Fig.1.

NOD test series layout. The test consisted of 5 min object acquisition, 6 h latency, 5 min object recognition, 18 h latency, and 5 min object location. Note that the empty circles represent two identical copies of the same “old” object that becomes the familiar object in Choice 1 when a new (“novel”) object (black circles) is introduced in the arena. The “novel object” switched positions with the “old object” to regain novelty in the new location.