Can people live without sleep

How long can you stay awake?

The officially valid answer is provided by a well-documented experiment: It is 264 hours, i.e. around 11 days. This unofficial world record was set by the 17-year-old student Randy Gardner on the occasion of a science event in 1965.

In the same year, however, the first contenders emerged claiming to have broken the record again - a pattern that continues today. The newest candidate to be taken seriously is an Englishman who filmed himself staying awake for 266 hours. However, the highest authority in such record disputes, the Guinness Book of Records, is no longer of any help in this case: for some years now, it has refrained from setting sleep deprivation records due to possible health risks. Gardner will probably stay the record holder forever - at least officially.

The consequences of not getting enough sleep

What is certain, however, is that Gardner was not an absolute exception and that some others lasted at least as long. For example, some volunteers were awake for eight to ten days under careful observation as part of scientific experiments. None of these candidates subsequently reported any serious medical, neurological, sensory or psychological problems. However, as the experiment progressed, all of them had increasingly clear deficits: They reported weaknesses in concentration and perception as well as indifference and revealed problems in various other mental processes. All of this reappeared in all test subjects after one or two nights of restful sleep.

The facts are anecdotally supplemented by stories from soldiers who stayed awake for four days during combat; or from patients with manic disorders who have not slept for three to four days without medication. In fact, medical professionals have long been making use of the positive effects of sleep deprivation: In what is known as waking therapy, therapists prescribe a sleepless night for patients with depression, which temporarily lifts the mood of many affected people.

More difficult than answering the question of who is awake time record holder is to define what exactly "awake" actually means, says chronobiologist J. Christian Gillin of the University of California at San Diego, who researches sleep and mood disorders. After all, prolonged sleep deprivation induces, in addition to all sorts of altered states of consciousness, frequent "microsleep" in healthy subjects - short episodes in which sleep overwhelms one - as well as partial or complete loss of cognitive or motor control over what is happening. This is exactly what makes overtired car drivers dangerous or pilots who fall asleep and crash their aircraft, which probably happened not infrequently after missions in the Second World War, for example. Record holder Randy Gardner also stayed "awake" for days, but gradually revealed increasingly clear signs of failure: first he could no longer see objects clearly, then he showed memory gaps and mood swings. At the end of his ordeal, he was barely able to act.

And the long-term consequences? There have been experiments on rats to prove that continuous sleep deprivation can be fatal. Allan Rechtschaffen from the University of Chicago had therefore constantly woken animals that had to balance on a rotating disk above a pool of water at the risk of falling as soon as they fell asleep - which was continuously monitored using their brain waves. The cause of death of the animals could not be definitively determined in the end, but they probably died of complete exhaustion and metabolic overload. It is questionable whether the stress of the experiment did not have a major influence here.