Testing Spatial and Nonspatial Learning Using a Morris Water Maze

INTRODUCTIONAnimal studies of memory have used many different types of mazes and tasks, where the animal is required to learn the demands of the test and then perform correctly until a predetermined performance criterion is reached. Traditional studies have relied on water or food deprivation to motivate the animal to do the test using food or water rewards. In 1984, Richard Morris introduced the water maze. The maze consists of a large cylindrical tank of water with a hidden platform; the animal has to swim until it finds the platform. The animal generally uses cues outside the maze (extramaze cues) to develop a spatial map of the environment and guide its performance. This maze avoids the problems associated with food or water deprivation, because the animal's goal is to find the hidden platform so that it can stop swimming. Many types of memory can be studied by varying the visual cues, the placement of the platform, and the starting point of the animal. This protocol describes the use of the water maze to test rats in two behavioral tasks: a spatial task and a nonspatial, visual task.