Further evidence that mice learn a win-shift but not a win-stay contingency under water-escape motivation

Previous research (C. Locurto, C. Emidy, & S. Hannan, 2002) indicated that mice quickly learned a water-escape task under a win-shift contingency but did not exceed chance-level performance under a win-stay contingency. We examined the robustness of this conclusion in two experiments by varying procedural and temporal aspects of that earlier experiment. Results of both experiments indicated that the preference for win-shift learning in mice under water-escape motivation could not be attributed to procedural or design features of that earlier study and were independent of the influence of intertrial interval, normally a variable that produces strong effects on learning. In neither experiment did subjects exposed to a win-stay contingency perform at above-chance levels.