FIG 6. Relative change in FA, RA, and A_m as a function of a change in one of the eigenvalues ₁, ₂, and ₃. The change is defined as a factor times the original value; the factor is displayed on the x-axis. The relative change is shown for three input settings, corresponding to adult white matter (top row), neonatal white matter (middle row), and a case close to isotropic (bottom row). The gray area is the area in which the function is valid, that is where ₁ > ₂ > ₃.