State of reduced or absent consciousness
- The record for the longest period without sleeping is 18 days, 21 hours and 40 minutes.
- Newborn kids spend up to 18 hours of sleep per day, while infants sleep between 14-18 hours in their first year. The rate declines as a child grows.
- Rapid eye movement (REM) sleep accounts for 20-25% of total sleep in human adults.
- Elephants sleep standing up during non-REM sleep, they lie down for REM sleep
- Humans sleep three hours less than chimps, monkeys and baboons who sleep on an average 10 hours.
- Ducks can sleep with one half of the brain awake so that they can protect themselves from attacks by predators
- Some species of sharks such as great whites and hammerheads deactivate one cerebral hemisphere at a time while still moving during sleep.
- Sleep deprivation affects the immune system.
- Fatal familial insomnia, is a genetic disease with no known treatment or cure which results in increasing insomnia until sleep is completely impossible, and eventually results in death.
- Roughly 41 million people in the US, nearly a third of all working adults, get six hours or fewer of sleep a night.
- About 42 percent of workers in the mining industry and about 27 percent of financial or insurance industry workers are sleep-deprived.