Fig. 2.

VBM demonstrating significantly positive correlation with fatigue scores across the whole group. The significant cluster (top-left) consisting of 3547 voxels (k_E= 3547), comprised of: Left – PCC, PRC, SPL and Right - PRC with peak t-score of 4.74 and exact corrected p-value of p_FWE = 0.019 at MNI coordinates: [-16 -54 48]. The axial slices (bottom) show the spatial extent of the same cluster over finer slices. The scatter plot (top-right) with the linear regression line shows significant positive correlation of GMV with self-reported fatigue score across the whole group (ρ = 0.34, p = 0.016, r²= 0.11). Please note, the ρ represents Spearman's rank-order correlation coefficient. The light pink colored dots represent the COVID subjects, and the cyan dots represent the HCs. The COVID group clearly demonstrates higher effects than the HC group. Please note, the GMV in the x-axis represents the residuals plus the mean GMV of the cluster across subjects added back after linear regression. Keys: PCC = Posterior Cingulate Cortex, PRC = Precuneus, SPL = Superior Parietal Lobule. The linear plot (blue) represents the least squares regression line (best fit), and the shaded gray area represents the 95% confidence interval. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)