task became popular is that rats (but not mice) are natural swimmers, but dislike colder water (mice simply dislike water of any temperature), so in order to perform the task they do not need to be motivated by food deprivation or electrical shock. The mobility of the platform allows for experiments on learning and relearning. Also, the apparatus set-up and costs are relatively low. Weaknesses When the searching times for the platform in the target quadrant are reduced in the probe trial, this is seen as direct evidence that the spatial memory of the mouse must be impaired. However, many times the reason for a lengthier amount of time spent looking for the platform, or the lack of searching in the target quadrant, has nothing to do with an effect on the mouse's spatial memory, but is actually due to other factors. A large study of performance in mice concluded that almost half of all variance in performance scores was due to differences in thigmotaxis, the tendency of animals to stay close to the walls of the pool. About 20% of the variability was explained by differing tendencies of mice to float passively in the water until "rescued" by the experimenter. Differences in spatial memory were only the third factor, explaining just 13% of the variation between animals' performance. See also Oasis maze Barnes maze Elevated plus maze References Animal testing mazes Behavioral neuroscience