Extended Data Fig. 7: CBF declines nonlinearly with age over the lifespan.

Evolution of gray matter CBF with age over the lifespan across all five datasets. For each dataset, we used four methods for quantifying CBF: the standard CBF model (see main text), BASIL (a), BASIL with partial volume correction (PVC; b), and SCRUB (c). We used a generalized additive model with penalized splines to characterize the nonlinear evolution of CBF over age. The thick black line represents the predicted values, while the dashed lines represent the 95% confidence intervals.