Mysteries of Sleep: 45 Fascinating Facts About the Brain and Body at Rest 2

26Falling Asleep

Falling Asleep

It only takes 10-20 minutes for an average person to fall asleep.

27. Exploding head syndrome is an event in which a person hallucinates a short and extremely loud noise as they are falling asleep. Despite the name, the syndrome isn’t associated with any dangerous condition.

28. The United States Navy Pre-Flight School created a routine to help pilots fall asleep in 2 minutes or less. It took pilots about 6 weeks of practice, but it worked even after drinking coffee and with gunfire noises in the background.

29. Drockling is the act of repeatedly falling asleep and waking up in the morning while hitting the snooze button. Drockling can make you feel drowsier in the morning despite getting more sleep.

30. Manipulating your core body temperature through hot baths, showers, or saunas can have dramatic effects on your ability to fall asleep and stay asleep.



Sexsomnia is a sleep disorder where people experience sleep-related sexual behavior. These behaviors range from masturbation to sexual intercourse. People with this disorder engage in sexual behaviors while asleep, often with other people.

32. Falling asleep during summer or in hot environments is harder because our body temperature lowers 1 to 2 degrees when we sleep. An optimal room temperature for falling asleep is around 18.3°C or 65°F.

33. The human womb is the oxygen equivalent of the top of Mount Everest which is designed to keep the fetus asleep 95% of the time.

34. In 2015, a basketball player named Shanice Clark was found dead in her bed. The cause of her death was ruled to be falling asleep with gum in her mouth and breathing it into her lungs.

35. In one survey, 56% of the pilots have admitted sleeping on the job while 29% of the pilots have woken up to find the other pilot asleep as well.

36Hypnic Jerk

Hypnic Jerk

The sensation of feeling like you are falling when you are drifting into sleep is called a hypnic jerk. There is no definitive reason why it happens. One theory is that the rapid decrease of heart rate and relaxation tricks your brain into thinking you are about to die so you get a jolt of adrenaline to wake you up.

37. During World War 1, a Hungarian man named Paul Kern was shot in the frontal lobe making it impossible for him to fall asleep. He continued to live a full, sleepless life.

38. It is nearly impossible to read in your dreams due to the inactivity of those parts of the brain while asleep.

39. The Tetris effect (also known as Tetris Syndrome) occurs when people devote so much time and attention to an activity that it begins to pattern their thoughts, mental images, and dreams. It takes its name from the video game Tetris.

40. When dreaming, hardcore video gamers have been reported to be able to toggle between first and third-person point-of-view; readily take control over and even enjoy nightmares; and have more dreams that involve far-fetched or impossible scenarios, like imaginary characters or space travel.

41Communication While Dreaming

Communication While Dreaming

It’s possible to have complex communications with someone who is dreaming. Researchers of one study found two-way communication during REM sleep is possible when study participants (having confirmed lucid dreams) answered questions correctly via eye movement. They were even able to solve simple math equations.

42. People who grew up with black and white TV dreamed in black and white about a quarter of the time. People who were under 25 at that time only dreamt in black and white about 4.4% of the time.

43. Dreams are thought to strip memories of emotion. According to the theory, this function fails in sufferers of PTSD. Recurring nightmares might therefore be a repeated attempt at performing this function.

44. A study suggests melatonin, the hormone associated with control of our sleep-wake cycles, evolved 700 million years ago from our tiny oceangoing ancestors that would swim to the surface of the sea at twilight and then sink into the depths of the ocean in a sleepy fall through the night.

45. Wes Craven found inspiration for "Nightmare on Elm St" from the story of young male refugees who mysteriously died in their sleep. One child claimed to be afraid to sleep because he would be attacked in his dreams. When the child eventually fell asleep, he died. The cause behind this phenomenon is still unknown.