Fig. 2

Performance in Morris water maze acquisition across age. To assess how fast TG and WT rats learned a new platform location in the MWM task, the average latency to find the platform in the first eight learning trials was calculated at each age time point (a). TG rats were significantly slower in finding the platform than WT rats across time points. To assess working memory performance, the latency to find the platform in trials 2–4, which were 30 s apart, was compared between genotypes (b). TG rats demonstrated worse performance in working memory than WT rats. Comparing performance in trial 5 was used as a measure of memory as all rats had completed four learning trials 50 min prior (c). A significant effect of genotype was observed in trial 5, and TG rats performed significantly worse at 16 months of age. 24-h memory performance in trial 9 was not significantly different between genotypes (d). Swim pattern analysis showed that TG rats exhibited the “direct immediate” swim pattern (DIM), a sign of accurate memory, significantly less often than WT rats in trials 2–5 (e). Graphs show mean ± SEM. One asterisk indicates p < 0.05, three asterisks indicate p < 0.001 (two-way ANOVA results indicated beside genotype and results of Sidak’s multiple comparisons indicated on bars)