Fig. 4.

The inverted-U component spatially corresponds to the structural pattern of abnormalities in Alzheimer’s disease and correlates with episodic memory in healthy subjects. (A) The spatial network corresponding to the inverted-U component IC4 (orange) closely matches the gray matter found to be atrophic in Alzheimer’s disease compared with healthy elderly (blue; thresholded for better visualization at P < 0.001; n = 120; voxel-by-voxel spatial cross-correlation: r = 0.55; P < 10⁻³). (B) The inverted-U component load for each of the healthy participants plotted against episodic memory score (CVLT long-delay recall; n = 370; linear fit is in turquoise; r = 0.31; P = 1.2 × 10⁻⁹) (SI Materials and Methods). Results presented here have not been age-corrected, as the relationship between episodic memory scores and age was highly nonlinear. In fact, their lifespan trajectory matched that of the inverted-U component (Fig. S6), explaining the linear relationship between the two presented in B. a.u., arbitrary unit.