Unlearned anxiety predicts learned fear: a comparison among heterogeneous rats and the Roman rat strains. - López-Aumatell, R; Vicens-Costa, E; Guitart-Masip, M; Martínez-Membrives, E; Valdar, W; Johannesson, M; Cañete, T; Blázquez, G; Driscoll, P; Flint, J; Tobeña, A; Fernández-Teruel, A (Behavioural brain research, 2009)