An extract from Why We Sleep by Matthew Walker

Suppose you have a new baby, and your obstetrician is telling you about the neonatal exam. He says that you have a beautiful healthy baby boy, but there are a few things you should be aware of, as new parents.

“Frequently your baby is going to go unconscious… and be unresponsive to normal stimulation. The frequency of these … unconscious attacks … will gradually decrease to one a day by the time he goes to school, but they will last throughout life. Periodically throughout unconsciousness, he will be paralysed except for some jerks and twitches, his eyes will dart back and forth and his heart and breathing rate will get irregular. As he gets older he will get hallucinations during these episodes. he will hear voices and see things that aren’t there. Some of these things will be very strange, and maybe even terrifying, causing him to sit up and utter screams of fright - but not a problem, because this condition is also characterised by total amnesia. The chances are that he wont remember most of these terrifying episodes.”

So you as a parent might think what? Amnesia… attacks of unconsciousness… paralysis… jerks and twitches…. hallucinations? Eyes darting back and forth?

To which the obstetrician says “Oh not to worry. Its just this thing, and its called sleep.”

We spend a third of our lives in this state. Yet, modern medicine still cannot definitively tell us why.

- Matthew Walker, Why We Sleep (2017).