Figure 1.

Delayed nonmatch to sample task based on odors, overview of the training scheme and memory performance on sacrifice day. (A) Top: experimental procedure for the 10-odor group. Ten odors were presented sequentially during the study phase. After 20 min delay, the memory for the 10 “old” studied odors was tested by presenting the “old” odors intermixed with 10 (“new”) odors. The testing odors were presented one at a time. To signal an “old” odor animals should repress digging into the test cup and go to the back of the cage to receive a cereal reward, if correct. To signal a “new” odor, animals should in the test cup to retrieve the same type of rewards. Bottom: experimental procedure for the 5-odor group: only the length of the study and the number of test stimuli changes compared to the 10-odor group. The figure is adapted and modified from Figure 1 in Nakamura et al. (2013). (B) The 5 and 10-odor groups learned to discriminate between “old” and “new” odors within a comparable number of sessions. (C) Memory performance on sacrifice day was also comparable between groups. n.s. not significant. Error bar: SEM.