GFEX-EEG Validation Database: Brainstorm-tagged head models with manual helix-tragus-junction fiducials

Processed Brainstorm head-model database used to validate the GFEX-EEG toolbox (Geodesic Fiducial Extrapolation for MRI-free EEG source imaging). For four per-subject EEG–MRI cohorts it provides the imported, defaced structural MRIs, the derived Brainstorm anatomical surfaces, and the manually-tagged helix-tragus-junction (HTJ) ground-truth fiducials (Brainstorm SCS fiducial structures, with SCS.LPA/RPA holding the left/right HTJ) that underlie every accuracy number reported in the GFEX-EEG manuscript. Each cohort is provided as a self-contained, Brainstorm-loadable ZIP archive (a complete Brainstorm protocol with anat/ and data/ folders): • LEMON — MPI-Leipzig Mind-Brain-Body (OpenNeuro ds000221 / NITRC Fcon_1000; Polhemus digitizer) • Wakeman-Henson — subject-correct "rescued" EEG–MRI pairing (OpenNeuro ds000117 + ds002718; Neuromag/Elekta) • Shirley Ryan AbilityLab — TMS-EEG-MRI-fMRI-DWI (OpenNeuro ds004024; BrainProducts CapTrak) • MULTI-CLARID — Leibniz Institute, Magdeburg (OpenNeuro ds005795) Ground-truth convention: the helix-tragus junction was tagged manually in Brainstorm's MRI viewer for every MRI-bearing subject; in each subject's anat/.../subjectimage_*.mat the fields SCS.LPA and SCS.RPA hold the left/right HTJ (not the conventional pre-auricular point), and SCS.NAS is the standard nasion. All reported GFEX-EEG errors are therefore true HTJ accuracy. Privacy: all structural MRIs are defaced. They are imported unmodified in facial content from source datasets that distribute them already defaced (LEMON; Wakeman-Henson; OpenNeuro-mandated defacing for ds004024; pydeface for ds005795), confirmed by source documentation and by direct visual inspection across all four cohorts. The brain is preserved; the identifiable facial surface is removed. Licensing: the GFEX-EEG curation layer in this record — the manual HTJ tagging, the Brainstorm head-model organization, and the selection/compilation — is released under CC BY 4.0. The underlying source neuroimaging data remain under their original public-domain dedications (LEMON: PDDL; Wakeman-Henson, Shirley Ryan, MULTI-CLARID: CC0) and are not relicensed. Please cite both this record and the original source datasets (see the included README.md). Related resources: GFEX-EEG toolbox (https://github.com/michaelmcmahon/GFEX-EEG; Zenodo concept DOI 10.5281/zenodo.20580898) and the GFEX-EEG paper-analysis bundle (https://github.com/michaelmcmahon/GFEX-EEG-paper-analysis; Zenodo concept DOI 10.5281/zenodo.20800437).