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Content Guidelinesplugin-autotooltip__plain plugin-autotooltip_bigContent guidelines

Ideas for new topics are always welcomed, from experts and non-experts alike - if you're not sure if they'll be accepted by other editors, put them in the 'Proposed content' section for approval. The easiest way to create a new page is to use the

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At present, only registered users can create and edit articles. The registration process is very straightforward. Just click the 'Register' link at the top right of any page.

After you've registered, you'll be able to login with your password at any time…

How to edit pagesplugin-autotooltip__plain plugin-autotooltip_bigEditing pages

Once you're logged in, a grey floating 'Tool' menu at the right hand side of the screen enables access to all the main 'Content Pages' for editing. (Note: Some pages, such as the site info etc. are locked)

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Importance Ratingsplugin-autotooltip__plain plugin-autotooltip_bigImportance ratings

In a departure from the usual Wiki format, Wikenigma assigns 'Importance Ratings' to some pages.

The idea is to separate articles which are considered (by the editors) to cover exceptionally important unknown issues from those which (although also u…

Faqplugin-autotooltip__plain plugin-autotooltip_bigFrequently Asked Questions

Q. Why the weird syntax?

A. Like most Wikis, the site doesn't use HTML for formatting (security reasons etc). A guide to the special syntax can be found here. Unfortunately it can be quite confusing at first - but there's now a new 'Visual E…

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• Oct 2020 : A milestone of 500 unknown articles has been reached.

• Aug 2020 : Currently (beta) testing the new 'WYSIWYG' (What You See Is What You Get) page editor. It greatly simplifies the editing process, avoiding the need to learn the…

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Legalplugin-autotooltip__plain plugin-autotooltip_bigLegal

Content in general

Please note that in common with other publicly editable wikis, this website is not responsible for content posted by the public. Nevertheless, the ongoing editing process should be able to remove unsuitable content in a reasonable time. If you…


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The best way to donate is by adding new original content !

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Wikenigma - an Encyclopaedia of Unknowns Wikenigma - an Encyclopaedia of the Unknown Science

Sleep

“The purposes and mechanisms of sleep are only partially clear and are the subject of intense research” Source Wikipedia

Although extensive research in humans and animals has shown unequivocally that sleep is essential, the reasons why it is required are as yet unknown. Long term sleep deprivation not only severely impairs cognitive and motor skills, it's now been shown that it can cause physical damage to brain structure - and, in extreme cases, irreversible damage. [ citation needed ]

From an evolutionary point of view, laying unconscious for extended periods would presumably have made human and animal ancestors vulnerable to attacks, so the necessity of sleep must outweigh the considerable dangers it presents.

There are a large number of theories regarding the function and need for sleep - none has yet been generally accepted as a full explanation.

Hypotheses include:

• Memory consolidation • Waste chemical removal • Energy conservation

To quote William Dement, founder of Stanford University's Sleep Research Center,

“As far as I know, the only reason we need to sleep that is really, really solid is because we get sleepy.” (National Geographic Magazine, May 2010) (paywall)

Unihemispheric sleep

A sleep phenomenon known as 'unihemispheric sleep' - i.e. the ability for just one half of the brain to engage in sleep (while the other half remains fully awake) - has been observed in numerous species, including birds, reptiles and aquatic mammals (e.g. cetaceans, eared seals and manatees).

The reasons why no land mammals (as far as is known) cannot unihemispherically sleep is not known.

“The relative absence of unihemispheric sleep in mammals suggests that a trade off exists between unihemispheric sleep and other adaptive brain functions occurring during sleep or wakefulness. Presumably, the benefits of sleeping unihemispherically only outweigh the costs under extreme circumstances such as sleeping at sea.” source

Note on sleep duration

The American Academy of Sleep Medicine (AASM) and Sleep Research Society (SRS) have developed a consensus recommendation for the amount of sleep needed to promote optimal health in adults, using a modified RAND Appropriateness Method process, and based on more than 4,000 previously published studies. They conclude that :

“Sleeping less than 7 hours per night on a regular basis is associated with adverse health outcomes, including weight gain and obesity, diabetes, hypertension, heart disease and stroke, depression, and increased risk of death. Sleeping less than 7 hours per night is also associated with impaired immune function, increased pain, impaired performance, increased errors, and greater risk of accidents.
Sleeping more than 9 hours per night on a regular basis may be appropriate for young adults, individuals recovering from sleep debt, and individuals with illnesses. For others, it is uncertain whether sleeping more than 9 hours per night is associated with health risk.”

See: Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society

There is currently no explanation as to why some mammals, like humans, appear to need about 8hrs of sleep in each 24hr period - some other mammals routinely sleep 18hrs, and others seem to need only 3hrs or so. [examples needed]


Also see :Sleepwalkingplugin-autotooltip__plain plugin-autotooltip_bigSleepwalking

"“Sleepwalking, also known as somnambulism or noctambulism, is a phenomenon of combined sleep and wakefulness. It is classified as a sleep disorder belonging to the parasomnia family. It occurs during slow wave sleep stage, in a state of low consciousness…
and Dreamingplugin-autotooltip__plain plugin-autotooltip_bigDreaming

"“The content and purpose of dreams are not yet understood, though they have been a topic of speculation and interest throughout recorded history.” source: Wikipedia"

Not only is the function of dreaming unknown (if there is one), but there isn't as yet an…

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