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By Cathy Evans, Polya Plavinskaia. Subtitle The Science of Snooze. We spend around a third of our lives sleeping. But what actually happens during those hours?. Why Do We Sleep?. Everything you ever wanted to know about sleep but were too exhausted to ask.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.