Raw temporal derivatives reduced maximum contrast error on a ±1 s grid in 431 AOMIC designs with equal responses and a 0.2 mm motion limit
We tested response timing error in 431 public AOMIC working memory designs. The change and nochange responses had equal unit size under a defined response kernel. We removed row zero and scans above 0.2 mm framewise displacement. We tested independent condition delays from minus one to plus one second on a 0.1 second grid. Adding raw temporal derivatives reduced maximum contrast error in all 431 primary designs. The mean maximum error fell from 0.071675 to 0.045709 contrast units. The mean contrast variance increased by 3.47% under independent white noise. Finite error remained in every design. We provide exact finite grid witnesses, an analytic bound between grid points, and a reusable contrast weight method. An exact repeat and an isolated numeric repeat passed. The results apply to the specified scan clock, response kernel, contrast, and masks. The package contains source files, pinned retrieval recipes, code, results, and reproduction instructions.
functional MRI · hemodynamic response · temporal derivatives · contrast error · design audit · least squares · motion regressors · response timing
References
7- usesResponse-only removal of six motion terms reduced known unit contrasts in 431 fixed AOMIC v2.0.0 working memory designs after shared drift removal sci:sha256:061d9a1371b95e2dddc49d3124d269c10d26416b55b4f8728ff06b3f8fa82087
This study used its 431 complete working memory event and motion records. It also used four unchanged source and design code files. The new analysis tested contrast error from condition timing changes with equal response size.
- usesdoi:10.18112/openneuro.ds002785.v2.0.0
The analysis used 207 complete PIOP1 working memory event, motion, and scan metadata records from version 2.0.0.
- usesdoi:10.18112/openneuro.ds002790.v2.0.0
The analysis used 224 complete PIOP2 working memory event, motion, and scan metadata records from version 2.0.0.
- doi:10.1038/s41597-021-00870-6
- doi:10.1016/j.neuroimage.2008.10.065
- doi:10.1016/j.neuroimage.2003.12.029
- doi:10.1371/journal.pone.0126255
Cited by
4 publicationsPublic catalog entries on Sciscape.
- supportsUnder source row order, tests did not confirm outcome history effects in 14 SEEG patients and 29 fMRI adults
This earlier design study tested residual timing error with raw temporal derivatives. Our filter checks concern different schedules, software basis and a conditional history contrast.
- usesCue derivatives reduced maximum absolute false stop coefficients on a -0.5 to +0.5 s grid and raised standard errors with a fixed kernel and independent noise in 209 PIOP2 designs
This publication supplied prior method context for contrast weights and exact finite-grid response timing extremes. The new audit tests cue derivative nuisance terms for later stop-signal coefficients. No code or matrices from the working memory study were reused.
- usesNumerical bounds showed lower worst mean squared error than canonical and raw derivative fits in 431 AOMIC designs for amplitudes 0 to 1, delays ±1 s, and white noise SD 0.2
This study used the complete archived task events, motion tables, scan metadata, fixed source records, retrieval programs, response kernel code, nuisance design code, and component curvature bound code. It extends the earlier equal-response audit with three independently bounded condition amplitudes and optimized scan weights.
- usesOptimized weights reduced conservative 95% interval widths in 431 AOMIC designs under a fixed response model with [0,1] amplitudes, ±1 s delays, and known Gaussian noise
This publication supplied the exact AOMIC events, selected motion columns, image metadata, six unchanged code files, and the analytic response model. Its timing error results informed the question. The new study permits all three amplitudes to vary independently and selects weights for intervals.