Fig. 2

The onset of memory impairments in APP/PSEN1-Tg occurs at 3 months old. Novel object recognition (NOR) test: grey (non-transgenic) and yellow (APP/PSEN1-Tg) bars represent the novel object 1 and 2 discrimination index (%) at 3 (a) (non-transgenic n = 15, APP/PSEN1-Tg n = 16) and 6 months old (d) (non-transgenic n = 12, APP/PSEN1-Tg n = 14). Data are presented as mean ± SEM. *p < 0.05, **p < 0.01 (two-way ANOVA). T-maze left–right discrimination learning: b, e solid (non-transgenic) and dotted lines (APP/PSEN1-Tg) represent the escape latencies of both groups at two different ages (ANOVA of repeated measurements *p < 0.05; ⁺p < 0.05 comparison of APP/PSEN1-Tg vs the 1st trial; *p < 0.05 comparison of APP/PSEN1-Tg vs non-transgenic). c, f Grey (non-transgenic) and yellow (APP/PSEN1-Tg) bars represent the mean ± SEM trials to criterion during acquisition and reversal phase latencies at 3 (n = 16 per group) and 6 months old (non-transgenic, n = 12, APP/PSEN1-Tg n = 14). f At 6 months old, transgenic mice tend to reach the criterion later than control groups during acquisition (Student’s t-test, non-transgenic vs APP/PSEN1-Tg, *p < 0.05; ^#p = 0.068)