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.