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TEDTalks | Russell Foster: Why do we sleep?

submitted by Procrastinatron
1 decade 1 year 3 months 1 week ago

(Description via YouTube)

Russell Foster is a circadian neuroscientist: He studies the sleep cycles of the brain. And he asks: What do we know about sleep? Not a lot, it turns out, for something we do with one-third of our lives. In this talk, Foster shares three popular theories about why we sleep, busts some myths about how much sleep we need at different ages -- and hints at some bold new uses of sleep as a predictor of mental health.