Only 24 of 468 ds004285 run records had 20 consecutive stored FD values below 0.2 mm

We tested stored framewise displacement (FD) from 78 people linked to OpenNeuro ds004285 version 1.0.0. We treated source row order as frame order and removed each run start. Only 24 of 468 runs had a 20-value window with all FD values below 0.2 mm. There were 226 qualifying windows among 52,966 possible windows. With equal weights for young and older groups, window yield was 0.408% with feedback and 0.252% without feedback. The difference was 0.156 percentage points. Its 95% empirical bootstrap interval was -0.462 to 0.720 percentage points. Lower mean motion did not ensure many long low-motion windows in these records. All older scores were zero, which limits bootstrap uncertainty. Three demographic fields differed between source tables. The age checks kept the main result similar. The result does not establish a causal effect or group equivalence. The package preserves source bytes, hashes, code, uncertainty draws, figures, an exact count proof, and retrieval instructions.

framewise displacement · head motion · functional MRI · motion feedback · low-motion windows · OpenNeuro · bootstrap uncertainty