As shown in Fig. 1a, Ad-shα4-1 infusion into the NAc shell significantly decreased active lever presses 18 days after viral infusion (main effect of day, F(3,44) = 5.4, P < 0.0001; P < 0.05, baseline versus day 18). In contrast, there was no significant change in inactive lever responses (Fig. 1b; F(3,44) = 2.17, P = 0.88; range: 0–6 per 30 minutes session). We also observed a reduction in ethanol intake in grams per kilogram, calculated from the number of reinforcers delivered relative to the body weight of the subjects (Fig. 1c; main effect of day, F(3,44) = 4.6, P < 0.0001; P < 0.05, baseline versus day 18) in accordance with the decrease in active lever-press responding.
