Buzz
Sleep science is a relatively recent field, with the majority of current understanding being gained in just the past 25 years. Here’s a collection of 20 fascinating facts about sleep.
Facts 1 – 10
1. The longest known duration without sleep is 18 days, 21 hours, and 40 minutes during a rocking chair marathon. The person who set this record experienced hallucinations, paranoia, blurred vision, slurred speech, and lapses in memory and concentration.
2. It’s nearly impossible to determine if someone is truly awake without close medical monitoring. People can take brief naps with their eyes open without even realizing it.
3. If it takes you less than five minutes to fall asleep at night, it indicates you’re sleep deprived. The ideal time is between 10 and 15 minutes, which means you're still tired enough to fall into deep sleep, but not so drained that you’re exhausted during the day.
4. Dreams, once thought to occur only during REM (Rapid Eye Movement) sleep, also take place (though to a lesser extent) during non-REM sleep stages. It’s possible that no moment of our sleep is entirely dreamless.
5. REM sleep dreams are often strange and unpredictable, while non-REM dreams are repetitive and thought-like, with minimal imagery – like constantly worrying that you left your mobile phone somewhere, for instance.
6. Certain eye movements during REM sleep are linked to specific movements in dreams, suggesting that part of the dreaming process is akin to watching a movie.
7. Elephants stand while sleeping during non-REM sleep, but they lie down when they enter REM sleep.
8. Some researchers believe we dream to solidify experiences in long-term memory, meaning we dream about things that are worth remembering. Others propose we dream to forget – to clear out unnecessary memories that would otherwise crowd our minds.
9. Dreams may have no particular purpose and might simply be a meaningless result of two evolutionary adaptations – sleep and consciousness.
10. A 1998 study remains unexplained, showing that shining bright light on the backs of human knees can reset the brain’s sleep-wake cycle.
Facts 11 – 2011. Researchers from the British Ministry of Defence have successfully adjusted soldiers' body clocks, allowing them to stay awake for up to 36 hours. Special spectacles containing tiny optical fibers emit a ring of bright white light (mimicking the spectrum of a sunrise) around the soldiers' retinas, tricking them into believing they’ve just woken up. This system was first used on US pilots during the Kosovo bombing.
12. The 1989 Exxon Valdez oil spill in Alaska, the Challenger space shuttle disaster, and the Chernobyl nuclear accident were all linked to human errors, with sleep deprivation being a contributing factor in each case.
13. Some people possess a “natural alarm clock” that allows them to wake up roughly when they wish. This is triggered by a surge of the stress hormone adrenocorticotropin, which is believed to be the body’s unconscious response to the impending stress of waking up.
14. Even small beams of light from a digital alarm clock can disrupt your sleep cycle, even if you don’t fully wake. The light deactivates a “neural switch” in the brain, causing a rapid drop in the levels of a vital sleep chemical.
15. Humans typically sleep about three hours less than other primates such as chimpanzees, rhesus monkeys, squirrel monkeys, and baboons, all of which sleep for about 10 hours a night.
16. Ducks, facing the threat of predators, manage to balance sleep and safety by keeping one half of their brain alert while the other rests.
17. Historical diaries from the Victorian era, before the advent of electric lighting, reveal that adults would sleep for nine to 10 hours per night, with their sleep patterns shifting in accordance with the changing seasons and the rising and setting of the sun.
18. The majority of our understanding of sleep has been acquired within the last 25 years.
19. The additional hour of sleep gained when clocks are set back at the beginning of daylight saving time in Canada has been linked to a reduction in the number of road accidents.
20. Experts argue that one of the most tempting distractions from sleep is the constant availability of the internet, accessible around the clock.
Source: ABC News Australia
