SLC6A3 and depressive symptom measurement: Mixed-effects model analysis of the relationship between striatal DAT SBR and depression symptoms across all timepoints revealed that the effect of MAO-B inhibitor treatment on motivation was moderated by striatal DAT SBR (β=−0.24, 95%CI [−0.43, −0.05], p=0.012) (Table 4, Figure 3).