Research Paper Volume 15, Issue 13 pp 6031—6072

Figure 2. Enrichment reduces novelty-induced locomotion in adult mice. An RM-ANOVA on the open field task in the Adult groups showed an effect of Time for all groups (F(5,300) = 49.74, p < 0.0001) indicating a reduction in activity over time, and also a Housing effect (F(1,60) = 9.88, p = 0.003) showing that mice in the enriched groups were less active regardless of their genotype. Following the introduction of an object into the arena (broken vertical line; 50 ml plastic Falcon tube), exploration increased from the previous level of activity at 60 mins. There was a borderline genotype effect (F(1,60) = 4.02, p = 0.049) with the WT group showing an enhanced response to novelty. Subsequently, enrichment reduced exploration in both genotypes following the introduction of an object, with a significant interaction of Time x Genotype x Housing (F(5,300) = 51.75 p = 0.012). In this open field + object stage an RM-ANOVA also showed an effect of Time for all groups (F(5,300) = 128.53, p < 0.0001) indicating a reduction in activity over time, and also a Housing effect (F(1,60) = 17.03, p < 0.0001) showing again that enriched mice were less active in response to the introduction of an object regardless of their genotype. The data are presented as distance travelled in metres as cumulative distance reported in 10-min intervals. 60 min per stage (120 min in total). Datapoints are presented as mean ± SEM. The heatmaps below the graphs depict the arena occupancy in the open field ± object stages for the mice of each group.