Here I say that the quote, "O sleep, O gentle sleep, nature's soft nurse, how have I frighted thee?" is from "the Scottish play," a euphemism for *Macbeth*. But in fact it's from *Henry IV, Part 2*.

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.

Russell Foster: Why do we sleep?

Why do we sleep?

Shakespeare to Edison, our views on sleep have evolved, yet modern life undervalues its critical role in health and creativity.

Sleep deprivation linked to obesity, stress, and illness, is a silent crisis, with teens and shift workers among the hardest hit.

Exploring sleep's link to mental health, revealing it as a predictor and potential treatment for mental illness challenges.

What’s the connection between sleep and mental health?

Oxford Online Programme in Sleep Medicine 

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