Supplementary Figure 1.

Protocol of the conditioned place preference (CPP, A) and the bottle choice (BC, B) test. The animals were tested for the most preferred chamber or cage side at day 0. During the conditioning the less preferred chamber/cage side was associated with rewarding stimuli (sucrose pellets or 0.8 M sucrose solution), alternating with non-rewarding stimuli in the preferred chamber/cage side. On the test day mice had to choose between empty chambers or 2 bottles filled with water.