Some limitations on the use of distal cues in place navigation by rats

Place navigation by rats in the Morris (1981) water task was studied in two experiments. In Experiment 1, rats were trained to escape cool water by locating a goal platform in one half of a pool. Physical and/or visual access to the other half of the pool was restricted through the use of partitions. In subsequent transfer trials involving release from the restricted half, only those rats that had had prior unobstructed swimming and viewing experience in that region snowed accurate transfer. In Experiment 2, viewing access to the room was allowed only during selected portions of the swim (beginning, middle, or after reaching the platform). Rats that were unable to view the room during the middle of the swim showed impaired acquisition. These results imply that rats acquire place information most efficiently while en route to the goal and that place navigation in a familiar environment from starting locations beyond familiar routes and views is inaccurate.