A simple modification of the water maze test to enhance daily detection of spatial memory in rats and mice

The water maze is one of the most frequently used tools in behavioral neuroscience. Many variations of the water maze task have been used; however, established water maze protocols have several disadvantages. Notably, these protocols demand considerable time to perform reference and probe tests separately. Here, we suggest a modified protocol, which is rapidly performed, is sensitive to cognitive deficits, and can assay reference as well as strategy-switching ability. The platform is relocated randomly within the target quadrant with each training trial. Because the rodents must spend more time searching within the target quadrant, every trial effectively becomes a probe trial. The rodents are then run in the switching strategy test, where the platform is randomly placed along the wall of the pool. The best new strategy would thus be to search along the walls of the pool systematically. The percent distance traveled and time spent near the wall is evaluated across trials, as is the distance traveled and time spent in the previously correct quadrant. In this way one can assess whether the rodent is continuing to search in the older platform location (i.e., displaying a strategy-switching problem) or whether it has successfully adopted a new search strategy.