When taken before creating new memories. However, a recent study revealed that taking a pill of caffeine after learning to do something really has an impact to improve the evocation of memories until 24 hours later. Participants memorized geniux a series of images and then were examined to show the same images (goals), similar images (decoys), and completely different images. The task was to select the exact images they had memorized without being fooled by decoys (which were very similar.) This process is called pattern separation, which the researchers reflects a "deeper level retaining memories."

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