(a, d) AMPA/NMDA ratio as a function of cocaine intake in (a) D2-MSNs and (d) D1-MSNs for sham mice (grey) and all cocaine mice that underwent 17 or more self-administration sessions (red, n=18 mice/green, n=22 mice) . Shaded area represents sham mean ± SD. (b, e) Behavior scores as a function of AMPA/NMDA ratio in (b) D2-MSNs (n = 8 mice) and (e) D1-MSNs (n=15 mice) for mice with high intake and behavioral analysis completed. Color lines are linear regression fit and 95% confidence interval for D2-MSNs and D1-MSNs. (c, f) AMPA/NMDA ratios recorded in the (c) D2-MSNs and (f) D1-MSNs from sham (black, n=15 mice) and cocaine self-administration mice with positive (+) and negative (−) behavior scores (n = 4 and 4 mice for D2-MSNs and n= 8 and 7 mice for D1-MSNs). Dotted line marks the mean AMPA/NMDA ratio in sham animals. Data are mean ± SEM and sample size cells/animals. Refer to suppl. Table 1 for additional sample size information.* p < 0.05, one way ANOVA followed by Bonferroni.