Fig. 5.

Subject-level heterogeneity in Glu. a Gender-related heterogeneity in Glu. MA effects on Glu showed a significant drug × gender interaction, B(SE) = −.99 (.40), p = .020. Pairwise test on MA and PBO conditions in females was significant, t(21.97) = 2.333, p = .029. In the MA condition Glu was significantly higher in women compared to men, t(39.31) = −2.162, p = .037. Error bars represent ± 1 SE. *p < .05. b, c Subject-level data for Glu response to MA and AMP, coded by gender (black and gray lines denote females and males, respectively). Unconnected points indicate partial data (see Materials and methods section for details). All metabolites were corrected for partial volume effects. Y axes indicate CSF-corrected metabolite levels in institutional units (i.u.). n = 24 participants with 66 scans for analysis (see Materials and methods). Glu glutamate, PBO placebo, MA methamphetamine, AMP d-amphetamine