Interesting • A 2002 study from Oxford University showed that counting sheep, because it is alerting, does not help you get to sleep. • Charles Darwin's grandfather Erasmus believed that spinning around really fast was a great way to induce the slumber • Hippolytus de Marsiliis (born 1451 Bologna) was the first person to document sleep deprivation as a means of torture. • Humans are the only animals where the two adults choose to sleep together for intimacy. • Humans are the only animals who have sex where they sleep. • Humans are the only animals who voluntarily delay or curtail sleep. • Humans have been sleeping on purpose built mattresses, originally made of plant materials, for at least 77,000 years. • In European folklore the Sandman brings good dreams by sprinkling magical sand onto the eyes of children while they sleep. • One of the functions of sleep is to remove neurotoxins that build up in our brains during the day. • Over a lifetime we will spend approx 220,000 hours asleep, more than any other single activity. • Research indicates that sleep probably first arose sometime in the Palaeozoic era around 500 million years ago. • Sleep inertia is that feeling of grogginess some people have in the morning and it can last for up to 2 hours. • Sleep is primarily of the brain and for the brain; only during sleep can the activity of the brain reduce to a significant degree. • Sleep is the only one of our pleasures that we can only enjoy retrospectively. • Sleep talking mostly occurs during deep sleep and so is not normally related to your dreams. • Sleepwalking happens during deep sleep and is not related to dreaming. • The earliest documented sleep theory is attributed to the Greek philosopher and physician Alcmaeon in 500–450 BC. • The Japanese have the concept, inemuri, of it being socially acceptable to sleep in the workplace, even in meetings. • The phrase ‘sleep tight’ has nothing to do with rope beds but simply means to sleep soundly. • The Tudors thought that sleeping flat out was the position of death, so they slept slightly sitting up hence the bolster pillow. • There are over 90 sleep disorders in the current international classification. • There is a rare and potentially dangerous condition, REM Behaviour Disorder, where people are able to act out their dreams. • There is no scientific evidence that cheese has any positive or negative effect on your dreams. The 2005 ‘sleep and cheese’ survey often mentioned in the media was not a scientific study but a PR exercise. • There is no scientific evidence that sleep is affected one way or another by the earth’s magnetic field. • There is no scientific evidence that your sleeping position tells you anything about your personality. • There is no way of getting the ‘benefit’ of 8 hours sleep in 4 hours. • Tudor beds were short not because the people were appreciably shorter but because they did not sleep flat out, the position of death. Animals • Animals sleep when they have met their other biological needs, i.e. water, food and sex. • Dogs can adapt to their owners sleep patterns, cats cannot or will not. • Gorillas are the only primates that like humans sleep on the ground, each night they make a comfortable nest to sleep in. • Hibernation causes significant changes in temperature control and metabolism and is not in any way related to sleep. • When starving some animals can actually forego sleep in order to obtain food. Driving • A quarter of drivers in sleep-related crashes had less than 6 hours of sleep. • Getting just 5 to 6 hours sleep a night increases you risk of having a car accident 3.3 times. • If you fall asleep at the wheel at 60 mph it will take your car only a few seconds to come off the road. • If you feel sleepy when driving opening the window or turning the music up do not work. Pull over and take a break. • Sleep related car accidents are so dangerous because you cannot take any evasive actions; there are no skid marks on the road. • Sleep related car accidents kill more people than drink driving. • The peak times for car accidents are 2-7 am and mid-afternoon when people are most sleepy. • When driving if have problems focusing, blink frequently or have heavy eyelids pull over and have a nap. • When you are driving the first yawn is too late, pull over and have a break Dreaming • Adults wake up preferentially in dreaming sleep, so if you woke up naturally this morning you will probably remember your last dream. • Don’t worry if you dream you are falling and you hit the ground, contrary to popular belief, you will not die. • Everybody dreams 4-5 times a night but you only remember a dream if you wake during it. • If you never remember your dreams you are probably just a good sleeper. • If you remember many dreams during a night it means that your sleep is being disturbed by something or other. • It has been reported that about 70% of the characters in men's dreams are men, while females seem to dream equally of men and women. • Lucid dreaming is where the sleeper becomes aware that they are dreaming and can to a degree control their dreams. • Men generally have more aggressive feelings in their dreams than women, just like when they are awake. • Most dreams in men are associated with having an erection but this has got nothing to do with the content of the dream. • Most people dream in colour but about 10% dream only in black and white. • Most people have a reoccurring ‘stress’ dream, usually based around situations that they would find stressful or make them anxious. • Nightmares are to the dream world what horror films are to the cinema, they are no more meaningful than other dreams. • People suffering from sleep paralysis often report tightness in the chest or not being able to breathe when they wake. • Sleep paralysis, because of the physical sensations, may make your dream seem much more real. • Some dreams may only last a couple of minutes others may be 40 minutes or so. • The most common emotion reported as being experienced during dreaming is anxiety. • When you dream your dreams are real, so if something happens during your dream your mind may think that it really happened. • When you dream your muscles are paralysed so you are unable to act out your dreams. • You can dream about anything you know or can imagine and so the meaning, of your dreams is personal to you. • You can dream that you are flying because it is not something you can do in real life so is not a threat to your awareness of the world. • You rarely dream about smells, conversations or touch as to do so would compromise your vigilance to external threats.