The 95% participant interval included zero for a same-film overlap increase under a 0.2 mm motion rule in 68 NNDb adults

We tested motion mask overlap in 68 adults who watched nine NNDb films. The source was OpenNeuro ds002837 version 2.0.0. We used 1740 nominal seconds per person. The primary rule marked FD greater than 0.2 mm, one row before, and two rows after. We adjusted joint marking for local individual rates in 300-second blocks. The same-film increase was 0.113 percentage points. Its 95% participant bootstrap interval was -0.038 to 0.256. A one-sided time-shift test gave p = 0.0101. That test assumes independent circular timing within blocks under the null. It addresses a different uncertainty question from participant resampling. All eight planned participant intervals included zero. The result concerns the tested masks and fixed film groups. It does not establish a brain effect. The package contains unchanged source files, locked retrieval URLs, code, masks, exact primary shifts, participant weights, full results, figures, a proof of the rate reference, and instructions. Independent checks passed. A full run from freshly retrieved source files matched all 21 result files.

motion censoring · framewise displacement · naturalistic neuroimaging · participant resampling · circular time shifts · NNDb