Figure 5.35: A genetically altered “smart” mouse being tested for object recognition Mice, like other mammals, explore new objects more than familiar ones. In this test, each mouse was exposed to two objects: one that it had explored in a previous 5-minute session and one that was new. Mice that were genetically altered to produce enhanced LTP explored the new object (in this case, the one on the right) more than the old one even when several days had elapsed since the initial session. In contrast, unaltered mice explored the new object more than the old one only when a shorter period of time had elapsed. These results indicate that the altered mice remembered the original object for a longer period of time than did the unaltered mice.
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