With the exception of male C57BL/6J (E) and female CAST/EiJ mice (S), male (A, I, M, Q) and female mice (C, G, K, O) from all strains in the paired group developed the goal-tracking response as indicated by a significantly greater goal-tracking rate during trials relative to inter-trial intervals. In contrast, GT rate during trials and inter-trial intervals did not differ in the unpaired group in male (B, F, J, N, R) or female (D, H, L, P, T) mice of any strain. Goal-tracking rate was quantified using infrared beam breaks.
* p < .05