary three-contact threshold that differs from an earlier pair-level rule, and a normal approximation assuming one primary test.

handedness · stereo-EEG · SEEG · subsequent memory effect · lateralization · feasibility · minimum detectable effect · OpenNeuro ds004789