This test is used to assess memory of interactions with novel objects. Rodents tend to spend more time interacting with a new object rather than with an already known object. Acquisition phase: on the first day the animal is habituated to the test chamber. On the second day the animal is placed in the box and allowed to explore two identical objects for a set period of time. Retention phase: on the third day, the animal is returned to the box where one of the familiar objects has been replaced with a novel object. The time exploring the novel object relative to the time spent exploring the familiar object is measured to evaluate memory.