Fig. 4.

Top Panel: Hemispheric 3D maps of significant negative associations between 2-year change in VV and cortical GM thickness in matched N=100 sub-samples for AD, MCI, and healthy elderly individuals, after controlling for age and sex (AD: 2-year change, left: −log₁₀(p-values)=2.58–4.84, right: not significant; MCI: 2-year change, left: −log₁₀(p-values)=2.15–4.41, right: not significant; Controls: 2-year change, left: not significant, right: −log₁₀(p-values)=2.28–4.54, corrected). Results are corrected for multiple comparisons by thresholding at a q=0.05 false discovery rate (FDR) threshold across the entire brain surface. Blue represents areas where p-values passed the corrected significance threshold for a negative relationship between ventricular enlargement and cortical thickness values (greater VV enlargement associated with lower cortical GM thickness at baseline).

Bottom Panel: Plots of 2-year VV change against mean baseline GM thickness (x-axis: raw 2-year VV change in mm³, y-axis: mean baseline GM thickness for statistically significant regions in mm). Each data point represents one subject within the matched N=100 subsets for AD, MCI, and healthy elderly control groups (AD: first row, MCI: second and third rows, Controls: last two rows). Each plot represents a distinct and continuous cortical region that passed correction with FDR in the surface GLM maps shown in the top panel of this figure. Within each statistically significant cortical region, GM thickness was averaged across all significant surface vertices. Letters correspond to labels on the cortical surface maps in the top panel and are ordered first by group (AD: A–D; MCI: E–J, controls: K–R) and then by cortical region (from highest to lowest corrected p-value, all passed FDR in GLMs).