Differential Effects of Scopolamine on Memory Processes in the Object Recognition Test and the Morris Water Maze Test in Mice

Abstract

Abstract −Several lines of evidence indicate that scopolamine as a nonselective muscarinic antagonist dis-rupts object recognition performance and spatial working memory when administered systemically. In thepresent study, we investigated the different effects of scopolamine on acquisition, consolidation, and retrievalphases of object recognition performance and spatial working memory using the object recognition and theMorris water maze tasks in mice. In the acquisition phase test, scopolamine decreased recognition index onobject recognition task and the trial 1 to trial 2 differences on Morris water maze task. In the consolidation andretrieval phase tests, scopolamine also decreased recognition index on object recognition task, where as sco-polamine did not exhibited any effects on the Morris water maze task. Keywords : Scopolamine, Object recognition test, Morris water maze, Acquisition, Consolidation, Retrieval INTRODUCTION There are three stages for learning and memory pro-cessing including acquisition, consolidation, and retrievalprocesses (Abel and Lattal, 2001). After detection by thesensory system, information is rapidly encoded and maypass into labile memory. During consolidation, this mem-ory may then be consolidated into long-term storage. Theretrieval process is the final stage which uses the consoli-dated and more fixed memory. It is important to know theeffects of a compound on each stage of memory pro-cessing as the compound which improves multiple cogni-tive processes will be most useful as a treatment formemory deficits (Prickaerts