Different activity parameters recorded during the dark and light cycles in home cage over 12 days, including baseline distance moved in each hour (A), distance moved in each hour after introducing running wheel (B), baseline velocity of movement (C), and velocity in running wheel (D), are presented. Both distance moved and velocity, during baseline and after introducing the running wheel, were higher in Ts65Dn mice than 2N mice (main effect of genotype). Mean + SEM is shown and n=8 for all groups. Within group comparison between each pair of genotypes was analyzed and only the significant differences are shown (*=p<0.05 and **=p<0.01).