Extending possible applications of an episodic-like memory task in rats

Recently, an object recognition episodic-like memory task was proposed in rodents. However, the short retention delay of the task narrows its applications. This study verifies whether this task can be evoked after 24 h. Additionally, the effect of a classical amnestic agent (scopolamine) on episodic-like memory consolidation was investigated. Rats showed increased exploration of old over recent objects and spent more time exploring displaced over stationary object. Both old over recent and displaced over stationary objects preferences were abolished by pos-training scopolamine administration (1 mg/kg i.p.), indicating impaired spatiotemporal retrieval. In conclusion, the object recognition task that accomplishes the what, where and when components of episodic-like memory in rats can persist for 24 h.