Fig. 8.

Performance of PLB1_WT and PLB1_Triple mice in two object recognition tasks. a Overall locomotor activity during habituation session H1 and H2: Activity was lower in H2 than H1 for all cohorts except PLB1_Triple mice aged 12 months. b Ambulatory velocity was different between H1 and H2 at all age groups, but not related to factor phenotype. c Novel object recognition—sample phase: independent of genotype, animals spent equal amounts of time with objects A and A*. Note the age-related reduction in object exploration to about 50 % in 12 month old subjects. This was independent of genotype. d Novel object recognition—test phase: Object A* was replaced by object B. Discrimination index confirms that while PLB1_WT mice prefer object B (positive index), PLB1_Triple mice clearly did not (asterisks)—there was a small bias for the familiar object. e Object recognition, spatial shift sample phase: exploration was equal for objects C and D independent of age and genotype. f Object recognition, spatial shift test phase: Object D was shifted to a novel location. Discrimination index confirms that while PLB1_WT mice prefer object D (positive index), PLB1_Triple mice clearly did not (asterisk). The positive index of PLB1_Triple mice at 12 months of age was due to two subjects. Note that index is not different from chance (0). All data are presented as mean ± SEM. *p < 0.05; **p < 0.01; ***p < 0.001 between genotype (t test). ^$ p < 0.05, ^$$ p < 0.01, ^$$$ p < 0.001 relative to chance. Tracks of representative animals aged 4 months undertaking object novelty test (top) and spatial shift (bottom) are also indicated. Circles indicate in-object zones, in which tracking was recorded as exploration. B novel object, D shifted object