Recollection of What-where-which Memory in Degus (octodon Degus)

To examine if a feature of episodic-like memory reported in rats is shared with other species, we investigated whether degus would form an integrated memory of object (what), place (where), and context (which). We used two E-shaped mazes with different contexts regarding the wall and the floor. Degus were entered into the middle arm and first explored the maze with two trial-unique objects placed at each end of the backbone of the E, with their location reversed between contexts. After being habituated to one of the objects in the holding cage, the degus re-explored the maze. Subjects explored the non-habituated object in these baseline trials. In the critical test, the objects were located at the end of the outer arms of the maze. Degus went into the arm where they expected the non-habituated object significantly more often than the other. This result suggests recollection of an integrated What-WhereWhich memory.