Figure 1. Experimental protocol.

(A) Typical protocol for experiment 1. Rats foraged for chocolate sprinkles in a rectangular box (1.2m × 1.5 m) for 15 minutes in 6 consecutive sessions. The first session of the first day did not have any objects. Four objects were introduced in session 2; these 4 objects and their locations became the standard configuration for the rest of the experiment for the given rat. Sessions 2–6 on day 1 and all sessions on days 2 and 3 had objects in the standard configuration. Object manipulations were performed in sessions 3 and 5 on days 4 and 5. Session 3 here shows the introduction of a novel object and session 5 shows the misplacement of one object; the type of object manipulations was counterbalanced between sessions 3 and 5 on days 4 and 5. (B) Protocol for experiment 2. Rats foraged for chocolate sprinkles in a square box (0.8m × 0.8 m). There were no objects in session 1, and the same object was placed at 3 different locations in sessions 2 through 4. (C) Representative objects used in the experiments. (A) and (C) are reproduced from Deshmukh and Knierim (2011).