Figure 2.

Aggregate g-ratio maps derived using the two g-ratio approaches (NODDI-DTI- or NODDI-based approach), and corresponding absolute difference maps, from the brains of three participants of different age groups: young, middle-aged, and elderly. For each participant, results are shown for two representative slices covering the main cerebral structures studied. Results indicate that the g-ratio decreases until middle age and then increases through older adulthood. Further, derived maps from the two g-ratio approaches are similar, as quantified in Figure 3.