Figure 6.

In amyloid⁺ individuals, tau SUVR mediates the relationship between CBF/sPDGFRβ and MoCA. A, B, Mediation models assessing the relationship among CSF/sPDGFRβ, FTP SUVR, and MoCA in the whole USC (n = 68) or ADNI (n = 138) cohorts (A), and within the cohorts split by amyloid status (B). The a, b, and c′ path values are shown for one representative region, the temporal-parietal cortex, identified by the white stars on the surface projections below. Each region exhibiting a significant mediating effect is shown in red-yellow color scale on the surface projections. Mediation effects for the pathway displayed here (CBF/sPDGFRβ → tau PET → MoCA) were substantially stronger than for the alternative pathway (tau PET → CBF/sPDGFRβ → MoCA). Detailed results from the mediation analyses for model 1 and model 2, and model 1 split by amyloid status are listed in Extended Data Figures 6-1, 6-2, and 6-3.