Intense Sweetness Surpasses Cocaine Reward
The horizontal gray line at 0 indicates the indifference level. Values above 0 indicate a preference for lever S while values below 0 indicate a preference for lever C. *, different from the indifference level (P<0.05, t-test). Each reward type (N, W, Sac and Suc) was tested at least 5 times in a row until stabilization of behavior. Bars represent the means (±SEM) of the last 3 stable days. The first 3 reward conditions (N, W and Sac in this order) were tested in the same group of animals (N = 10) while the sucrose condition was tested in a separate group (N = 10).