Para quem dorme muito...

(Eu por acaso nem sou de dormir muito...)

A ler os diferentes artigos na Nature sobre o assunto.
The fundamental truths of sleep are not difficult to master: one sleeps when one is tired — mostly at night—and awakens the next day usually feeling rested and refreshed.

So why put together an Insight on a topic that seems so straightforward?

Although it is often true in biology that things are more complex than they seem at first glance, it is especially accurate for sleep. This became apparent about 50 years ago with the discovery of rapid eye movement (REM) sleep. This is a sleep state marked by intense brain activity, rapid bursts of eye movement and vivid dreaming. The high level of brain activity during REM sleep created a serious challenge to the prevailing dogma — that we sleep simply to provide rest — and raised a host of largely unanswered questions about the function of sleep.