Zero-time choices permitted both sex-adjusted age slope signs for two-back minus zero-back d-prime in ds005270 with positive-time choices fixed

We tested the age slope of corrected two-back minus zero-back d-prime in 158 adults from OpenNeuro ds005270 version 1.0.0. We fixed positive-time choices from accuracy under a valid two-choice task assumption. We permitted either binary choice at each eligible zero-time trial. These choices are sensitivity scenarios, not recovered responses. The exact sample bounds for the slope, adjusted for recorded sex, were -0.436 to +0.241 d-prime units per decade. Complete trial assignments attained both endpoints. Thus both signs were possible under the stated assumptions. A person bootstrap gave an approximate outer 95% set of [-0.569, +0.353]. All planned bound checks also permitted both signs. A later check split the recorded error age slope of +2.784 percentage points per decade into a zero-time contribution of +3.033 and a positive-time contribution of -0.249. This split does not establish a cause. The package includes the endpoint proof, source files and hashes, code, all assignments, all resampling records, figures, and run instructions. An independent check verified 460000 bootstrap values. A fresh source copy reproduced all 18 result and figure files exactly. The result does not show that age has no effect on working memory.

n-back task · working memory · d-prime · zero response time · sensitivity analysis · partial identification · exact bounds · age association · cognitive control · OpenNeuro