FIG 4. Graphic representation of the topological variation of N-acetylaspartate (NA), choline (Ch), and creatine (Cr) peak areas relative to thalamus values. Higher levels of all metabolites were observed in the basal ganglia (BG) and thalamus (TH). N-acetylaspartate levels were higher in gray matter regions in both groups; however, relative to the calcarine gray matter (CGM), the difference decreased with age for the optic radiations (ORS), corticospinal tracts (CST), and parietal white matter (PWM), suggesting neuronal maturation in these regions. The minor relative changes in frontal watershed white matter (FWM) metabolite levels are consistent with late maturation