Siestas could be better at boosting people's brain power than all nighters. Researchers from the University of California, Berkeley studied 39 healthy young adults. At noon all the participants in the study took part in a rigorous learning task then at 2p.m. half of them had a 90-minute siesta. At six p.m. all the participants did another learning exercise. Those who stayed awake throughout the day became worse at learning while those who took a nap did a lot better and actually improved in their capacity to learn. The researchers found that the memory-improvement process took place in stage 2, non-REM sleep which occurs between deep sleep and REM - the phase of sleep in which we dream.
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