Sleep is essential for many aspects of normal life, but how we actually fall asleep remains a mystery.

Finding the tipping point for sleep.jpg

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Researchers have now shown how specialist nerve cells in the brains of fruit flies trigger several key steps of falling asleep.

The team at Oxford University’s Centre for Neural Circuits and Behaviour worked with a small cluster of neurons that had previously been shown to put flies to sleep when activated. When the flies are awake the sleep-control neurons are turned off. The longer the flies are awake, the more tired they become, which eventually reaches a tipping point and activates the neurons.

But the fact that the sleep-inducing neurons are only a tiny minority of all nerve cells posed a puzzle. Sleep entails some of the most profound and widespread changes our brains experience on a daily basis. How could so few cells control so much?

Find out more (University of Oxford website)