FIGURE 1.

(A) Contextual serial discrimination: at the acquisition phase, mice performed two consecutive spatial discriminations varying by the color and texture of the floor, i.e., D1: Discrimination 1 and D2: Discrimination 2. For each discrimination, only one hole out of the four holes of the apparatus was baited (hashed circles). The two discrimination were separated by a 2 min delay interval during which animals are placed in room B. A 24-h delay was interpolated between the acquisition and test phases, during which mice were returned in the colony room. 1 h prior to acquisition and test phases, mice received a per se administration of the compounds or vehicle solution in a chamber placed in a room (room C) different from the one in which the behavioral experiments was conducted (room A). Subsequently, mice were submitted to the test phase in which they were replaced on the floor of the first discrimination without any food pellet in the apparatus. (B) Two types of responses were calculated: (i) correct responses corresponding to head-dips into the hole baited at the acquisition of the first discrimination (D1), on the same floor context; (ii) interference responses corresponding to head-dips into the hole baited at the other (second) discrimination (D2). These two parameters allow calculus of the SCM score.