A comparison of rats and mice in a swimming pool place task and matching to place task: some surprising differences.

An ecological niche that requires competency in water has prepared rats for the swimming pool spatial tasks that they are administered in the laboratory. Their ability to eventually solve spatial tasks in a single trial makes them ideal subjects for evaluating neural contributions to spatial behavior and for addressing many other neuroscience problems. Swimming pool place tasks are also given to mice, but the spatial abilities of the animal has not been evaluated as extensively as have those of rats. In the present paper, place learning in a single place task and a matching to place task is comparatively assessed in groups of rats and mice. The rats were superior to the mice on both problems. Although the mice could learn a single place problem, their acquisition was slower and their asymptotic performance was inferior to that of rats. Mice also did not display one trial learning on the matching to place task as did rats. These species differences in swimming pool place learning are discussed with respect to both methodological considerations and to species differences in preparedness to learn. It is suggested that given the variability of the performance of mice across both strains and laboratories, rat performance could be used to provide a baseline for comparative purposes.