Study co-author Jessica D. Payne of the University of Notre Dame says research indicates sleep helps in reorganizing memories, picking out emotional details and may even help in taking memories apart to create new ideas.
The study, published in Psychological Science, suggests emotional objects are used to fix memories.
Payne and Elizabeth Kensinger of Boston College tested participants before and after sleep, as well as measured brain activity while the subjects slept.
"Sleep is making memories stronger. It also seems to be doing something which I think is so much more interesting, and that is reorganizing and restructuring memories," Payne said in a statement.
"The brain is busy. It's not just consolidating memories, it's organizing them and picking out the most salient information. We can get away with less sleep, but it has a profound effect on our cognitive abilities."
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