Figure 4. Effect of prior experience on performance of Tg PDAPP, Tg PDAPP(D664A) and non-Tg littermates in the MWM.
aLeft panel, performance of all experimental groups was significantly improved with increasing age and experience [significant effect of age at testing on performance, F(2,79)=6.57, P=0.002, repeated measures two-way ANOVA]. Tg PDAPP mice were significantly impaired with respect to non-Tg controls (P<0.001) and with respect to Tg PDAPP(D664A) mice [P<0.05, as a result of Bonferroni’s post test applied to a significant effect of genotype, F(2,2)=23.76; ***P<0.0001, repeated measures two-way ANOVA]. Right panel, mean latencies for all genotypes. b. Performance at first and last swim during training at 7, 9 and 13 mo. Latencies to find the escape platform were reduced at last swim with respect to the first swim of each training period for non-Tg and Tg PDAPP(D664A), but not for Tg PDAPP mice except at 9 mo, when performance of Tg PDAPP mice also improved as a result of training. *, significant effect of genotype on performance, F(2,5)=2.45, P=0.0003, two-way ANOVA. Retention was observed between 7 and 9 mo, but not between 9 and 13 mo for non-Tg and Tg PDAPP(D664A) groups. Data are means ± SEM