Summed concentrations (a) and concentration ratios (b) of selected pairs of metabolites (Gln and Glu, PCr and Cr, GPC and PCho) that are difficult to resolve at lower magnetic field strengths (mean ± SD). Metabolites quantified from striata of R6/2 and wild type mice at 8 and 12 weeks of age. Statistically significant differences are shown for comparisons between R6/2 and wild type mice at each age. Significance level: *p < 0.05, **p < 0.01, ***p < 0.001. Additionally, significant differences between 8 and 12-week-old R6/2 mice were found for Gln + Glu (p < 0.001), GPC + PCho (p < 0.001), PCr/Cr (p < 0.01) and GPC/PCho (p < 0.001).