C4B and major depressive disorder: Notably, 58% of the WM tracts identified as significantly altered in MDD in our primary analysis remained detectable in this motion-controlled subsample, including the ATR, CH, Fmin, Fmaj, ILF, and SLF (|Cohen's d| > 0.19, P < 0.013, FDR q < 0.05, Fig. S9 and Table S10).