As previously reported (Delgado et al. 2000; Hariri et al. 2006; Forbes et al. 2009; Nikolova et al. 2012) the card-guessing paradigm reliably elicited reward-related (i.e. positive > negative feedback) bilateral VS reactivity (Fig. 2a). Consistent with our hypotheses, a significant interaction between VS and ELS was associated with anhedonic symptoms when no covariates were included (left VS: ΔR 2 = 0.0057, b = −0.6600, p = 0.0195; right VS: ΔR2 = 0.0046, b = −0.5460, p = 0.0356). Importantly, this interaction remained significant in the left VS even after accounting for sex, age, ethnicity, other depressive symptoms (as measured by the MASQ GDD scale), diagnosis of any psychiatric disorder, and recent life stress (as measured by the number of events reported on the LESS), as well as two-way interactions between these covariates with VS reactivity and CTQ scores (left VS: ΔR 2 = 0.0046, b = −0.7659, F1,789 = 6.52, p = 0.0108; right VS: ΔR2 = 0.0018, b = −0.4146, F1,789 = 2.56, p = 0.1099). Post-hoc analyses revealed that those with relatively reduced left VS reactivity to
