Fig. 4: Differences across the brain in.

a PET amyloid load and (b) volume. The full sample compares all subjects in community 1 (i.e., CN dominant) to all subjects in community 2 (i.e., AD dominant), whereas CN and AD mismatches compare only CN (N = 123 vs. 27) or AD (N = 12 vs. 123) cases between communities. U-values were scaled (divided by maximum U) for ease of interpretation. Results were Bonferroni corrected unless otherwise stated (all except for volumetric findings in CN mismatched cases, which were FDR corrected instead). Masks were weighted using results of t-tests or Whitney–Mann U tests. These were based on ROIs from the Desikan-Killiany Atlas, and included the amygdala, nucleus accumbens, hippocampus, pallidum, thalamus, caudate, and ventral diencephalon (ventral DC).