Figure 4.

Results of behavioral analyses for mnemonic similarity tests in Experiment 2. (A) Schematic shows the distinction between a behavioral response to the rat’s inherently biased side, without checking, and to the non-biased side, with checking. (B) Mean (±SEM) percent of correct responses made across four test sessions in which young and aged rats showed checking behavior. Values are shown for each of the three Lure objects (L1, L2, L3). (C) Mean (±SEM) side bias index of young and aged rats across test sessions. A side bias index of 1 reflects complete bias to select the object presented on either the left or right side of the choice platform, while a side bias of 0 reflects no side bias and an equal number of responses made to the left and right sides. (D) Scatter plots show relationships between normalized mean side bias index values and normalized mean percent of correct trials with checking behavior, for Lure 1, Lure 2, and Lure 3 discriminations. Spearman’s rho correlation coefficients and p values are shown for each plot, inset. (E) Mean (±SEM) reaction time values for correct discrimination responses made by young and aged rats on mnemonic similarity tests. Values are collapsed for each trial type but considered separately based on whether rats selected the object presented on their inherently biased or non-biased side.