Figure 4: Ascorbic acid, another marker of oxidative stress. Box plots for levels of ascorbic acid in the brain, displaying the distribution of values within each of the four cohorts represented as a Whisker plot, with the relative normalized intensity as the abscissa. Mean values represented by the black arrowheads, median values by blue arrowheads. Detailed statistical comparisons of ascorbate in the four cohorts are given in Table 1.