Temperamental traits in mice (I): Factor structure

The present research develops a murine model of the temperamental traits activity, anxiety and novelty seeking. A sample of 140 outbred male mice was assessed in the plus maze (EPM), low frightening open field (LFOF), holeboard (HB) and T maze (TM). An exploratory factor analysis (EFA) was applied to sub-sample 1 (N = 70), and a confirmatory factor analysis (CFA) was applied to sub-sample 2 (N = 70). EFA showed a three-factor solution: activity in LFOF and HB loaded in the first factor; inhibitory behaviours in the EPM loaded in a second factor; and approach behaviour to novel environment in TM loaded in a third factor. CFA analysis confirmed this structure. We have described three replicable factors in mice that could be considered homologous to human personality traits activity, anxiety and novelty seeking.